Subido por Jaime L.

CadnaA Reference 2018

Anuncio
Reference Manual
The specifications and data given in this documentation are subject to modification without prior notice.
Unless otherwise stated, any names and data used in the examples are completely fictitious.
No part of this documentation may be reproduced or transmitted for whatever purpose, in any form or by
any means (electronically or mechanically), without the express permission in writing from DataKustik
GmbH.
 DataKustik GmbH. All rights reserved.
Gilching, October 2017 (release 2018, 161.4800)
CadnaA is a registered trademark of Datakustik GmbH, Gilching, Germany.
Contents III
Contents
License Agreement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .XV
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . XIX
Chapter 1 - Introduction
Structure of CadnaA documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3
New Features of CadnaA 2018 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7
Notations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11
Literature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13
Chapter 2 - Sound Sources
Industrial Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-3
Common Input Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7
ISO 9613 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-27
Nordic Prediction Method 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . 2-29
Nord 2000. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-31
Ljud från vindkraftverk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-33
BS 5228 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-35
Harmonoise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
Concawe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-39
NMPB-Industry 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-41
CNOSSOS-EU (Industry) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-43
Schall03 (2014) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-45
HJ 2.4 (2009) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-47
Further Procedures for Industrial Noise . . . . . . . . . . . . . . . . . . . . 2-49
Directivity at Industrial Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-51
Sound Radiation from Chimneys or Stacks . . . . . . . . . . . . . . . . . 2-57
Sound Radiation from Elements & Openings . . . . . . . . . . . . . . . . 2-59
Frequency-dependent Directivity . . . . . . . . . . . . . . . . . . . . . . . . . 2-63
Tennis - Point-of-Serve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-67
Roads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-73
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Common Input Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-75
RLS-90 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-89
Nordic Prediction Method 1996 . . . . . . . . . . . . . . . . . . . . . . . . . 2-103
NMPB-Routes 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-111
NMPB-Routes 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-119
CNOSSOS-EU (Road) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-127
CRTN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-137
TNM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-145
Czech Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-151
SonRoad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-157
HJ 2.4 (2009) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-161
Further Procedures for Road Noise . . . . . . . . . . . . . . . . . . . . . . 2-167
Air Pollution according to MLus-92. . . . . . . . . . . . . . . . . . . . . . . 2-169
Crossings with Traffic Lights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-171
Railways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-179
Common Input Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-181
Schall 03 (1990) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-189
Schall 03 (2014) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-195
Nordic Prediction Method 1996 . . . . . . . . . . . . . . . . . . . . . . . . . 2-205
CRN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-211
SRM II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-217
NMPB-Fer 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-225
NMPB-Fer 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-229
CNOSSOS-EU (Railway) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-233
FTA / FRA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-243
Further Procedures for Railway Noise . . . . . . . . . . . . . . . . . . . . 2-253
Train Class Libraries . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-255
Traffic-Count Calculator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-269
Parking Lots. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-271
RLS-90 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-275
LfU-Study (2007) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-277
SN 640 578 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-285
Pass-By of individual Vehicles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-289
Optimisable Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-299
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Chapter 3 - Obstacles
Building . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3
Residential and non-residential Buildings . . . . . . . . . . . . . . . . . . . 3-9
Acoustic Transparency (%) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11
Snap Point to Facade . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17
Edit Facades . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21
Defining a Roof Ridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33
Generate Building. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-39
Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-41
Floating Barrier . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-43
Barrier with special crowning . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-47
Barrier with transmission . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-53
Barrier staggered in height . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-59
Bridge . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-61
Ground Absorption Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-63
Built-Up Areas and Foliage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-65
Cylinder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-69
3D-Reflector . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-71
Embankment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-87
Automatically Optimize Noise Barriers . . . . . . . . . . . . . . . . . . . . . 3-91
Chapter 4 - Topography
Terrain generating Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-9
Contour Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-11
Height Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15
Line of Fault . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-19
Object’s Geometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-21
Point-like Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-21
Line-like Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-25
Area-like Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-29
Additional Input Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-31
Topography-specific Functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-37
Fit Objects to DTM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-39
Fit DTM to Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-45
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Generate Terrain Contours from Height Points . . . . . . . . . . . . . . 4-51
Generate a Grid of Height Points from
Terrain Contours . . . . 4-57
Generate Cluster of Heights Points from Bitmap . . . . . . . . . . . . 4-63
Chapter 5 - Immissions
Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Consistency Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-9
Partial Levels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-11
Area of Designated Land Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-13
Type of Land Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-15
Receiver Grid. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-17
Grid Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-25
Grid Appearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-31
Grid Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-39
Grid Arithmetic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-41
Generating a Grid from Noise Contours . . . . . . . . . . . . . . . . . . . . 5-51
Vertical Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-57
Building Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-61
Building Noise Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-69
Result Table for the Building Noise . . . . . . . . . . . . . . . . . . . . . . . 5-79
Level Difference Map for Building Noise . . . . . . . . . . . . . . . . . . . 5-83
Chapter 6 - Calculation
Sound Rays and Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-3
Sound Rays at Point Sources . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
Sound Rays at Line and Area Sources . . . . . . . . . . . . . . . . . . . . . 6-7
Projection at extended Sound Sources . . . . . . . . . . . . . . . . . . . . . 6-9
Reflection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-13
Reflection of the 1st Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-15
Reflections of Higher Order . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-19
Displaying Sound Rays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-23
Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-31
Country Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-33
General Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-35
Partition Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-51
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Reference Time Tab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-59
Evaluation Parameters Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-65
DTM Digital Terrain Model Tab . . . . . . . . . . . . . . . . . . . . . . . . . . 6-71
Ground Absorption Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-75
Reflection Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-77
Industry Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-87
ISO 9613 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-93
Nordic Prediction Method (1996) . . . . . . . . . . . . . . . . . . 6-111
Nord 2000 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-117
Ljud från vindkraftverk . . . . . . . . . . . . . . . . . . . . . . . . . . 6-123
BS 5228 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-127
Harmonoise . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-133
Concawe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-141
NMPB-Industry 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-151
CNOSSOS-EU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-155
HJ 2.4 (2009) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-157
Road Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-159
RLS-90 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-165
Nordic Prediction Method (1996) . . . . . . . . . . . . . . . . . . 6-171
NMPB-Routes 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-179
NMPB-Routes 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-185
CNOSSOS-EU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-189
CRTN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-195
TNM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-205
Czech Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-209
SonRoad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-211
HJ 2.4 (2009) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-213
Railroad Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-215
Schall 03 (1990) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-221
Schall 03 (2014) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-225
Nordic Prediction Method (1996) . . . . . . . . . . . . . . . . . . 6-229
CRN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-233
SRM II . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-235
NMPB-Fer 1996 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-237
NMPB-Fer 2008 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-239
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CNOSSOS-EU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-243
FTA/FRA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-245
Aircraft Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-249
Optimizable Source Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-251
Adjustment of the Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-253
Selecting Data for the Calculation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-257
Calculation Protocol. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-259
Compact Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-271
Multithreading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-273
Multiple Source Effect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-275
Monetary Evaluation of Noise according to BUWAL . . . . . . . . . 6-281
QSI - Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-282
QSI - Statistical Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-289
Batch Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-297
PCSP - Program Controlled Segmented Processing . . . . . . . . . . . . . . 6-303
Chapter 7 - Import
Import Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-3
Allocate Object Type to Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-5
Import only Section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-7
Importing selected Object Types . . . . . . . . . . . . . . . . . . . . . . . . . 7-11
Coordinate Transformation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-13
Unknown Attributes to Memo-Variable . . . . . . . . . . . . . . . . . . . . . 7-29
Process Ring Polygons . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-33
Import Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-35
CadnaA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-37
ArcView . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-39
Atlas GIS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-43
MicroStation-DGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-45
AutoCad-DWG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-47
AutoCad-DXF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-49
SketchUp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-61
EDBS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-69
GML (UK) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-71
CityGML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-73
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Open Street Map XML . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-77
MapInfo . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-85
Sicad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-87
Special Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-89
Stratis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-91
WINPUT-DGM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-95
Building Height Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-97
ASCII-Objects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-99
ASCII-Grid DTM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-107
ASCII-Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-109
Third-Party Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-111
Import / Export of Numbers of Trains . . . . . . . . . . . . . . . . . . . . . 7-113
Import via ODBC Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-115
Chapter 8 - Digitizer
Digitizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-3
Digitizing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-5
Tablet Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8-9
Chapter 9 - Graphics
Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-3
Coordinate Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-7
Object Snap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-9
Coordinate System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-11
Object Appearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-13
General Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-21
Symbol Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-25
Line Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-27
Line of Symbols Tab. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-29
Fill Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-31
Fill with Symbols Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-33
Fill with Hatch Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-37
3D Tab . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-39
Dialog Color . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-41
Default Object Appearance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-49
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Edit Toolbar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-51
Layer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-53
Fix Objects. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-55
Auxiliary Polygon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-57
Section. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-59
Settings for Objects with Frames. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-61
Text Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
Level (dB) Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-69
Symbol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-71
Station Mark . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-77
Cross Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-79
3D-Wire Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-81
3D-Special View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-85
Menu Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-91
Miscellaneous . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-99
Chapter 10 - Bitmaps
Insert Bitmaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-5
Bitmap Size and Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-7
Import Bitmap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-11
Delete Bitmap . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-17
Web-Bitmaps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-19
Chapter 11 - Tables
Object Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-3
Buttons in Object Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-11
Editing Object Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-13
Changing Column Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-19
Result Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-23
Editing the Result Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-25
Chapter 12 - Libraries
Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-5
Sound Level Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-7
Sound Reduction Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-23
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Absorption Spectra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-27
Road Surfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-31
Modify Spectrum . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-33
SET-S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-39
Diurnal Patterns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-47
Symbol Library. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-51
Text Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-63
Color Palettes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-67
Default Color Palettes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-77
Library Manager . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-79
Purge Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-81
Chapter 13 - Print & Export
Designing and printing the Graphics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
Plot-Designer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-3
PlotDesigner - Cell Types. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-17
Cell Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-21
Print Graphics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-35
Print Graphics using a Template File (outdated) . . . . . . . . . . . . 13-37
Designing & Printing Reports and Tables . . . . . . . . . . . . . . . . . . . . . . . 13-39
Printing Reports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-41
Template Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-45
Print Preview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-51
Export . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-53
AutoCad DXF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-55
ArcView (*.shp). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-57
ArcView-grid (*.asc, *.hdr) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-63
Bitmap Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-65
Text Files (*.txt, *.rtf). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-67
Word Document (*.docx) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-69
GoogleEarth . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-71
QSI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-75
CadnaA - BASTIAN - link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13-77
Chapter 14 - Project Organization
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ObjectTree . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-3
Variants. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-15
Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-21
Defining Groups. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-23
Partial Sound Levels of Groups. . . . . . . . . . . . . . . . . . . . . . . . . 14-27
Date Interval of Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-29
Folders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-31
Dynmap: The dynamic Noise Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-33
Prototype File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-39
Automatic Saving of Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-41
Automatically generated Text Blocks . . . . . . . . . . . . . . . . . . . . . . . . . . 14-43
Project Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-45
Calculation Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-47
Chapter 15 - Options X & XL
Object-Scan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-3
Scanning into Single Values . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-13
Scanning into Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-16
Scanning into the Grid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-19
Scanning into a Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-23
Conflict Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-25
Grid Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-27
Population Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-33
Monetary Evaluation according to BUWAL. . . . . . . . . . . . . . . . . . . . . . 15-37
Application to Areas of Designated Use . . . . . . . . . . . . . . . . . . 15-38
Loss in value as a single value . . . . . . . . . . . . . . . . . . . . . . . . . 15-43
Loss in value for all areas of designated land-use . . . . . . . . . . 15-45
Loss in value on a grid map. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-48
Close Polygons. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-49
Delete Height Points . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-55
Lua Scripting Language . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-57
Introduction to Lua. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-59
Syntax and Data Types . . . . . . . . . . . . . . . . . . . . . . . . . 15-59
Operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-61
Declaration and scope of variables . . . . . . . . . . . . . . . . 15-62
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Program flow: control structures & loops . . . . . . . . . . . . 15-64
Lua and CadnaA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-67
Validity of CadnaA-Lua-Objects . . . . . . . . . . . . . . . . . . . 15-79
Handling of Variants in CadnaA-Lua . . . . . . . . . . . . . . . 15-79
Addressing Evaluation Parameters in CadnaA-Lua . . . . 15-81
Symbols for Lua-Preset-Files . . . . . . . . . . . . . . . . . . . . . 15-81
Action „Lua Command“ . . . . . . . . . . . . . . . . . . . . . . . . . 15-82
LUA-Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-84
Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-89
Commands on Project Level . . . . . . . . . . . . . . . . . . . . . 15-89
Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-91
Grid and Grid Arithmetics . . . . . . . . . . . . . . . . . . . . . . . . 15-92
Grid Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-93
Table-Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-95
CadnaA-Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-97
Polygon-Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-98
Polygon-Vertex-Object (Polygon point) . . . . . . . . . . . . . 15-99
Partial Level . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-99
Variants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-100
Building Noise Map . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-101
Configuration of Calculation . . . . . . . . . . . . . . . . . . . . . 15-101
3D-Special . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15-102
Global Variable CLOSE_DIALOG... . . . . . . . . . . . . . . . 15-104
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CadnaA - Reference Manual
License Agreement XV
License Agreement
Important notice: Please carefully read this software license agreement before using the software. By installing the software, you agree to be bound by
the terms and conditions of this license agreement. If you do not agree to all
of the terms and conditions of this license agreement, you are not allowed to
use the software.
1.
SUBJECT MATTER OF THE AGREEMENT: DataKustik GmbH
grants the customer a non-exclusive right to use for the software including its documentation. A customer is a natural or legal person. Subsidiaries or affiliated companies are separate legal entities and therefore
separate customers. The right of use is granted for one customer only.
The property right and the copyright in the software do not pass to the
customer. The license is issued for use on one single computer workstation. For any further computer workstation, a separate license agreement will be required.
2.
COPY PROTECTION: The software is copy protected with a dongle.
The license dongle represents the value of the software and cannot be
replaced in case of loss. The DataKustik GmbH takes no responsibility
or obligation for the purchased license dongle. The customer shall bear
full responsibility in case of loss and may purchase a new license according to the current price conditions.
3.
COPY PROHIBITON: Neither the licensed software nor the documentation, in whole or in parts, may be copied. The only exception to
this rule is the generation of a machine-readable copy of the software
for backup or archiving purposes. Any copy made by the customer for
these purposes must include all copyright or other proprietary notices
contained on the original.
4.
ASSIGNMENT AND TRANSFER: The assignment to third parties of
rights and obligations arising out of this license agreement, and the
transfer of the software for use is subject to prior express written per-
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XVI License Agreement
mission of DataKustik GmbH. In particular the customer may not rent,
lease, lend or sublicense the software without prior express written permission of DataKustik GmbH. The splitting of one license bundle (client-server-license) is subject to prior written permission of DataKustik
GmbH.
5.
USE OF TRADEMARKS: The customer is permitted to use the trademarks and commercial names used by DataKustik GmbH to identify
printouts, provided that (a) these printouts were produced by the
licensed software using an electronic printing medium, (b) these trademarks and commercial names are identified in the same way as done so
by DataKustik GmbH, and (c) the customer stops using these trademarks and commercial names upon termination of this license agreement.
6.
PROHIBITION OF MODIFICATION: The customer may not modify the licensed software in any way or have it modified by third parties.
The customer may not decompile, reverse engineer, or disassemble the
software or any part thereof.
7.
UNAUTHORISED USE: The customer undertakes to ensure that his
employees and any other person subject to the customer's instructions,
having access to the licensed software, comply with all obligations of
safeguarding and the duty of care and diligence arising out of this agreement. The customer furthermore undertakes to ensure that no person
gains access to the licensed software with the aim of deriving the source
code. If the customer becomes aware of any such persons as indicated
in the first sentence of this clause, using the software in violation of the
obligations of safeguarding and the duty of care and diligence mentioned, he shall immediately take any possible action to prevent such use
contrary to agreement. He shall inform DataKustik GmbH in writing
of any such use contrary to agreement, should it continue nonetheless.
8.
INDEMNITY: DataKustik GmbH is entitled to the protection rights
and the copyright in the licensed software. The customer can be held
liable by DataKustik GmbH for any violation of such protection rights
which he is answerable for.
CadnaA - Reference Manual
License Agreement XVII
9.
WARRANTY: The customer recognises that errors in the software and
the pertinent documentation cannot be excluded given the state of the
art. If, within 30 days from delivery to the customer, the customer
asserts any deviation of the software from the software specifications/
description, he has the right to return the defective software including
the dongle to his supplier, and to demand delivery of a new software
version. If remedial measures cannot be taken or fail, the customer has
the right to demand a cancellation of the agreement. In this case, the
customer shall destroy any and all copies that he may have generated. In
states where national legislation requires a term of notice of defect of
more than 30 days, that legally provided term shall be taken to apply, if
the software is purchased and used there. Any further warranty claims
are expressly excluded. DataKustik GmbH neither warrants that the
software features satisfy the customer's requirements nor that they are
compatible in the selection made by the customer. Any liability for lost
profit, for damage to or loss of saved data and for any other indirect or
consequential damages is also excluded, unless resulting from grossly
negligent or wilful action by DataKustik GmbH. Any warranty, liability
or indemnity, etc. promised by a third party (e.g. by a distributor) to be
granted by DataKustik GmbH is not binding for DataKustik GmbH.
10. PROTECTION RIGHTS OF THIRD PARTIES: If the customer is
held liable by a third party because of an alleged violation of a patent
right, copyright, or any other protection right that said third party may
have in the licensed software, DataKustik GmbH shall immediately be
informed in writing of the alleged violation of protection rights, and
DataKustik GmbH shall be supported sufficiently in any lawsuit. If the
customer is held liable by a third party in this way, DataKustik GmbH
has the right to choose, at its own discretion, to either provide the customer with the appropriate license by the third party in question, to
modify the licensed software, to supply the customer with an equivalent
different software, or to take back the licensed software, in which case
the license fees shall be fully reimbursed to the customer. DataKustik
GmbH is not liable for violations of protection rights which are due to
the fact that the customer altered or modified the licensed software to
CadnaA - Reference Manual
XVIII License Agreement
suit his needs, or that the licensed software is used or sold in combination with other software, hardware or consumables not supplied by
DataKustik GmbH. This material liability is the total of any liability
assumed by DataKustik GmbH for violations of any patent right, trademark right, copyright or other intangible property rights.
11. SOFTWARE UPDATES: As an error-free data exchange of our software can only be granted if the software of one customer is at the same
version level on all computer workstations, DataKustik always supplies
the most recent version of the licensed software to the customer. In the
case of acquiring additional license rights, the customer is obliged to
update the existing licenses beforehand. A parallel use of different versions within the same customer is not allowed for the same reason.
DataKustik GmbH reserves the right to charge the customer with additional license fees for such updated versions.
12. LEGAL INVALIDITY OF CONTRACTUAL PROVISIONS: Should
one single or several provisions of this agreement be or become invalid,
this shall not affect the effectiveness of the remaining provisions of the
agreement. The invalid provision(s) will then have to be re-interpreted
or supplemented in such a way that the originally intended commercial
purpose is lawfully achieved.
13. DISCLAIM: This contract, including all provided documents, represents the full agreement between the parties. Collateral agreements do
not exist. All references or information by the contracting party with
regard to the validity of his terms and conditions is herewith explicitly
rejected.
CadnaA is a registered trademark of DataKustik GmbH, Germany.
CadnaA - Reference Manual
Index XIX
Index
Lua commands and functions are not indexed!
Numerics
3D-Reflector 3|71
3D-Special View 9|85
calling 9|86
Editing Objects 9|88
Generate Camera Line 9|87
Ground Texture 9|88
Menu Commands 9|91
moving in 9|87
Text Boxes in 3D 9|89
3D-Symbol 9|71
library 12|56
Options 9|73
A
Absorption
Alfa 3|2
Spectra 12|27
Acoustic Transparency 3|11
Additional Width left/right 2|87
Adjusting column width 11|8
Affine Transformation 7|17
Air Attenuation, user-defined 6|105
Aircraft Tab 6|249
Angle Scanning 6|48
Appearance
CadnaA - Reference Manual
of Grid 5|31
of Objects 9|13
ArcView 7|39, 13|57
ArcView ASCII Grid 7|41
Area (m²) 2|20
Area of Designated Land Use 5|13
Area sources follow terrain 6|74
Areas of Equal Sound Level 5|32
Arithmetic see Building Noise Map
Arithmetics see Grid Arithmetics
ASCII-file 4|17
ASCII-Grid DTM 7|107, 7|109
Assign Facade Bitmaps
example 3|28
Assign Roof Bitmap
example 3|29
Atlas GIS 7|43
Attenuation 2|14
Auralisation 2|294
Auto save 14|41
Auto-Assignment of Objects 14|9
AutoCad 13|55
AutoCad-DWG 7|47
AutoCad-DXF 7|49
Automatic Saving of Files 14|41
Auxiliary Polygon 9|57
Average Height (m) 2|94, 2|165
B
Background beyond the Limits 9|100
XX Index
Barrier 3|41
cantilever 3|47
crowning 3|47
Floating Barrier 3|43
optimize noise barriers 3|91
with special Crowning 3|47
Barrier Coefficient 6|104
BASTIAN, connection with CadnaA 13|77
Batch Operation 6|297
Bitmap 7|89, 10|1
calibrate 10|7
convert to monochrome 10|9
fix Bitmap 10|9
Formats 10|11
generate height point cluster 4|63
Import from GoogleEarth 10|12
show bitmap 10|9
transforming Bitmaps 10|10
Transparency 10|9
Web-Bitmaps 10|19
Bridge 3|61
Building 3|3
acoustic transparency 3|11
Deactivate Point Objects inside 3|7
Edit Facades 3|21
facade bitmaps 3|24
Generate Building 3|39
Height Points 7|97
Level-Difference-Map 5|83
Noise Maps of 5|69
Result Table, Building Noise 5|79
roof bitmap 3|27
Snap Point to Building Facade 3|17
Building Evaluation 5|61
Building Height Points 7|97
Built-Up Areas 3|65
Built-Up Areas & Foliage 3|65
C
Cadna.dat 12|3
Calc Width of Roads 2|95
Calculation 6|275
Batch Operation 6|297
Compact Protocol 6|271
Grid 5|39
HAP 6|275
Limits 9|3
QSI 6|282, 6|289
Selecting Data for 6|257
Calculation Area 6|257
Calculation Protocol 6|259
Canceling Grid Calculation 5|40
cantilever 3|47
Check Consistency 5|9
CityGML 7|71
Class Width 5|35
Closing Buildings 15|49
Color Palette
Defining a new palette 12|67
dialog options 12|71
Example 12|73, 12|74
Import old Palette-File 5|36
option Progressive Colors 12|71
Color Palette "default" 5|33
Color Palette "file" 5|33
Color Palettes 5|33, 12|67
Compact Protocol 6|271
Configuration 6|31
Conflict Maps 15|25
Contour Lines 4|11
displaying triangulated lines 6|72
generate from height points 4|51, 4|57
Convert to monochrome (for PDF) 10|9
Coordinate Grid 9|7
CadnaA - Reference Manual
Index XXI
Coordinate System
global 9|11, 10|14
Median Strip 9|12
NTv2 reference systems 9|11
Offset 9|12
User-defined coordinate system 9|12
Coordinate Transformation 7|13
Affine Transformation 7|17
General Transformation 7|20
Interactive Transformation 7|22
NTv2 reference systems 7|18
Coordinates
General Transformation 7|20
Copy Data Records 11|9
Correction 2|14
Country Tab 6|33
Counts, MDTD 2|82
Criteria for Calculation of Reflections
min. Dist. Source - Reflector 6|85
Crossings with Traffic Lights 2|171
Crowning 3|47
Cylinder 3|69
D
Data 11|4
Data Set
Delete 11|4
Edit 11|4
Database
ODBC interface 7|115
Deactivate Point Objects in Buildings 3|7
Defining 12|67
Delete 4|17
Grid 5|19
Grid Points 5|29
Poly points via height z 7|20
CadnaA - Reference Manual
Delete Height Points 15|55
Deviation 6|42
Dialog Grid Appearance
Section "Color Palettes" 5|31
Dialog Railway 2|181
Digital Terrain Model
configuration tab
Fit objects to DTM 4|39, 4|45
Standard Height 6|71
Digitizer 8|3
Test 8|3
Digitizing
Calibrate Digitizer 8|6
Directivity 2|51
Import via ODBC 2|64
Paste via clipboard 2|64
Sound Radiation by Chimneys 2|57
Displaying Sound Rays 6|23
Displaying triangulated terrain contours 6|72
Distance Multiple Reflection 2|94, 2|165
Distance of the outer lanes 2|75
Distance Source to Reflector 6|85
Diurnal Pattern 2|83
DTM see Digital Terrain Model
DXF 13|55
Dynmap 14|33
E
EDBS 7|69
Edit Facades 3|21
effect related substitute level 6|275
Embankment 3|87
Emission
Lm,E Road 2|82
Emission Type 2|11
Entry in CADNAA.INI 6|299
XXII Index
Evaluation 15|27
Evaluation Parameter Tab 6|65
Exact Count Data 2|83
Example
Assign Facade Bitmaps 3|28
Assign Roof Bitmaps 3|29
Defining a group 14|24
Groups & Partial Sum Level 14|24
Level differences for Buildings 5|83
Example Files
SmallCity01.cna 15|13
SmallCity02.cna 15|16, 15|19
SmallCity03a.cna 15|19
SmallCity03b.cna 15|22
SmallCity04.cna 15|23
Explicit Edges Only 6|72
Export 13|53
ArcView 13|57
ArcView Shape 13|57
DXF 13|55
GoogleEarth 13|71
RTF 13|67
Text file TXT, RTF 13|67
TXT 13|67
Exporting
Template Files 13|45
F
facade bitmaps 3|24
repeat in X/Y 3|25
repeat on all facades 3|25
Fault Lines 4|19
Fit Objects to DTM 4|39, 4|45
Fix Bitmap 10|9
Folding Markers 13|24
Frame
Station Mark 9|77
Symbol 9|71
Frames 9|61
G
General Tab 6|35
Angle Scanning 6|48
Mithra Compatibility 6|50
Ray Tracing 6|48
General Transformation 7|20
Generate Building 3|39
Generate Rays 5|5
Generate Tiles 6|304
Geodetic Transformation 7|18
Median Strip 7|19
Source Coordinates 7|19
Target Coordinates 7|19
Geometry 4|21
GML 7|71
GoogleEarth 13|71
KML-File 13|73
KMZ-File 13|73
GoogleEarth see Import from 10|12
Graphics
Bitmap 10|1
Coordinate Grid 9|7
print 13|35
Settings for Objects with Frames 9|61
Template Files 13|45
update during drag 9|5
Vector graphics 10|1
Grid
Arithmetics 5|41
Calculation 5|39
Conflict Maps 15|25
Delete 5|19
CadnaA - Reference Manual
Index XXIII
Evaluation 15|27
from Iso-dB-lines 5|51
Resample 5|22
Specification 5|25
vertical grid 5|57
Grid Appearance
Section "Color Palettes" 5|31
Grid Arithmetics 5|59
Grid Calculation
Canceling 5|40
Resuming 5|40
Grid interpolation 6|45
Grid of Receivers 5|17
Ground Absorption
Ground Absorption Areas 3|63
Ground Absorption Areas 3|63
Groups
Hierarchy of Groups 14|24
Partial Sound Level 14|27
H
HAP-Calculation 6|275
Height of Parapet left/right 2|87
Height Points 4|15, 4|17
Delete Height Points, Multifile 15|55
generate cluster from bitmap 4|63
Import ASCII-file 4|17
Hold Value 9|69
I
Import 4|17
Allocate Object type to layer 7|5
Format 7|35
formats 7|35
Height Points 7|95
CadnaA - Reference Manual
Importing in Section only 7|7
Importing selected Object Types 7|11
Layer 7|1
MITHRA 7|89
Mithra Trains 7|89
NMPB08 Trains 7|89
Number of Trains 7|113
ODBC 7|115
Options 7|1, 7|3
QSI 7|89
T-Mobil 7|89
Import / Export Number of Trains 7|113
Import format
CityGML 7|71
GML 7|71
Import formats
ArcView 7|39
ASCII-Objects 7|99
Atlas Gis 7|43
AtlasGIS 7|43
AutoCad-DXF 7|45, 7|47, 7|49
Bitmap 7|89
Building Height points 7|97
CadnaA 7|37
CST 7|91
EDBS 7|69
MapInfo 7|85
NTF 7|89
Slip 7|89
SOSI 7|89
special formats 7|89
Stratis 7|91
third-party software 7|111
WINPUT 7|95
Import old Palette-File 5|36
Import Options
Affine Transformation 7|17
XXIV Index
Allocate object type to layer 7|5
General Transformation 7|20, 7|22
Import only Section 7|7
Importing selected Object Types 7|11
Inclined Sources 2|13
Individual Assignment of Objects 14|9
Industrial source
horizontal area source 2|4
Line Source 2|3
Point Source 2|3
vertical area source 2|4
Industrial source dialog
directivity index 2|25
Emission value A-weighted 2|11
K0 w/o ground 2|25
normalized A 2|16
radiating area (m²) 2|20
Industry Tab 6|87
Industry tab 6|87
relative humidity 6|105, 6|113, 6|119,
6|130, 6|134, 6|143, 6|152
Wind Speed for Chimney Directivity
6|113, 6|130
information on terrain models 6|73
Insert Bitmaps 10|5
Interpolation of height z 7|21
K
KML-File 13|73
KMZ-File 13|73
L
Labeling of Printing Ranges 13|47
LAFmaxX% 6|172
Land Use 5|13, 5|15
Lateral Diffraction 6|93, 6|94, 6|111, 6|151
Lateral Slope 2|82
Layer (for Import) 7|1
Level Box 9|69
Level Range 5|35
Level, Specifying Precision 5|8
Level-Difference-Map Building Noise 5|83
LfU-Study (2007) 2|277
Libraries
Absorption Spectra 12|27
global placed on server 12|3
user-defined data 12|3
Libraries Manager 12|79
Lift Sources to Ground-Niveau 6|73
Limits
Background 9|3
calc 9|3
Line of Fault 4|19
Line to Point see Text Box
Lines of Equal Sound Level 5|32
Local Train List 2|193, 2|210, 2|216, 2|249
Long Straight Road 2|99
Lower/Upper Limit 5|35
M
MapInfo 7|85
Margins 13|24
Marker size 9|99
Match Points 7|15
max. Error 6|35
Median Strip 7|19, 9|12
menu File|Database 7|115
MicroStation-DGN 7|45
min. Dist. Source - Reflector 6|85
Miscellaneous
Background beyond the Limits 9|100
CadnaA - Reference Manual
Index XXV
Marker size 9|99
Segment Length 9|100
Update during Calculation of Grid 9|100
Update during Drag 9|100
MITHRA 7|89
Mithra Compatibility 6|50
Model of Terrain
Area sources follow terrain 6|74
Explicit Edges Only 6|72
general information 6|73
Lift Sources to Ground-Niveau 6|73
Triangulation 6|71
Modify Objects
ObjectTree 14|13
Monetary Evaluation BUWAL 15|37
Mouse
transform objects s. objects
Multifile 15|55
Multiple Source Effect 6|275
Multithreading 6|273
N
Noise Map
PCSP 6|303
Noise Maps of Buildings 5|69
Noise Source
Optimisable Source 2|299
Nord 96 (Road)
LAFmaxX% 6|172
Sampling Interval (s) 6|172
normalized A 2|16
NTF 7|89
NTv2 reference systems 7|18, 9|11
Number of Trains 7|113
CadnaA - Reference Manual
O
Object Appearance 9|13
3D tab 9|39, 9|49
Fill tab 9|31
Fill with Hatch tab 9|37
Fill with Symbols tab 9|33
General tab 9|21
Line of Symbols tab 9|29
Line tab 9|27
Symbol tab 9|25
Objects
Tables 11|3
transform using the mouse 7|22
with frames 9|61
Objects’s Geometry 4|21
Object-Scan 15|3
ObjectTree
Assigning Objects 14|9
Auto-Assignment of Objects 14|9
Copying Objects 14|12
Deactivated Objects 14|10
Definition 14|3
Definition and Editing 14|8
Example 14|8
Indiv. Assignment of Objects 14|9
Modify Objects 14|13
Partial Level 14|12
Sound Power Level 14|11
Obstacles
3D-Reflector 3|71
Barrier 3|41
Bridge 3|61
Building 3|3
Built-Up Areas 3|65
Cylinder 3|69
Embankment 3|87
XXVI Index
Foliage 3|65
ground absorption areas 3|63
reflection properties 3|1
Obstacles in Area Source not Shield 6|103,
6|112
ODBC interface 7|115
Offset 9|12
Offset-Values 9|12
Operating Time 2|21
Optimisable Source 2|299
Usability Function 2|302
Optimisable Source Tab 6|251
Optimized Area Sources 2|299
Option XL 15|1
closing buildings 15|49
Evaluation 15|27
Facade points 5|77
Monetary Evaluation BUWAL 15|37
Object-Scan 15|3
Population Density 15|33
Options
Coordinate Grid 9|7
for 3D-Symbols 9|73
Land Use 5|15
P
Palette Entry 12|69
Parking Lot
LfU-Study (2007) 2|277
RLS-90 2|275
SN 640 578 2|285
Partial Levels 5|11
Partial Sound Level 14|24, 14|27
Partition Tab 6|51
RBLärm 92, method 1 6|54
Pass-by
level for line sources 2|289
video 2|298
paste 11|9
PCSP 6|303
Generate Tiles 6|304
User-defined Tiling 6|305
PDF s. Bitmap, convert
Population Density 15|33
Precision of Levels 5|8
Preview 13|51
Zoom 13|51
Print
Preview 13|51
Print Graphics 13|35
Reports 13|41
Template Files 13|45
Printing
Reports 13|41
Template Files 13|45
Printing Reports 13|41
Program Controlled Segm. Processing 6|303
Progressive Colors 5|35
Projection with large sources 6|9
Protocol 6|259
Purge Tables 12|81
Q
QSI
Import 7|89
Statistical Analysis 6|282, 6|289
R
radiating area (m²) 2|20
Railroad Tab 6|215
Railway 2|179
CadnaA - Reference Manual
Index XXVII
traffic-count calculator 2|269
train classes user-defined 2|255
Raster factor 6|51
Ray Tracing 6|48
Rays see Generate Rays
RBLärm 92, method 1 6|54
Receiver 5|3
Check Consistency 5|9
Generate Rays 5|5
suppress empty partial levels 5|12
Receiver Grid 5|17
Reference Time Tab 6|59
Reflection 6|13
Absorption coefficient alpha 3|2
Configuration tab 6|77
of the 1st Order 6|15
Properties of Obstacles 3|1
Reflection Tab 6|77
Reflections
of Higher Order 6|19
relative humidity 6|105, 6|113, 6|119, 6|130,
6|134, 6|143, 6|152
Resample (Grid) 5|22
Result Table
Building Noise 5|79
Edit 11|25
Resuming Grid Calculation 5|40
Rich Text Format (RTF) 13|67
RLS-90 2|275
Road 2|73
Average Height (m) 2|94, 2|165
Calc Width of Roads 2|95
curb-to-curb 2|75
Distance (m) 2|94, 2|165
Distance of the outer lanes 2|75
Emission Lm,E 2|82
Gradient (%) 2|84
CadnaA - Reference Manual
Road Width 2|75
Speed 2|84
Station Mark 9|77
Traffic Density 2|82
Traffic Lights 2|171
widening from 1 to 2 lanes 2|78
widening of lanes 2|78
width, curb-to-curb 2|75
Road Tab 6|159
Road Type 2|82
road width, curb to curb 2|75
roof bitmap 3|27
roof bitmaps
texture alignment 3|27
Roof Edge see Crowning
Rotation and Displacement 7|14
RTF 13|67
S
Sampling Interval (s) 6|172
Saving 14|41
Scale
Vertical Grid 5|58
Scale Dimension 9|65
Search Radius (m) 6|38
Search Radius for Reflectors 6|79
Section 9|59
Segment Length 9|100
segmentation RB-Lärm 92, method 1 6|54
Selecting Data for the Calculation 6|257
Self-Screening 2|187
Station from/up to 2|88
Shape 13|57
sigma 6|42
Slip 7|89
SN 640 578 2|285
XXVIII Index
Snap Point to Building Facade 3|17
Sorting columns 11|7
Sosi 7|89
Sound Power Level 2|11
Sound Rays 6|23
and Reflection 6|3
from extended Sources 6|7
from Point Sources 6|5
Source Coordinates 7|19
Source dialog
Steady-State 2|21
Special Calculations 6|275
Special Formats 7|89
Spectra
Absorption-Spectra 12|27
Diagram 2|11
Spectrum Monitor 2|11
Speed 2|84
Speed Limit 2|84
Standard Deviation 6|42
Standard Height 6|71
Station
from/up to see Self-Screening
Station Mark 9|77
Status bar
Information 9|5
Storeys
string variable 5|81
Stratis 7|91
Strictly according to Schall 03 6|221
String variable
for Building Noise Map 5|82
substitute level
acc. to VDI 3722-2 6|275
Symbol 9|71
Main Aspect Ratio 9|72
Scale Dimensions 9|72
Synchronization 11|4
T
Table
adjusting the column width 11|8
copy & paste data records 11|9
delete Data Record 11|4
sort column 11|7
Tables 11|3
purge tables 12|81
Tabs (Object Appearance)
3D 9|39, 9|49
Fill 9|31
Fill with Hatch 9|37
Fill with Symbols 9|33
Line 9|27
Line of Symbols 9|29
Symbol 9|25
Tabs(Object Appearance)
General 9|21
Target Coordinates 7|19
Temperature 6|105, 6|113, 6|119, 6|130,
6|134, 6|143, 6|152
Template Files 13|45, 13|46
Labeling of Printing Ranges 13|47
Tennis source 2|67
Text block
how to enter a 12|64
Text Box 9|63
display in 3D 9|89
Line to Point 9|66
Third-Party Software 7|111
Tiling a Project 6|303
T-Mobil 7|89
Topography 4|1
Building Height Points 7|97
CadnaA - Reference Manual
Index XXIX
Contour Lines 4|11
Fault Lines 4|19
Height Points 4|15
Traffic Lights 2|171
Traffic-Count Calculator 2|269
Train Classes and Penalties 2|182
Train Classes User-defined 2|255
Transformation 7|13
Affine Transformation 7|17
Directivity vector 7|13
General Transformation 7|20
Geodetic Transformation 7|18
Interactive Transformation 7|22
Interpolation of height z 7|21
Match Points 7|15
Rotation and Displacement 7|14
Transforming Bitmaps 10|10
Transparency
acoustic (%) 3|11
Bitmap 10|9
Triangulation 6|71
TXT 13|67
U
Uncertainty 6|41
Update automatically/ Hold Value 9|69
Update during Calculation of Grid 9|100
Update during Drag 9|5, 9|100
Usability Function 2|302
User-defined coordinate system 9|12
V
VDI 3722-2 see Multiple Source Effect 6|275
Vector graphics 10|1
Vertical Grid 5|57
CadnaA - Reference Manual
Grid Arithmetics 5|59
Scale 5|58
Video 2|298
View see Import from GoogleEarth 10|13
W
Web-Bitmaps 10|19
Wind Speed for Directivity 6|113, 6|130
WINPUT-DGM 7|95
XXX Index
CadnaA - Reference Manual
Chapter 1 - Introduction
Chapter 1 - Introduction
CadnaA is a software program for the calculation and the assessment of
noise and air pollution. The program fulfills the requirements for
professional experts.
The software calculates and predicts the noise immission in the
neighborhood of:
•
•
commercial and industrial sites,
sports and leisure facilities,
and of traffic systems like
•
•
•
road and railways,
airports and landing strips, or
any other noisy facilities.
CadnaA is suitable for noise prediction in local studies as well as for detailed
analyses of mapping noise scenarios in large cities (option CadnaA-XL).
Powerful features include incredible screen displays, handling and output of
graphical grids and the use of scanned bitmap plans (option CadnaA-BMP).
CadnaA enables automatic optimization of barriers and the automatic allocation of noise quota (option CadnaA-BPL). Aircraft noise in the vicinity of
airports, landing strips and related facilities is calculated with the additional
option CadnaA-FLG.
The option CadnaA-APL („Air Pollution“) extends the range of application
to the calculation, the assessment, and the presentation of air pollutants distribution.
Basic to all, CadnaA has the ability to import and export data from and to
third-party software (e.g. ArcView, MapInfo, DXF, or from databases via the
ODBC-interface).
CadnaA - Reference Manual
11
1
2
1
1
Chapter 1 - Introduction
The sound level during pass-by’s with time history and auralization of moving
sources, the different 3D-views of your project when moving through, the
PCSP (Program Controlled Segmented Processing) to accelerate calculation
of large projects, the groups and the ObjectTree are just some highlights of
CadnaA.
CadnaA - Reference Manual
13
Chapter 1 - Introduction
1.1 Structure of CadnaA documentation
1.1
Structure of CadnaA documentation
1
The range of documentation provided with the CadnaA software consists of
the following parts:
Document
Contents
Introduction
installation, editing of objects, modes
of calculation, modeling industrial,
road, and railway noise, basic import
features & grouping concept, Modify
Objects & context menu actions/
commands
Reference manual (present
manual)
detailed description of all dialogs and
their options (sources, obstacles,
topography, immission), configuration dialog, import/export,
graphics/bitmaps, tables & libraries,
project organization
manual „Attributes, Variables,
and Keywords“
listings of object attributes, variables
& keywords, handling of string operations, operators & functions, protocol abbreviations
These documents are revised with every new release of CadnaA regarding
new features and also with respect to modifications or amendments of
existing features.
The reference manual contains the documentation and description of all
CadnaA features, excluding the installation procedure, the input and the
editing of objects, and the actions/commands on the dialog Modify Objects
and on the context menu. Those features are explained in the introductory
manual besides an introduction to all modes of calculation and all noise types.
CadnaA - Reference Manual
Structure of this
manual
4
1
1
Chapter 1 - Introduction
1.1 Structure of CadnaA documentation
Chapter 2 describes for each source type all available options on the
corresponding object dialog, including short examples if necessary. The subchapters for each source type (industry, road, railway) start by a chapter explaining input data independent from the selected standard, followed by
standard-specific explanations.

Due to numerous standards and guidelines implemented in CadnaA,
and with respect to the possible revision of national procedures
between two software releases, DataKustik cannot guarantee in any
case the actuality of the specifications given. Particularly, the
specifications cannot substitute buying and studying the original paper.
Indications on the official supplier can be found in the references
(chapter 1.4 "Literature").
In chapter 3 to 4, the reference manual treats all obstacles including the
topography.
In chapter 5 all types of noise evaluation in CadnaA are described. This
includes: the receiver point, the area of designated, the horizontal and the
vertical grid as well as the building evaluation. This chapter treats also the
features of the option XL as there are, e.g.: the map of conflicts, the grid
evaluation, the ObjectScan, and the population density.
Chapter 6 presents the principles of calculation applied in CadnaA,
particularly with respect to the configuration settings.
In Chapter 6, the basic principles of the calculations in CadnaA are explained. Furthermore, you will find here the description of the standardspecific configurations of calculation. The text is specific to each source type
with separate chapters for each implemented calculation procedure. In
addition, the other commands and features on the Calculation menu are described (e.g. multi-threading and batch operation by using PCSP.).
The chapter 7 covers the handling of all import formats available in CadnaA.
Chapter 8 treats the use of a digitizing board for the input of object geometry.
CadnaA - Reference Manual
Chapter 1 - Introduction
1.1 Structure of CadnaA documentation
The chapters 9 and 10 describe all available objects and procedures for
producing a graphic output in CadnaA, as well as the features for import and
scaling of external bitmaps.
Chapter 11 explains the features of the object’s tables while chapter 12 covers
their application within the local and global libraries.
The chapter 13 deals with the output of report files (for example as tables) or
as a graphic printout using the CadnaA-PlotDesigner. This includes the
export of geo-referenced projects to GoogleEarth™.
Chapter 14 deals with all aspects of project organization. This includes the
ObjectTree, used to define groups and the handling of variants.
In Chapter 15, the further features for evaluation provided by the options X
and XL are described (e.g. object scanning, conflict maps, grid evaluation,
population density). This includes also the features „Close Polygons“ and
„Delete Height Points“. Further, this chapter describes the features and
commands of the scripting language Lua in CadnaA.
CadnaA - Reference Manual
15
1
6
1
Chapter 1 - Introduction
1.1 Structure of CadnaA documentation
1
CadnaA - Reference Manual
17
Chapter 1 - Introduction
1.2 New Features of CadnaA 2018
1.2
New Features of CadnaA 2018
1
The list of new features offered by CadnaA 2018 is subdivided into the
following sections:
•
•
•
•
•
•
•
Calculation/Configuration
CadnaA-Objects
Further New Features
Miscellaneous
Import/Export
CadnaA-Options
Bug Fixing
•
ISO 9613: new type "Ground Absorption": "WEA interim (Agr=-3 dB)"
used by German Interim method for Wind Turbine Predictions (2015)
•
Railway ONR 305011, Semibel, FTA/FRA: new option "Calc maximum
Pass-By-Level" (based on Leq-based emission per unit length)
•
Road Nordic Prediction Method (1996): new option "Threshold" with
calculation of maximum Pass-By-Level to calculate NATs (Number above
Threshold)
•
"Evaluation Parameters" tab: selecting "f(x)" offers new parameters
Lden/Ln for evaluations acc. to VDI 3722
•
dialog "Multiple Source Effect" (Calculation menu): new option "Save
total in (Variant)" for sum-grid acc. to VDI 3722
•
grid calculation per batch for all variants (using CALC_RASTER=2, not
for PCSP)
•
Point, Line, Area Sources: new attribute TEINW_GANG (selects a
diurnal pattern)
•
object "Symbol": new scale bars available
•
Building Evaluation: dialog Exclude Facades now accepts up to 256
facades
CadnaA - Reference Manual
Calculation|Configuration
CadnaA-Objects
8
1
1
Further New Features
Chapter 1 - Introduction
1.2 New Features of CadnaA 2018
•
Bitmap: new option "Bitmap in internal memory" svaes the bitmap as
part of the CadnaA file
•
Bitmap: extended transparency features (e.g. by specifying transparency
and "white is transparent globally")
•
Road (CNOSSOS-EU): attribute STRO_ID selects road surface (e.g.
CNS_01 .. CNS_15)
•
Facade Points: new attribute FAC_EINW_xy (weighted per facade length
or not, all or just active ones)
•
Railway (Schall03-2014, CNOSSOS-EU, NMPB08-Fer): new attributes
GEFAELLE, MIND, MIND_I, SLAB_TRACK
•
new graphical user-interface:
 scalable object icons (on toolbox and on toolbar)
 scalable font in dialogs (Options|Miscellaneous menu)
•
dialog ObjectTree|Definition: button "Sync. Graphics" on ObjectTree
toolbar
•
new context menu command "Import here...": The origin (0,0) of the
imported data is placed at the coordinates of a point object or were the
mouse click occured.
•
Grid Arithmetics: now with access to grids in variants (coding:
RxVvvEvalParaNo, x=0..6, vv=01..16, EvalParaNo=1..4)
•
Multithreading (Calculation menu): offers now up to 64 threads
(requiring 64-Bit option)
•
command/action "Parallel Object": new option "Distance from curb/
border" for road and railway considers a specified additional width (dialog
Appearance/Road or on road's geometry)
•
dialog Modify Objects, new action "Break Lines": just breaks line/area
objects of the selected object type
•
dialog Modify Objects: conditions for string possible
•
geodetic transformation: offers now NTv2 reference systems (requires
that the respective gsb-files are copied to directory <cadnadir>/NTv2)
CadnaA - Reference Manual
19
Chapter 1 - Introduction
1.2 New Features of CadnaA 2018
•
dialog Building Noise Map (Options menu): new options "Facade
points acc. to VBEB" and "... acc. to CNOSSOS"
•
Grid|Delete menu: Holding CTRL key depressed deletes all grids in
variants.
•
dialog Modify Objects: With action "Delete" now default condition
match(ID$, "RAY*") deleting all rays
•
extended keyword #(File, ...): #(File, dpne).cna_autosave generates an
autosave-file
•
screen scaling uses "DPI aware" for all monitors: makes fonts and icons
bigger and easier to read
•
import formats "SOSI" and "CityGML": new option "Unknown
Attributes to Memo-Variables""
•
new export format DOCX: exports reports based on MS-Word template
DOCX (new, table specific keywords #(CUSTOM_TABLE, ...) and
#(COL, ...)
•
PlotDesigner (File|Print Graphics menu): new "Preview" button
•
printing the graphics per template file (File menu) still available for
existing graphics template files
•
Result Table: new string variable FAC_LEN, facade length per facade
point
•
option X/XL: new and extended LUA commands (e.g. import, grid
spacing, Exclude Facades, 3D-Special)
•
option FLG: new calculation procedure ECAC4
•
option FLG: selectable no. of corridor paths with ECAC3 and ECAC4
•
option 64-Bit: multithreading now for up to 64 threads
CadnaA - Reference Manual
1
Miscellaneous
Import/Export
CadnaA-Options
10
1
1
Bug Fixing
Chapter 1 - Introduction
1.2 New Features of CadnaA 2018
•
NMPB08-Fer: vertical directivity corrected (no absolute value), toggle
back per local text block OPT_OLD_CALC with text:
nmpb08_vdir_abs_x157
•
Concawe: ground absorption K3 now just consider ray path length across
absorbing round
CadnaA - Reference Manual
Chapter 1 - Introduction
1.3 Notations
1.3
Notations
1
The following table comprises all types of notations used in the CadnaAdocumentation.
setup
text to be typed in
RETURN,
CTRL,
DEL
keyboard keys
CTRL+v
key combinations
(e.g.: hold down the CTRL-key while typing the letter v)
down arrow key
arrow keys
(move cursor to left/right/up/down)
Program Files/Datakustik
directories
Grid|Appearance,
3D-Special
menus and commands
„Geometry“,
„TransLoss“
buttons in dialogs and other options in
dialogs
double-click,
double-clicking
Instructs you to rapidly press and release
the left mouse button twice.
•
The focal point requires an action or a
sequence of actions.

remark or comment
 Examples\
reference to file, use the indicated file path
to open the file
04_Topography\HP.cna
CadnaA - Reference Manual
1 11
12
1
Chapter 1 - Introduction
1.3 Notations
1
CadnaA - Reference Manual
1 13
Chapter 1 - Introduction
1.4 Literature
1.4
Literature
1
Standards & Guidelines
/1/
Concawe-report no. 4/81, „The propagation of noise from petroleum and petrochemical complexes to neighboring communities“, (Ref.AT 931), CONCAWE, Den Haag
May 1981
/2/
AR-INTERIM-CM, Adaptation and revision of the interim noise computation methods for the purpose of strategic noise mapping, Final Report, Part A, Reference: B43040/2001/329750/MAR/C1, 25 March 2003
/3/
IMAGINE Improved Methods for the Assessment of the Generic Impact of Noise in
the Environment, WP 7: Industrial noise sources, Adaptation of the Harmonoise engineering model to industrial noise sources, document IMA07MO-041126-CSTB01,
Date : 26/11/2004.
/4/
HARMONOISE, WP 2, Reference Model, Description of the Reference model, document HAR29TR-041118-TNO10, 22 December 2004.
/5/
Development of the HARMONOISE Point-To-Point Model, Prediction of Excess
Attenuation in Outdoor Noise Propagation, author: D. van Maercke/CSTB, presented
at Meeting Norwegian Acoustical Society, Kristiansand, 08.09.2006.
/6/
ECAC DOC 29: European Civil Aviation Conference Document 29, „Report on Standard Method of Computing Noise Contours around Civil Airports“, 2nd edition, 1997
/7/
ISO 3744 Acoustics - Determination of sound power levels of noise sources using
sound pressure - Engineering method in an essential free field over a reflecting plane
/8/
ISO 9613, Acoustics - Attenuation of sound during propagation outdoors,
Part 1 (1993-06): Calculation of the absorption of sound by the atmosphere,
Part 2 (1996-12): General method of calculation,
ISO International Organization for Standardization, Geneva (CH)
/9/
ISO 9614: Acoustics - Determination of sound power levels of noise sources using
sound intensity:
Part 1: Measurement at discrete points (as of 1993-06-03)
Part 2: Measurement by scanning (as of 1996-08-01)
Part 3: Precision method for measurement by scanning (as of 2002-10-22)
/10/
ISO 717: Acoustics - Rating of sound insulation in buildings and of building elements,
Part 1: Airborne sound insulation (ISO 717-1:1996)
Part 2: Impact sound insulation (ISO 717-2:1996);
ISO International Organization for Standardization, Geneva (CH)
CadnaA - Reference Manual
International
14
1
1
Germany
Chapter 1 - Introduction
1.4 Literature
/11/
ISO 11654 (1997), Acoustics - Sound absorbers for use in buildings - Rating of sound
absorption, ISO International Organization for Standardization, Geneva (CH)
/12/
ISO 3744:2010, Acoustics - Determination of sound power levels and sound energy
levels of noise sources using sound pressure - Engineering methods for an essentially
free field over a reflecting plane (as of 2010-09-22), ISO International Organization for
Standardization, Geneva (CH)
/13/
ISO 3745:2012, Acoustics - Determination of sound power levels and sound energy
levels of noise sources using sound pressure -- Precision methods for anechoic rooms
and hemi-anechoic rooms (as of 2012-03-16), ISO International Organization for Standardization, Geneva (CH)
/14/
ISO 3746:2010, Acoustics - Determination of sound power levels and sound energy
levels of noise sources using sound pressure -- Survey method using an enveloping
measurement surface over a reflecting plane (as of 2010-11-25), ISO International
Organization for Standardization, Geneva (CH)
/15/
EN 12354: Building Acoustics - Estimation of acoustic performance of buildings from
the performance of products,
Part 1 (1999): Airborne sound insulation between rooms;
Part 2 (1999): Impact sound insulation between rooms
Part 3 (1999): Airborne sound insulation against outdoor sound
/16/
COMMISSION DIRECTIVE (EU) 2015/996 of 19 May 2015 establishing common
noise assessment methods according to Directive 2002/49/EC of the European
Parliament and of the Council, ANNEX Assessment Methods for the Noise Indicators,
Official Journal of the European Union L168, Legislation Volume 58, 1 July 2015
/17/
RLS90, Richtlinien für den Lärmschutz an Straßen (Guidelines for Noise Control at
Roads, in German); Der Bundesminister für Verkehr, Abteilung Straßenbau, Ausgabe
1990, Verkehrsblatt 44 (1990)
/18/
Richtlinien für die Anlage von Straßen RAS (Guidelines for the construction of roads,
in German), Teil: Querschnitte RAS-Q Ausgabe 82, Forschungsgesellschaft für Strassen- und Verkehrswesen, Arbeitsgruppe Strassenentwurf
/19/
Richtlinien für die Anlage von Straßen RAS (Guidelines for the construction of roads,
in German), Teil: Querschnitte RAS-Q 96, Forschungsgesellschaft für Strassen- und
Verkehrswesen, Arbeitsgruppe Strassenentwurf
/20/
Rechenbeispiele zu den Richtlinien für den Lärmschutz an Straßen RBLärm-92
(Calculation Examples concerning the Guidelines for Noise Control at Roads, in German), Der Bundesminister für Verkehr Abteilung Straßenbau, Ausgabe 1992
/21/
Entwurfshinweise für planfreie Knotenpunkte an Straßen der Kategoriengruppe B,
RAS-K-2-B, Ausgabe 1995.
/22/
Aktuelle Hinweise zur Gestaltung planfreier Knotenpunkte außerhalb bebauter Gebiete, AH-RAL-K-2, Ausgabe 1993.
CadnaA - Reference Manual
Chapter 1 - Introduction
1.4 Literature
/23/
Schall 03, Richtlinie zur Berechnung der Schallimmissionen von Schienenwegen
(Guidelines for the Calculation of Sound Immission from Railways, in German), Akustik 03, Ausgabe 1990, Deutsche Bundesbahn, Bundesbahn-Zentralamt München
/24/
Aktuelle Information des BZA München - Akustik, Einfluss von Radabsorbern, 016,
103.10313, 962/6302, vom 19.4.1991
/25/
Aktuelle Information des BZA München - Akustik, Schall 03; Aerodyn. Einflüsse, 021,
103.10313, 962/6302 vom 17.8.1991
/26/
Verordnung zur Änderung der Sechzehnten Verordnung zur Durchführung des
Bundes-Immissionsschutzgesetzes (Verkehrslärmschutzverordnung - 16. BImSchV)
vom 18. Dezember 2014 (BGBl Teil I Nr. 61, S. 2269-2313 vom 23.12.2014).
/27/
AzB 1975 - Bekanntmachung der Datenerfassungssysteme für die Ermittlung von
Lärmschutzbereichen an zivilen (DES) und militärischen Flugplätzen (DES-MIL)
sowie einer Anleitung zur Berechnung, Der Bundesminister des Innern, GMBl. Ausg.
A, S.125, 1975
/28/
AzB 2008 - Verordnung über die Datenerfassung und das Berechnungsverfahren für
die Festsetzung von Lärmschutzbereichen vom 27. Dezember 2008 (BGBl. I S. 2980)
/29/
DIN 824 (1981-03): Technische Zeichnungen; Faltung auf Ablageformat (Technical
drawings - Folding to filing size, in German), Beuth Verlag, Berlin
/30/
DIN 18005, Teil 1 (1987-05) Schallschutz im Städtebau - Berechnungsverfahren (Noise
abatement in town planning - Calculation Methods, in German), Beuth Verlag, Berlin
/31/
DIN 18005, Teil 2 (9/91) Schallschutz im Städtebau, Lärmkarten - Kartenmäßige
Darstellung von Schallimmissionen (Noise abatement in town planning - Representation of noise levels on noise maps, in German), Beuth Verlag, Berlin
/32/
DIN 45684-1 (2006-09), Ermittlung von Fluggeräuschimmissionen an Landeplätzen,
Teil 1: Berechnungsverfahren (Calculation of Noise Contours at Landing Sites, in German), Beuth-Verlag, Berlin
/33/
DIN 45687 (2006-05), Akustik, Software-Erzeugnisse zur Berechnung der Geräuschimmission im Freien, Qualitätsanforderung und Prüfbestimmungen (Software-products for the calculation of noise outdoors, requirements and evaluation, in German),
Beuth-Verlag, Berlin
/34/
DIN 45691(2006-12), Geräuschkontingentierung (Noise Allotment, in German),
Beuth-Verlag, Berlin
/35/
DIN 52210, Bauakustische Prüfungen Luft- und Trittschalldämmung - Meßverfahren
/36/
VDI guideline 2058, Blatt 1, Beurteilung von Arbeitslärm in der Nachbarschaft
(Assessment of working noise in the vicinity, in German), Sept. 1985, Beuth-Verlag,
Berlin
/37/
VDI guideline 2571, Schallabstrahlung von Industriebauten (Sound radiation from
industrial buildings, in German), August 1976, Beuth-Verlag, Berlin
CadnaA - Reference Manual
1 15
1
16
1
1
Chapter 1 - Introduction
1.4 Literature
/38/
VDI guideline 2714, Schallausbreitung im Freien (Outdoor sound propagation, in German), August 1988 (withdrawn)
/39/
VDI guideline 2719, Schalldämmung von Fenstern und deren Zusatzeinrichtungen
(Sound Insulation by Windows, Ventilation devices etc., in German), August 1987,
Beuth-Verlag, Berlin
/40/
VDI guideline 2720 part 1, Schallschutz durch Abschirmung im Freien (Noise control
by barriers outdoors, in German), March 1997, Beuth-Verlag, Berlin
/41/
VDI guideline 3760, Berechnung und Messung der Schallausbreitung in Arbeitsräumen
(Calculation and measurement of sound propagation in workrooms, in German), Februar 1996, Beuth-Verlag, Berlin
/42/
VDI guideline 3770, Characteristic noise emission values of sound sources, Facilities
for recreational and sporting activities, April 2002, Beuth Verlag, Berlin
/43/
VDI guideline 3733 „Geräusche bei Rohrleitungen“ (Noise at Pipes), July 1996, Beuth
Verlag Berlin
/44/
VDI 3722, Effects of traffic noise, Part 2: Characteristic quantities in case of impact of
multiple sources, 05-2013, Beuth Verlag Berlin
/45/
Reinicke, W., J. Danner: Schallabstrahlung von Schornsteinen, Messung und technische
Möglichkeiten zu ihrer Minderung. UBA-Texte 17/1981, UBA-Forschungsbericht
105.03.301, Berlin, November 1981
/46/
VDI guideline 3945 part 3: Environmental meteorology - Atmospheric dispersion
models - Particle model, Ed.: Kommission Reinhaltung der Luft im VDI und DIN Normenausschuss KRdL, September 2000
/47/
TAL98 - Zur Bestimmung der meteorologischen Dämpfung - Eine Anleitung mit
Beispielen - Landesumweltamt NRW, Postfach 102363, D-45023 Essen
/48/
MLus 92, Ausgabe 96, Merkblatt über Luftverunreinigungen an Straßen - Teil: Straßen
ohne oder mit lockerer Randbebauung, Ausgabe 1991, Geänderte Fassung 1996, Forschungsgesellschaft für Straßen- und Verkehrswesen e.V., Köln, Arbeitsgruppe
Verkehrsführung und Verkehrssicherheit.
/49/
Parking Lot Study 1993, Ed.: Bayerisches Landesamt für Umweltschutz LfU (Bavarian
Environmental Agency), München 1993
/50/
Parking Lot Study 1995, Ed.: Bayerisches Landesamt für Umweltschutz LfU (Bavarian
Environmental Agency), November 1994
/51/
Parking Lot Study 2003, 4th edition, volume 89, Ed.: Bayerisches Landesamt für
Umweltschutz LfU (Bavarian Environmental Agency), Augsburg 8/2003
/52/
Parking Lot Study 2007, 6th edition, Ed.: Bayerisches Landesamt für Umwelt, Augsburg 2007.
CadnaA - Reference Manual
1 17
Chapter 1 - Introduction
1.4 Literature
/53/
ÖAL-Richtlinie 24, Blatt 1 und 2 (Ausgabe 2008-03-01): Lärmschutzzonen in der
Umgebung von Flughäfen, Planungs- und Berechnungsgrundlagen (Noise protection
zones in the vicinity of airports - planning and calculation, in German), Ed.: Österreichischer Arbeitsring für Lärmbekämpfung, Wien.
/54/
ÖAL-Richtlinie Nr. 28, Schallabstrahlung und Schallausbreitung (Sound Radiation and
Sound Propagation, in German), Dezember 1987, & Erläuterende Ergänzung, Februar
2001, Ed.: Österreichischer Arbeitsring für Lärmbekämpfung, Wien
/55/
Ergänzung zur ÖAL-Richtlinie Nr. 28, (Amendment to ÖAL guideline 28) Februar
2001, Hrsg.: Österreichischer Arbeitsring für Lärmbekämpfung, Wien.
/56/
ÖNORM ISO 9613-2:2008, Akustik, Dämpfung des Schalls bei der Ausbreitung im
Freien,
Teil 1 (1993-06): Berechnung der Schallabsorption durch die Luft,
Teil 2 (1996-12): Allgemeines Berechnungsverfahren,
Beuth Verlag Berlin.
/57/
ONR 305011:2004-09-01, Berechnung der Schallimmission durch Schienenverkehr Zugverkehr, Verschub- und Umschlagbetrieb (Noise immission by railway traffic, in
German).
/58/
ONR 305011:2009-11-15, Berechnung der Schallimmission durch Schienenverkehr Zugverkehr, Verschub- und Umschlagbetrieb (Noise immission by railway traffic, in
German).
/59/
RVS 3.02 Lärmschutz (Dezember 1997), Ed.: Forschungsgesellschaft für das Verkehrund Straßenwesen (FVS) Wien.
/60/
RVS 04.02.11 Lärmschutz (März 2006), Ed.: Forschungsgesellschaft für das Verkehrund Straßenwesen (FVS) Wien.
/61/
Amendment for RVS 04.02.11 Lärmschutz, edition March 2006 (April 2008), Ed.: Forschungsgesellschaft für das Verkehr- und Straßenwesen (FVS) Wien.
/62/
forum Schall: Anleitung für die Modellbildung zur Schallimmissionsprognose nach
NORM ISO 9613-2:2008 und ÖNORM EN 12354-4:2001-02-01, Hrsg.: Umweltbundesamt/Lebensministerium, Wien 2011
/63/
Schriftenreihe Umweltschutz Nr. 57: Anleitung zur Ermittlung und Beurteilung von
Lärmimmissionen an Strassen, Ed.: Bundesamt für Umweltschutz, Bern, Januar 1987.
/64/
Schriftenreihe Umweltschutz Nr. 60: Computermodell zur Berechnung von Strassenlärm, Teil 1: Bedienungsanleitung zum Computerprogramm StL-86, Ed.: Bundesamt
für Umweltschutz, Bern, März 1987.
/65/
Mitteilung zur Lärmschutz-Verordnung (LSV) Nr. 6 (1995): Strassenlärm: Korrekturen
zum Strassenlärm-Berechnungsmodell, Bundesamt für Umwelt, Wald und Landschaft,
Bern.
CadnaA - Reference Manual
Austria
Switzerland
1
18
1
1
Scandinavia
France
Chapter 1 - Introduction
1.4 Literature
/66/
SN 640 578:2006-07, Lärmimmissionen von Parkierungsanlagen - Berechnung der
Immissionen.
/67/
Leitfaden Strassenlärm. Vollzugshilfe für die Sanierung. Stand: Dezember 2006,
Umwelt-Vollzug Nr. 0637, Bundesamt für Umwelt BAFU und vom Bundesamt für
Strassen ASTRA Bern, 2006.
/68/
Schriftenreihe Umweltschutz Nr. 116: SEMIBEL, Version 1, Schweizerisches Emissions- und Immissionsmodell für die Berechnung von Eisenbahnlärm, Ed.: Bundesamt
für Umwelt, Wald und Landschaft, Bern, März 1990.
/69/
Schriftenreihe Umwelt Nr. 301, Lärm: Wirtschaftliche Tragbarkeit und Verhältnismässigkeit von Lärmschutzmassnahmen; Bundesamt für Umwelt, Wald und Landschaft
(BUWAL) Bern, 1998.
/70/
Schriftenreihe Umwelt ; Nr. 366, Lärm: SonRoad - Berechnungsmodell für Strassenlärm, Ed. vom Bundesamt für Umwelt, Wald und Landschaft BUWAL; Bern, BUWAL,
2004.
/71/
Environmental noise from industrial plants - General prediction method. Danish
Acoustical Laboratory, The Danish Academy of Technical Sciences, Report no. 32,
1982.
/72/
Railway Traffic Noise - The Nordic Prediction Method, TemaNord 1996:524, Nordic
Council of Ministers, Store Strandstraede 18, DK-1255 Copenhagen K, ISBN 92
9120837 X, ISSN 0908-6692.
/73/
Road Traffic Noise - Nordic Prediction Method, TemaNord 1996:525, Nordic Council
of Ministers, Store Strandstraede 18, DK-1255 Copenhagen K, ISBN 92 91208361,
ISSN 0908-6692.
/74/
Rapport 6241: „Ljud från vindkraftverk“, Ed.: Naturvårdsverket, Stockholm, Dec.
2001, ISBN 91-620-6241-7.
/75/
User’s Guide Nord2000 Road, Editors: Delta, SINTEF, SP, VTT, Document reference
AV 1171/06, Hørsholm/DK, May 2006
/76/
Förordning (2015:216) om trafikbuller vid bostadsbyggnader, Svensk författningssamling 2015:216
/77/
NMPB-Routes 96 - Bruit des Infrastructures Routières, méthode de calcul incluant les
effets météorologiques, Ed.: Ministère de l’Équipement, du Logement, des Transports
er du Tourisme/CERTU/SETRA/LCPC/CSTB, Janvier 1997 (ISBN 2-11-089201-3).
/78/
NMPB-Routes-2008 - Methodological guide, Road noise prediction, volume 2: NMPB
2008 - Noise propagation computation including meteorological effects, Ed.: SETRA
(Service d'études sur les transports, les routes et leurs aménagements), April 2009
(Référence : LRS 2008-76-069).
CadnaA - Reference Manual
1 19
Chapter 1 - Introduction
1.4 Literature
/79/
NMPB-Routes-2008 - Guide méthodologique, Prévision du bruit routier, Volume 1:
Calcul des émissions sonores dues au trafic routier, Ed.: SETRA (Service d'études sur
les transports, les routes et leurs aménagements), April 2009 (Référence Sétra: 0924-1).
/80/
NF S 31-133 (February 2011), Acoustics, Outdoor noise, Calculation of sound levels
(F: Acoustique, Bruit dans l'environnement, Calcul de niveaux sonores), Association
Française de Normalisation (AFNOR), www.afnor.org
/81/
Department of Transport, Welsh Office: Calculation of Road Traffic Noise (CRTN),
published by: HMSO, London, 1988.
/82/
The Department of Transport: Calculation of Railway Noise (CRN), published by:
HMSO, London, 1995.
/83/
TRL Limited: Converting the UK traffic noise index LA10,18h to EU noise indices for
noise mapping, authors: P G Abbott, P M Nelson, Report PR/SE/451/02 [EPG 1/2/
37]
/84/
BS 5228-1:2009 - Code of practice for noise and vibration control on construction and
open sites, Part 1: Noise , Ed.: BSI British Standards 2008.
/85/
The Highways Agency et al.: Design Manual for Roads and Bridges (DRMB), HA 213/
08, volume 11 environmental assessment, section 3 environmental assessment techniques, August 2008.
/86/
Additional railway noise source terms for “Calculation of Railway Noise 1995”, report
produced for Defra by AEAT, published by the Department for Environment, Food
and Rural Affairs, January 2007.
/87/
SRM II - Reken- en Meetvorschriften Railverkeerslawaai ‚96, Publikatiereeks Verstoring, Nr. 14/1997, VROM, november 1996
/88/
Miedema: TNO Built Environment und Geosciences, Environement & HEALTH
draft TNO report 2005-007 "Rating environmental noise on the basis of noise maps";
Miedema, Henk M.E.; Borst, Hieronymus E., City: Delft; No. 05 6N 013 64041
/89/
TNM - FHWA Federal Highway Administration Model (http://www.trafficnoisemodel.org) TNM Version 2.5, McTrans Center University of Florida, 2088 Northeast
Waldo Road, Gainesville, Fl 32609, http://mctrans.ce.ufl.edu
/90/
FHWA Traffic Noise Model, Version 1.0, Technical Manual, Final Report, February
1998, Ed.: U.S. Department of Transportation, Federal Highway Administration,
FHWA-PD-96-010, DOT-VNTSC-FHWA-98-2
/91/
FTA-report: Transit Noise and Vibration Impact Assessment", Ed.: Office of Planning
and Environment, Federal Transit Administration, FTA-VA-90-1003-06, May 2006
(published by Office of Planning and Environment, Federal Transit Administration)
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United Kingdom (UK)
The Netherlands
USA
20
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1
China
Chapter 1 - Introduction
1.4 Literature
/92/
FRA-report: High-Speed Ground Transportation Noise and Vibration Impact Assessment, HMMH Report No. 293630-4, October 2005 (published by US Department of
Transportation, Federal Road Administration)
/93/
China State Environmental Protection Standard HJ2.4-2009 (Replacement of HJ/T2.41995): Technical Guidelines for Noise lmpact Assessment, Release on 2009-12-23
implement on 2010-04-01, Released by Ministry of Environmental Protection
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Chapter 1 - Introduction
1.4 Literature
Articles & Reports
/94/
Heutschi, K.: SonRoad - Berechnungsmodell für Strassenlärm, Ed.: Bundesamt für
Umwelt, Wald und Landschaft BUWAL, Bern, 2004 (Schriftenreihe Umwelt Nr. 366)
/95/
Kozak, J., Liberko, M.: Updated Method for Calculation of Road Traffic Noise (in
Czech), Annex of the Newsletter of the Ministry of the Environment of the Czech
Republic. 1996, No. 3, p.1-16
/96/
Kuttruff, H.: Über Nachhall in Medien mit unregelmäßig verteilten Streuzentren, insbesondere in Hallräumen mit aufgehängten Streukörpern“,Acustica 18 , 1967
/97/
Probst, W.; Donner, U.: Die Unsicherheit des Beurteilungspegels bei der Immissionsprognose (The uncertainty of the sound pressure levels in noise prediction, in German), ZfL 3/2002 Mai, Springer-VDI-Verlag GmbH & Co. KG, Düsseldorf.
/98/
Probst, W.: Geräuschentwicklung von Sportanlagen und deren Quantifizierung für
Immissionsschutztechnische Prognosen (Noise emission from sports facilities and their
quantification with regard to immission prognosis, in German), Bundesinstitut für
Sportwissenschaft, Köln, 1994 - Schriftenreihe Sportanlagen und Sportgeräte, B94.2 ISBN 3-921896-84-3
/99/
Probst, W.: „Lärmkontingentierung mit Rechnerunterstützung“ (Computer Aided
Noise Allotment, in German), Vortrag bei der Informationsveranstaltung über Qualitätssicherung von Softwareprogrammen, München
/100/
Probst, W.: Schallabstrahlung und Schallausbreitung - Berechnungsmodelle und Schallleistungsbestimmung, Forschungsbericht Fb. 556 der Bundesanstalt für Arbeitsschutz,
Dortmund 1988
/101/
Probst, W., Neugebauer G., Kurze U., Jovicic S. und Stephenson U.: Schallausbreitung
in Arbeitsräumen, Forschungsbericht Fb 621 der Bundesanstalt für Arbeitsschutz,
Dortmund 1990
/102/
Probst, W.; Huber, B.: Schallstrahlen und Reflexionen bei der Berechnung der Schallausbreitung mit numerischen Verfahren (Sound Rays and Reflections when calculating
Sound Propagation using Numercial Methods, in German), Zeitschrift für Lärmbekämpfung ZfL 44/1997, 143-149
/103/
Probst, W.; Huber, B.: Die Berechnung der Schallemission von Parkhäusern (Calculation of Noise Emission by Multi-Storey Car Parks, in German), Zfl 5/2000, 47. Jhrg.
Seite 175
/104/
Probst, W.: Calculation of Noise Levels in an Environment with highly reflecting
Objects and Surfaces, Euronoise 1998, München
/105/
Probst, W.; Huber B.: Modellierung von Kaminen und akustisch teildurchlässigen Anlagen (Modeling chimneys and acoustically transparent plants, in German), ZfL 49
(2002), No. 4, 144-147, Springer-VDI-Verlag GmbH & Co. KG, Düsseldorf
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Chapter 1 - Introduction
1.4 Literature
/106/
Probst. W.: Checking of Sound Emission Values, Report Fb 851. Schriftenreihe der
Bundesanstalt für Arbeitsschutz, und Arbeitsmedizin, Dortmund/Berlin 1999
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Chapter 1 - Introduction
1.4 Literature
Legal Acts
/107/
Achtzehnte Verordnung zur Durchführung des Bundes-Immissionsschutzgesetzes
(Sportanlagenlärmschutzverordnung - 18. BImSchV) vom 18. Juli 1991, Bundesgesetzblatt, Jahrgang 1991, Teil 1, S. 1588
/108/
Sechzehnte Verordnung zur Durchführung des Bundes-Immissionsschutzgesetzes
(Verkehrslärmschutzverordnung - 16.BImSchV) vom 12.6.1990. BGBL. IS.1036
/109/
TALärm - Technische Anleitung zum Schutz gegen Lärm, Sechste Allgemeine Verwaltungsvorschrift zum Bundesimmissionsschutzgesetz, 26.8.1998, Gemeinsames Ministerialblatt vom 28.8.1998
/110/
TA-Luft 2002: Erste Allgemeine Verwaltungsvorschrift zum Bundes-Immissionsschutzgesetz (Technische Anleitung zur Reinhaltung der Luft - TA Luft) Vom 24. Juli
2002 (GMBl. 2002, Heft 25 - 29, S. 511 - 605)
/111/
23. BImSchV - Dreiundzwanzigste Verordnung zur Durchführung des Bundes-Immissionsschutzgesetzes (Verordnung über die Festlegung von Konzentrationswerten) vom
16. Dezember 1996 (BGBl. 1 S. 1962)
/112/
22. BImSchV: 22. Verordnung zur Durchführung des Bundesimmissionsschutzgesetzes, 11.September 2002 BGBlI2002, 3626
/113/
VBEB Vorläufige Berechnungsmethode zur Ermittlung der Belastetenzahlen durch
Umgebungslärm (German Interim calculation method for the calculation of people
annoyed, in German), Stand 28.6.2006 - Entwurf
/114/
003/613/EC: COMMISSION RECOMMENDATION of 6 August 2003 concerning
the guidelines on the revised interim computation methods for industrial noise, aircraft
noise, road traffic noise and railway noise, and related emission data (notified under
document number C(2003) 2807)
/115/
Vorläufige Berechnungsmethode für den Umgebungslärm an Straßen (VBUS, German
interim calculation method for road noise, in German), Bundesanzeiger, Jahrgang 58,
Nr. 154a vom 17. August 2006
/116/
Vorläufige Berechnungsmethode für den Umgebungslärm an Schienenwegen
(VBUSch, German interim calculation method for railway noise, in German), Bundesanzeiger, Jahrgang 58, Nr. 154a vom 17. August 2006
/117/
Vorläufige Berechnungsmethode für den Umgebungslärm durch Industrie und Gewerbe (VBUI, German interim calculation method for industrial noise, in German),
Bundesanzeiger, Jahrgang 58, Nr. 154a vom 17. August 2006
/118/
Vierundzwanzigste Verordnung zur Durchführung des Bundes-Immissionsschutzgesetzes (Verkehrswege-Schallschutzmaßnahmenverordnung - 24.BImSchV, Bundesgesetzblatt Jahrgang 1997 Teil I Nr. 8, ausgegeben zu Bonn am 12.2.1997
/119/
Magnetschwebebahn-Lärmschutzverordnung vom 23.9.1997 (BGBl. 2329, 2338)
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1.4 Literature
/120/
ZTV-Lsw88: Zusätzliche Technische Vorschriften und Richtlinien für die Ausführung
von Lärmschutzwänden an Straßen, Verkehrsblatt - Dokument Nr. B 6508 - Vers. 88.2,
Der Bundesminister für Verkehr, Abteilung Straßenbau, Verkehrsblatt-Verlag Borgmann GmbH & Co KG, Hohe Straße 39, Hohe Str. 39, 44139 Dortmund
/121/
Directive 2002/49/EC of the European Parliament and of the Council of 25th June
2002 relating to the assessment and management of environmental noise, Official Journal of the European Communities, L189/12, EN, 18.7.2002
/122/
Bundesumgebungslärmverordnung - Bundes-LärmV, Jahrgang 2006, ausgeg. 5.April
2006, Bundesgesetzblatt für die Republik Österreich.
/123/
Länderausschuss für Immissionsschutz (LAI): Dokumentation zur Schallausbreitung,
Interimsverfahren zur Prognose der Geräuschimmissionen von Windkraftanlagen, Fassung 2015-05.1.
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Chapter 2 - Sound Sources
Chapter 2 - Sound Sources
2
Sound sources, the emission of which is described based on the sound power
level are called "general sources". In CadnaA, the emission of general
sources (such as point, line, and area sources) can be described by single
number ratings (sound power level PWL in dB(A)) or by spectra (linear, or
with A-, B-, C- or D-weighting) and for the three time periods Day/Evening/Night separately. When both emission types are present within a project, both are included in the calculation at the same time. Within a spectral
calculation the sound pressure level or any other evaluation parameter (see
chapter 6.2.5) at the receiver point is calculated as a spectrum (linear or A-, B, C- or D-weighted) and as a sum level in dB(A).
General Sources
Spectra are entered in the local or global libraries (see chapter 12.1), and are
referred to in the edit dialog of the source by entering their ID (see manual
„Introduction to CadnaA“).
The emission parameter of „parametric sources“ is not the sound power
level, but several source type specific parameters. For example, the following
sources are parametric sources:
•
•
•
•
•
road (see chapter 2.4)
railway (see chapter 2.6)
parking lot (see chapter 2.7)
crossing with traffic lights (see chapter 2.5)
tennis point of service (see chapter 2.3)
Those source types require to specify an emission parameter which is specific
to the standard/guideline or, for example the overall traffic count, the percentage of heavy vehicles, the type of road surface, and the traffic speed
where the emission parameter is calculated from.
The input figures can be specified for the three time periods Day/Evening/
Night even when the selected standard just provides only one or two time periods.
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Parametric Sources
2
2
Chapter 2 - Sound Sources
The input of objects is explained in the manual „Introduction to CadnaA“.
2
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23
Chapter 2 - Sound Sources
2.1 Industrial Sources
2.1
Industrial Sources
The general source types, such as point, line and area sources (horizontal and
vertical), are used to model a variety of noise sources including also the building radiation. Moreover, they may have an individual directivity (see chapter
2.2).
2
When applying these sources to mode the sound radiation from buildings the
object snap is activated in order to place them in front of the building’s facade at a distinct distance (see chapter 9.3). This prevents from the source being placed inside the building.
see chapter 2.1.1 "Common Input Data" for detailed information on the
common parameters of the general sound sources.
A point source is entered at the position of the mouse pointer with a mouse
click at the desired location. The point source is represented by a cross.
Point Source
Point sources are noise sources whose dimensions are small in comparison to
the distance to the receiver points. Examples are ventilation openings,
pumps, motors, and people shouting.
Line sources are modelled as open polygons. Line sources have one
dimension only, while the dimensions in the other two orthogonal
dimensions are small compared with the distance to the receiver points. Examples are pipelines, conveyor belts, and traffic routes on a factory site.
Line Source
Upon calculation, CadnaA subdivides the line source in a two-step
procedure. First, the line source is subdivided into sections being screened
and sections not being screened by any obstacles lying between the receiver
and the sub-source (see chapter 6.1.3 "Projection at extended Sound Sources"). In a second step, the distance between the receiver and each section is
determined and a further subdivision is required if the section length exceeds
the minimum distance criterion.
Area sources are modelled as closed polygons. They are noise sources
extending in two dimensions while the third dimension perpendicular to its
area is small in relation to the receiver distance.
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Area Source
4
2
Chapter 2 - Sound Sources
2.1 Industrial Sources
CadnaA subdivides upon calculation the area sources into sufficiently small
sub-areas. In the centre of each sub-source a point source with the appropriate partial sound power is placed. This procedure results in a fine grid of
point sources, the total emission of which represents the area source.
2
horizontal Area Source
Horizontal area sources are inserted by entering their horizontal projection.
Examples of area sources are parking lots (see chapter 2.7), sports facilities,
and even entire industrial or commercial areas.
vertical Area Source
Vertical area sources are inserted by entering their horizontal projection as an
open polygon line.
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Chapter 2 - Sound Sources
2.1 Industrial Sources
Upon calculation, CadnaA subdivides the area source in a two-step
procedure. First, the area source is subdivided into partial areas being
screened and partial areas not being screened by any obstacle lying between
the receiver and the source (see chapter 6.1.3 "Projection at extended Sound
Sources"). Then, in the second step, the distance between the receiver point
and each partial area is determined and a further subdivision is required if the
largest dimension of a partial area exceeds the minimum distance criterion.
Geometric definition of the vertical area source
In order to enter a window (as illustrated above) as a sound-radiating area,
enter a vertical area source as a polygon line in xy-plane at a short distance in
front of the facade. For a clear distinction, a distance of approximately 0.05 m
is used. This distance is automatically set via the dialog Object Snap
(Options menu) prior to the input of the vertical area source (see chapter 9.3
"Object Snap").
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2
Chapter 2 - Sound Sources
2.1 Industrial Sources
2
Building
Vertical area source
Vertical area source in front of a facade
On the edit dialog of the vertical area source specify the position of the top
edge via button Geometry. As with any other object, this height may be
defined as relative or absolute value, or with respect to the roof of a building.
The latter is particularly convenient when entering e.g. ventilators placed onto
a roof. The lower edge of the vertical area is specified as „z-dimension“
downwards from the top edge. More complicated outlines of vertical soundradiating areas can be approximated by several rectangular areas.
Upon calculation, the vertical area source is replaced by a series of line
sources with a spacing of 1 m. These are subdivided into sections as
described above.

The subsequent chapters are specific for each standard or guideline
available in CadnaA. These specifications do not represent a copy of
the standardized procedures, rather the way they are implemented.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
2.1.1
Common Input Data
On the dialogs Point Source, Line Source, Area Source and vertical Area
Source the following values and settings govern the resulting sound power
level:
•
•
•
•
•
•
•
•
2
Type (Single Band, Spectrum or SET-S module)
Frequency (Hz)
Correction (dB)
type of emission:
PWL: at point, line, area sources and
PWL’: at line sources
PWL’’: at area sources
PWL-Pt: at line and area sources
TransLoss (dB)
Attenuation (dB)
Area (m²)
normalized A (dBA)
as well as the input or settings for operating time („Source in Steady-State“,
„Operating Time (min)“). The resulting sound power level is calculated from
these parameters and displayed for the time periods Day/Evening/Night
(Result. PWL“).
From the list box „Type“ the following options can be selected:
•
•
•
Type
Single band,
Spectrum or
a pre-defined SET-S module (see chapter 12.2).
The options „Single band“ and „Spectrum“ require the input of acoustical
data determining the resulting sound power level. In contrary, the selection of
an SET-S module prompts to specify the physical parameters of the
respective type of source in a sub-table (e.g. flow rate in m³/s, nominal
capacity in kW). From these parameters the sound power level spectrum is
calculated.
By using the attribute FREQ the dominant frequency can be changed. Use
the space key or a blank to toggle to type „Spectrum“.
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Toggling the Type per
Attribute
8
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
Single band / Frequency
(Hz)
With selection „Single band“ the sound power level entered under PWL,
PWL’, PWL’’, or PWL-Pt is considered as the A-weighted total level. In this
case, for frequency dependent propagation parameters (e.g. air absorption)
the resulting values is calculated for the frequency specified. Default frequency value is 500 Hz (see ISO 9613-2, section 1 /8/).
Spectrum
With selection „Spectrum“ the sound power level entered under PWL, PWL’,
PWL’’, or PWL-Pt is considered as A-weighted level per octave band. In this
case, the displayed sound power level PWL („Result. PWL“ in dB(A)) results
from adding 10 lg 9 = 9,5 dB for 9 octaves.
2
Alternatively - and this is the common procedure in conjunction with using
spectra - instead of a figure an ID-code of the respective spectrum is entered
or selected.
Example for „Spectrum“
•
Enter the local library (see Chapter 12 - Libraries) via Tables|
Libraries (local)|Sound Levels the following sound power spectra:
•
On the point source’s dialog select for „Type“ the option „Spectrum“ for
spectral calculation.
•
Enter the ID-code „SP_001“ of compressor 1 into the box PWL. This
refers to that spectrum.
•
The text sequence SP_001 may either be entered via the keyboard or be
selected from the local library by clicking the file selector symbol,
subsequently selecting the first data set and clicking OK.

Access to the global libraries occurs by clicking the file selector symbol
while holding the SHIFT-key depressed.

Upon selection of a spectrum from the global library the data set is
copied automatically to the local library.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
In this example, after having selected the compressor spectrum the resulting
A-weighted sound power level (Result. PWL) and the spectrum shape are displayed, the latter in the lower right corner of the dialog Point Source.
Dialog Point Source with referencing to spectrum-ID SP_001
•
Now, upon clicking again to the file selector symbol and selecting a different spectrum, the former reference will be replaced by the new one.
In case a second spectrum should be added energetically to the first one, considering the rules of level summation, press the CTRL-key prior to selection
of the second spectrum. This causes the second spectrum to be entered with
the operator ++ in front being the symbol for energetic level summation (for
further operators see the CadnaA-manual „Attributes, Variables, and Keywords“, chapter "Chapter 5 - Operators & Functions").
This summation formula can also be entered via the keyboard. During typing
the red text indicates that the formula is not complete or cannot be evaluated,
respectively.

Formulas in the input box „PWL“ are restricted to 15 characters.
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2
10
2
local SET-S modules
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
The SET-S modules from the local SET-S library are listed here. Upon selection of a module and input of the respective parameters a..j on the sub-table
the resulting spectrum and the A-weighted total level „Result. PWL“ is displayed.
Example: SET-S module „Radial Roof Ventilator“ selected
Sound power of roof ventilator after specifying its parameters
A total overview of all SET-S modules delivered with CadnaA see chapter
12.2 "SET-S".
Attributes
Via the attributes SET_ID and SET_PARM_A to _J an SET-S module can
be selected and its parameters be defined (see chapter 1.1 in the CadnaA
manual „Attributes, Variables, and Keywords“.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
The spectrum monitor at the bottom right corner of the source dialog
displays the frequency spectrum in from of bars. Clicking the diagram cycles
among no weighting (i.e. linear) and A-, B-, C- or D-weighting. With this
switching the emission of the source remains.
Spectrum Monitor
Depending on the source type the emission can be specific for the following
„types“ of sound power levels (attribute „LWTYP“):
PWL-Type
•
with point sources: by the sound power level PWL in dB(A),
Dialog Point Source
•
with line sources: by the sound power level PWL in dB(A), by the sound
power level per unit length PWL’ in dB(A), or by the sound power level
PWL-Pt of a moving point source (default setting: PWL'),
Dialog Line Source with list box „LWTYP“ opened
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12
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
•
2
with area sources: by the sound power level PWL in dB(A), by the sound
power level per unit area PWL’’ in dB(A), or by the sound power level
PWL-Pt of a moving point source (default setting: PWL’’).
Dialog Area Source (horizontal) with list box „LWTYP“ opened
The input box to the right of the list box for the emission type (attribute LWTYP) may contain a single number, a reference to a spectrum, or a combination of both, or even an equation.
Result. PWL
When the sound power level per unit length PWL, is entered for a line source
or the sound power level per unit area PWL’’ is entered for an area source,
the total sound power level resulting from the dimensions of that source is
displayed here (excluding the correction for operating time and the directivity
index K0/D). This sound power level is used as the emission characteristic
of the source within the calculation of sound propagation.
As the height of the terrain at the polygon points of the source is not known
when the values are entered, this total sound power level refers, with relative
heights, to the horizontal projection of the source. Consequently, this will not
be correct for inclined line or area sources. Upon calculation, however, the
absolute heights at the polygon points is updated and the correct total sound
power level is determined.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
When entering the sound power level per unit length or unit area for inclined
line or area sources, the heights of which are given as relative coordinates, the
total value displayed for „Result PWL“ is not yet correct as the increased radiating area due to the inclination of the source is not considered so far.
However, this will the case when the dialog is closed and reopened.
Inclined Sources
2
Example: inclined area
source
Plane area source and inclined area source (by 45 degrees),
both having the same 2D-ground plane
Resulting sound power level of a plane area source (left) and of a
by 45° inclined area source (right), both having the same 2D-ground plane
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2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
Correction
To consider different emissions for the time periods Day, Evening, and Night
specify a correction for each of these periods. The correction entered will be
added to the sound power level.
Attenuation
Via the „Attenuation“ box a value can be entered which will be considered as
an additional damping of the source’s emission. Furthermore, attenuation
spectra from the local and global libraries can be referenced. The entered or
referenced attenuation will be subtracted from the sound power level.
Example
After the compressor (with PWL=104 dB(A)) of the recent example a
silencer with an additional attenuation of 8 dB is installed.
2
Dialog Point Source with an attenuation of 8 dB
•
Using Equations
Enter in box „Attenuation“ the figure 8, resulting in a sound power level
(„Result. PWL“) of 96 dB(A).
The attenuation input box may also receive complex formulas or the ID of a
spectrum.

Formulas for „Attenuation“ are restricted to 63 characters.

While the „Attenuation“ value is directly subtracted from the PWL, the
resulting PWL when specifying „TransLoss“ - in conjunction with the
interior sound pressure level („interior level“) - considers also an area
and a diffuse-to-free-field correction (see below).
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
2 15
For example, several attenuations may attenuate the sound power radiated
(e.g. pipe elbows, changes in cross section, fittings, and silencers). This sum
of attenuations may be described by, e.g.: 8+4+3.5+2.
2
Of course, the total attenuation could be entered by a single figure directly,
but the specification as a sum illustrates more obviously the individual
attenuations contributing and also will be listed in the respective column of
the source table. The line offers to enter even more complex formulas, such
as: ((8+4+3.5+2)++23)-19.
As described for other input boxes, ++ stands for the energy-equivalent (or
level) addition, and -- for the level subtraction (see also CadnaA-manual „Attributes, Variables, and Keywords“, see chapter "Chapter 5 - Operators &
Functions").
Furthermore, arbitrary damping spectra from the local or global library (see
Chapter 12 - Libraries) can be referenced via the input box „Attenuation“.
In the subsequent figure, the attenuation spectra of two changes in cross section and a silencer are combined at a line source modeling a pipe section:
Combined attenuations on dialog Line Source
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Referencing Attenuations
16
2
2
Sound Power of a
moving Point Source
PWL-Pt
Chapter 2 - Sound Sources
2.1.1 Common Input Data
The line or the horizontal area source may be used to model the emission of
a moving point source (emission type option: PWL-Pt).
When using a line source, the sound power level of the point source, the
number of events per hour Q (number of pass-bys) and the speed (in km/h)
have to be specified. The resulting sound power level PWL and the sound
power level per unit length PWL’ calculate from:
PWL  PWLPt  10 lg
Q
l
v
 10 lg
 10 lg
 30 dB
(h 1 )
( m)
(km / h)
PWL '  PWLPt  10 lg
Q
v
 10 lg
 30 dB
1
(h )
(km / h)
With area sources, the sound power level of the point source and the number
of events Q are required. The resulting sound power level PWL and the
sound power level per unit area PWL’’ calculate from:
PWL  PWLPt  10 lg
Q
(h 1 )
PWL ' '  PWLPt  10 lg
Q
S
 10 lg 2
1
(h )
(m )
Example
see manual „Introduction to CadnaA“, chapter 6.2 "Internal Driveways and
Areas"
normalized A
With this check box „normal. A“ activated and a number entered, a constant
K in dB is subtracted from or added to the frequency-band levels resulting
from the specified PWL in order to obtain this value for the total A-weighted
sound power level. This option enables the application of normalized spectra
(with a total sum level of 0 dB) the final emission value of which is specified
be entering the respective value in input box „norm. A“.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
All types of general sources described above can be applied to model the
sound radiation from buildings. In order to specify the radiated sound power
based on the (diffuse) interior level SPL activate the option „TransLoss“.
Subsequently, the emission type (Lw-type) switches to „Interior Level“.
Enter an interior level and in the box „TransLoss“ a single number rating
(weighted sound reduction index Rw or STC) or the ID-code of a sound
reduction index spectrum. All techniques for the selection of spectra from
the libraries and the handling of user-defined formulas apply as before.

Formulas in the input box „TransLoss“ are restricted to 15 characters.
Dialog vertical Area Source (radiating area S=100 m²),
Transmission Loss specified by a single number rating
The resulting sound power level PWL calculates in CadnaA from (S0=1 m²):
•
for spectral sources (S0=1 m2):
LwA  LpA  R f   6 dB  10 lg
•
S
S0
for sources based on the A-weighted sound power level (S0=1 m²):
LwA  LpA  Rw  4 dB  10 lg
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S0
Transmission Loss
2
18
2
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
The calculation for single number ratings follows the VDI guideline 2571
(edition 8.1976 /37/) assuming RA = Rw + C = Rw - 2 dB (with the spectrum
adaptation term C according to ISO 717-1 /10/). In general, a spectrum
adaptation term C=-2 dB is obtained for heavy monolithic walls and floors
only. For lightweight building structures the spectrum adaptation term C can
be lower, e.g. down to C=-6 dB.

The informative annex B of the European Standard EN 12354-4 lists
the diffusity correction Cd depending on the type of room:
Type of Room
Cd (dB)
relatively small, uniformly shaped rooms (diffuse field),
reflecting walls (REMARK: as applied by VDI)
-6
relatively small, uniformly shaped rooms (diffuse field),
absorbing walls
-3
large flat or long halls, many sources (average industrial building),
reflecting walls
-5
industrial building, few dominating directional sources,
reflecting walls
-3
industrial building, few dominating directional sources,
absorbing walls
0
When the option „TransLoss“ is activated and the transmission loss is zero a
value of zero has to be entered. With this box being empty no radiated sound
power results.
Additionally, with point and area sources an area (m²) has to be entered in the
respective box as this value is not available from the object’s geometry data
(see the subsequent section).
CadnaA - Reference Manual
Chapter 2 - Sound Sources
2.1.1 Common Input Data
•
Select for the sound insulation of the facade in the previous example the
spectrum „steel sheet with trapezoidal corrugations 45 mm“ from the
global library (menu Tables|Libraries (global)|Sound Reduction (ID:
R26).
•
To this end, click on dialog vertical Area Source with the SHIFT-key
depressed on the file selector symbol to the right of the input box
„TransLoss“.
•
Select the spectrum with ID „R26“ and click OK.
•
Switch the emission type from „Single band“ to „Spectrum“.
The sound power level and its spectrum as resulting from the input data is
displayed.
Dialog vertical Area Source (radiating area S=100 m²),
Transmission Loss specified by referencing a sound reduction spectrum
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Example for spectral
Sound Reduction Index
2
20
2
Area (m²)
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
With point and line sources a radiating area has to specified when modelling
sound radiation based on the indoor level. To this end, click the check box,
and enter the relevant area. With horizontal or vertical area sources are
respective value is required just when the actual radiating area differs from
the geometrical area of the area source.

Example
For horizontal and vertical area sources, the difference between the
sound power level PWL and the sound power level per unit area PWL’’
is still determined - as before - from the entered geometry, since the
entire source radiates as drawn.
The sound radiation from a glazed facade within a heavy outer wall is
modelled by a vertical area source in front of the entire wall. In order to
ignore the radiation from the heavy parts of the facade just the area of the actual glass facade is entered.
When the option „Area (m²)“ is not activated, CadnaA considers the entire
area source as derived from the object’s geometry in the calculation.

Check for the value of „Result. PWL“. As long as it is zero, parameters
are still missing, for instance, with calculations based on the indoor level
either the area or the sound reduction index/TL.
The length (m) of the line source and the area of the area source (m²) can be
checked via the dialog Geometry. For a vertical area source - drawn from two
polygon points - this value is zero as this area entered refers to the horizontal
projection (2D-area). Instead, the area of vertical area sources can be seen
after a calculation in the box „Area (m²)“ on the edit dialog.
The length of a line-like object can be specified in an exact way (see manual
„Introduction to CadnaA“, context menu command „Specify Length“). and
chapter 3.1.6 "Generate Building" in this manual.
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
By default, the option „Source in Steady-State“ is selected where no
correction for operating time applies. In this case, the specified noise
emission is constant for each entire daily period (see chapter 6.2.4).
Source in SteadyState / Operating
Time (min)
By selecting the option „Operating Time (min)“, the source-specific
operating time in minutes can be entered for each daily period
„Day|Recreation (=Evening)|Night“. The correction for operating time
result from the operating times and the reference time intervals D|E|N
specified in the configuration of calculation (see chapter 6.2.4) and calculates
from:
10lg
Toperating time
Treference time
 dB
Furthermore, diurnal patterns (= hourly emission profile covering 24 hours)
can be used for industrial sources in CadnaA. To this end, first define a diurnal pattern in the local or global library „Diurnal Patterns“ (see chapter 12.3).
Subsequently, this diurnal pattern can be selected from the list box.
Point source with selected diurnal pattern TG_01
Diurnal patterns may also get assigned using the attribute TEINW_GANG
(see chapter 1.1 in the manual „Attributes, Variables, and Keywords“).
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Addressing Diurnal
Patterns
2
22
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data

2
Example 1
When using diurnal patterns describing the additional evaluation
parameter „loudest hourly level per time period D/E/N“ (L1hMaxD,
L1hMaxE, L1hMaxN) are available on tab „Evaluation Parameter“ (see
chapter 6.2.5).
The receiver level of a point source without correction for operating time is
35 dB(A). Then, the following diurnal pattern TG_01 is selected:
Diurnal pattern TG_01 for example 1
Considering the following allocation of hours to the time periods:
•
•
•
Day (D): 6-18 h (= 12 hours)
Evening (E): 18-22 h (= 4 hours)
Night (N): 22-6 h (= 8 hours)
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
 PS with diurnal
causes the following results as listed in the subsequent table:
pattern 1 - A & B.cna
Evaluation
Parameter
Calculation
Remarks
Ld
= 35 dBA
source active
permanently
during D
A
Le
Ln
L1hMaxD
L1hMaxE
L1hMaxN
 35  10lg
 4  30 min
 35  3  32.0 dBA
 4  60 min
source for (4*30)
min active during
E
B
 35  10lg
15min
 35  15.1  19.9 dBA
 8  60  min
source just 15 min
active during N
A
because emission
is constant during
D
A
= 35 dBA
 35  10lg
30 min
 35  3  32.0 dBA
60 min
source is active for
30 min during
loudest hour
B
 35  10 lg
15min
 35  6  29.0 dBA
60min
source is active for
15 min during
loudest hour
A
Again, the point source causing a receiver level of 35 dB(A) without correction for operating time is used. Then, the diurnal pattern TG_02 as shown on
the following page is selected.
Considering the following reference times for the daily periods:
•
•
•
File
Day (D): 7-20 h (= 13 hours)
Evening (E): 6-7 h and 20-22 h (= 3 hours)
Night (N): 22-6 h (= 8 hours)
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Example 2
2
24
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
 PS with diurnal
causes the following results as listed in the subsequent table:
pattern 2.cna
2
Eval.Param.
Calculation
Remarks
Lde
Ld = 35 dBA
Ld: source is permanently
active during D,
Le: source is just active for
(3*10) min during E,
Lde: considers a penalty of
6 dB for recreation/
evening period
Le
3 10  min
 35  10lg
 35  7.8  27.2 dBA
 3  60  min


1
0.1  L  6 
L de  10 lg 
13*10 0.1L d  3*10 e
  34.7 dBA
16


Ln
L1hMaxN
 35  10lg
 4  30  4 15 min
8  60  min
 35  10lg
30 min
 35  3  32.0 dBA
60 min
 35  4.3  30.7 dBA
source active for 180 min
within 480 min
loudest hour occurring
during N (last from 22-2
hours)
Diurnal pattern TG_02 for example 2
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Chapter 2 - Sound Sources
2.1.1 Common Input Data
solid angle correction K0 (dB) accord. to VDI 2714 /38/ or the directivity index D accord. to ISO 9613 /8/
The excess level in the direction of sound radiation due to reflecting surfaces
close to the source can be accounted for by a global correction, the solid
angle correction K0 or the directivity index D. Since the ground reflection is
already accounted for within the calculation according to ISO 9613-2, just the
remaining reflecting surfaces are to be considered when determining the
value of K0 (thus called „K0 without Ground“, i.e. ignoring the ground).
The concept of the directivity index refers to omni-directional radiating point
sources. In case of directional sound radiation (i.e. using a directivity pattern,
see chapter 2.2) it is recommended to set the directivity index D to 0 dB,
since otherwise the radiation - irrespective of the shape of the directivity
pattern - would be generally increased by the entered directivity index.
In case of K0 or D > 0 the reflection from the building itself (i.e. reflector
near the source) must not be included as the excess level is already accounted
for by the correction K0 resp. D. In order to maintain the building’s
reflective properties for all other sound sources the „Minimum Distance
from Source to Reflecting Object“ specified via menu Calculation|
Configuration, tab „Reflection“ (see chapter 6.2.8), has to be larger than the
distance of the source in front of the facade (e.g. 0.5 m).
see chapter 4.2.3, section "Additional Information for object „Building“"

Starting with CadnaA release version 3.6 the horizontal distance (2D
distance) is used to calculate the directivity index K0 or D - instead of
the 3D distance between source and receiver. This change causes level
differences for very different heights of source/receiver only.
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K0 without Ground
2
26
2
Chapter 2 - Sound Sources
2.1.1 Common Input Data
Examples for K0 / D
2
Source Location
K0 / D without Ground (dB)
Source at any height above the ground
(solid angle: 2)
0
Source at any height above the ground in front of a
wall (solid angle: )
3
Source at any height above the ground in a corner
(solid angle: /2)
6
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Chapter 2 - Sound Sources
2.1.2 ISO 9613
2.1.2
ISO 9613
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.

2 27
The national editions of ISO 9613 may state further application notes
(e.g.: /8/ /56/).
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2
Chapter 2 - Sound Sources
2.1.2 ISO 9613
2
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Chapter 2 - Sound Sources
2.1.3 Nordic Prediction Method 1996
2.1.3
2 29
Nordic Prediction Method 1996
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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2
Chapter 2 - Sound Sources
2.1.3 Nordic Prediction Method 1996
2
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Chapter 2 - Sound Sources
2.1.4 Nord 2000
2.1.4
2 31
Nord 2000
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this calculation procedure.
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Chapter 2 - Sound Sources
2.1.4 Nord 2000
2
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Chapter 2 - Sound Sources
2.1.5 Ljud från vindkraftverk
2.1.5
2 33
Ljud från vindkraftverk
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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2
Chapter 2 - Sound Sources
2.1.5 Ljud från vindkraftverk
2
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Chapter 2 - Sound Sources
2.1.6 BS 5228
2.1.6
2 35
BS 5228
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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2
Chapter 2 - Sound Sources
2.1.6 BS 5228
2
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Chapter 2 - Sound Sources
2.1.7 Harmonoise
2.1.7
2 37
Harmonoise
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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38
2
Chapter 2 - Sound Sources
2.1.7 Harmonoise
2
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Chapter 2 - Sound Sources
2.1.8 Concawe
2.1.8
2 39
Concawe
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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2
Chapter 2 - Sound Sources
2.1.8 Concawe
2
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Chapter 2 - Sound Sources
2.1.9 NMPB-Industry 2008
2.1.9
2 41
NMPB-Industry 2008
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this standard.
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2
Chapter 2 - Sound Sources
2.1.9 NMPB-Industry 2008
2
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Chapter 2 - Sound Sources
2.1.10 CNOSSOS-EU (Industry)
2.1.10
2 43
CNOSSOS-EU (Industry)
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this procedure.
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44
2
Chapter 2 - Sound Sources
2.1.10 CNOSSOS-EU (Industry)
2
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Chapter 2 - Sound Sources
2.1.11 Schall03 (2014)
2.1.11
Schall03 (2014)
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this procedure.
2
In Schall03 (2014), supplement 3 /26/, the acoustical characteristics of noise
sources at marshaling yards are listed. These emission datasets are available in
CadnaA (see menu Tables/Libraries (global)/Sound Levels, see also
Chapter 12 - Libraries).
Characteristics of
marshaling yards
In case these emission datasets according to Schall03 (2014) are not
displayed, proceed as follows:
Loading Emission
Datasets
•
Open the Library-Manager on the Tables menu.
•
Select the library „Sound Levels“ and the type „Default“.
•
Select the action „Copy to“ (default) with the destination „Local“ or
„Global“.
•
After clicking OK, the spectra are written to the selected library.
Sound power spectra according to Schall03 (2014), supplement 3,
for noise sources at marshaling yards
(„name“ of sound just available in German for the time being)
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Chapter 2 - Sound Sources
2.1.11 Schall03 (2014)
2
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Chapter 2 - Sound Sources
2.1.12 HJ 2.4 (2009)
2.1.12
2 47
HJ 2.4 (2009)
Beyond the source characteristics as specified in chapter 2.1.1 "Common Input Data" no further parameters are to be considered with the application of
this procedure.
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2
Chapter 2 - Sound Sources
2.1.12 HJ 2.4 (2009)
2
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Chapter 2 - Sound Sources
2.1.13 Further Procedures for Industrial Noise
2.1.13
2 49
Further Procedures for Industrial Noise
Information on the following standards or guidelines for industry can be
found in the German version of the CadnaA reference manual:
•
VDI 2714/2720, Germany
•
OEAL 28 (1987), Austria
•
DIN 18005 (1987), Germany
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2
Chapter 2 - Sound Sources
2.1.13 Further Procedures for Industrial Noise
2
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Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources
2.2
Directivity at Industrial Sources
When sound sources are not radiate uniformly in all directions, this can be
accounted for by selecting a pre-defined directivity or by entering a userdefined directivity. The calculation procedure selected for industrial noise
(see chapter 6.2.1) specifies on how to consider directivity within the
calculation of sound propagation. However, the majority of the calculation
procedure for industrial noise do not specify much detail on input and
application of directivity data. The following statements refer, as an example,
to the application of directivities in conjunction with ISO 9613-2.
The equation (3) in ISO 9613-2 /8/ introduces the directivity correction Dc:
LfT  DW   L W  D C  A
where
LfT(DW)
LW
energy-equivalent continuous sound pressure level for downwind in octave
band width, in dB
sound power level in octave band width of the point source, in dB
DC
(reference sound power (10-12 W)
directivity correction in dB, consisting of:
DC  DI  D
DI
directivity index of the point source
D
correction for sound radiation into solid angles smaller than 4 steradians
total attenuation per octave band occurring on the propagation path, in dB
A
According to the equation for LFT(DW), the directivity correction is added to
the sound power level. This requires that the directivity itself must be
normalized to a sum level of zero dB, in order not to alter the sound power
radiated by the point source. More details for input or application of
directional effects (for example, angular step-size, limitations with regard to
the ray tracing algorithm applied etc.) cannot be found in ISO 9613-2.
This statement also applies for other standards and procedures for industrial
noise.
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Directivity &
ISO 9613-2
52
2
Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources

2
Button „Directivity“
When modeling road, railway or aircraft noise directional effects may
also be considered on the source-side within the calculation of sound
propagation. In these cases, however, the directivities applied form an
integral part of the source description and can, therefore, not be
modified by the user.
In CadnaA, stands over the source dialog of industry sources (point, line,
area sources) the "directivity" are available which opens the dialog directivity.
Dialog Directivity
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Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources
Dialog Options
In order to account for non-uniformal sound radiation of industrial sources
(point, line, area sources) two types of directivities are available in CadnaA:
•
List box „Directivity“
2
predefined directivities: Select from the list box „Directivity“ a predefined
directivity. Presently, the following directivities are available:
 chimney (VDI 3733, see chapter 2.2.1)
 element & opening (ÖAL 28, see chapter 2.2.2)

•
The directivities of elements and openings according to ÖAL 28 are
independent of frequency.
user-defined directivities: Individual, frequency-dependent directivities
can be defined via the menu Tables|Libraries (local)|Directivity (see
chapter 2.2.3). When user-defined directivities have been entered, their
name will appear at the end of the list box „Directivity“ on the
Directivity dialog.
With this option (default setting), the normal direction (0 °) of the selected
directivity for point sources will point into the normal direction of a nearby
building facade. After calculation, the coordinates of the directivity vector are
shown into the corresponding input boxes „xyz“.
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Directivity, Automatic
Direction
54
2
Automatic orientation
depending on source type
2
Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources
The orientation of the directivity vector depends on the type of industrial
source. The following strategies are applied:
source type
orientation of the directivity
vector
point source
The directivity vector is pointing
into the normal direction of the
nearest reflecting building
facade, within a 1 m radius of
the point source. When no
reflecting facades are found, the
directivity vector is pointing into
+z direction (independent of the
source height).
line source
picture
vertical cross section
The directivity assigned points into
positive z direction (z=1), since the
ground is seen as a reflection surface.
The directivity vector is pointing
from the first to the last polygon
point (for each segment of the
line source).
The resulting level distribution
results from assigning the
directivity selected to each
segment of the line source.
top view
area source
The directivity vector is pointing
into the normal direction of the
area source.
The resulting distribution results
from assigning the directivity to
each point-like sub-source
within the borders of the area
source.
vertical cross section
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Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources
vertical area
source
The directivity of vector is
pointing to the right, seen from
the first to the last point.
Consequently, enter vertical
area sources at buildings
counterclockwise!
2
top view

The automatic orientation of directivity vector for point sources only
occurs nearby, reflecting worldwide, not with reflective screens or cylinders.
When activating this option the directivity vector can be individually oriented
by entering the coordinate direction xyz. The figures entered will be
Directivity Vector
normalized after calculation to the unit circle (radius R=1, x2 + y2 + z2=1).
Examples:
Vector Coordinates
Directivity vector is pointing towards the direction ...
(x, y, z) = (1, 0, 0)
... of the positive x-axis (i.e. to the "right").
(x, y, z) = (0, 0, 1)
... of the positive z-axis (i.e. "upwards")..
(x, y, z) = (1, 1, 0)
... the bisecting line between the positive x and the positive y axis
(at 45 degrees, to the „right upper corner“).
After a calculation the vector coordinates are normalized to the
unit circle, in this case (x, y, z) = (0.7071, 0.7071, 0)
[R=sqrt(0.7071^2+0.7071^2)].
see chapter 6.3 "Directivity" in the manual „Introduction to CadnaA“
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56
2
2
Chapter 2 - Sound Sources
2.2 Directivity at Industrial Sources
Exhaust Velocity (m/s)
is required to calculate the chimney's directivity according to VDI-guideline
3733.
Exhaust Gas Temperature
(°C)
as above
Wind Speed (m/s)
as above
Further information
Interpolation when
applying directivity
Directivity at reflected
rays
When evaluating of user-defined directivities (via menu Tables|Libraries
(local)|Directivity) to ray paths the following step apply:
•
For each ray (source-receiver) or (source-first reflector, see below) the
angle to North direction is determined.
•
Depending on the directivity vector and the ray‘s direction the relevant
directivity correction is determined for each ray. For ray directions
between two angular steps of 15° (see chapter 2.2.3) the directivity
correction results from linear interpolation.
•
The directivity index DI is added to the correction for solid angle D - if
any - and considered as DC in the calculation of propagation (see chapter
6.5 "Calculation Protocol").
The calculation procedures - e.g. also not ISO 9613-2 - do not specify how to
handle the directivity correction in conjunction with the reflected rays. In
CadnaA, the following strategy is used:
•
In case of reflected rays - independent of the reflection order - the first
section of the ray (from the source to the 1st reflector) determines the
direction being used to evaluate the relevant directivity correction.
•
This directivity correction is used, even if the ray, possibly after multiple
reflections, arrives at the receiver from a different direction.
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Chapter 2 - Sound Sources
2.2.1 Sound Radiation from Chimneys or Stacks
2.2.1
Sound Radiation from Chimneys or Stacks
The directional sound radiation of chimney outlets can be estimated by
applying a method developed in a research project funded by th German
Environmental Protection Agency (UBA) from 1981 /45/.
Radiation
Characteristics
of Chimneys
The simplified approach to determine the radiation characteristics of chimneys and cooling towers is valid with the following conditions:
Range of Application
•
diameter of the chimney opening d = 5 to 7 m
•
•
•
wind speed WL  3 ms-1
emitted medium: CO2, temperature range TF = 473 to 773 K
emitted medium: steam, temperature TF = 308 K
The following figure shows the geometrical situation:
Directivity Correction
Radiation by chimneys and stacks
The angle  calculates from:
–1
2
2
–4
–1
 = 90 + arc tan  h  s  – arc sin  h + s  10  – arc tan   W L  T F   W F  T L  
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2
Chapter 2 - Sound Sources
2.2.1 Sound Radiation from Chimneys or Stacks
Directivity Index K (in dB):

2
f in Hz
63
125
250
500
1000
2000
4000
8000
30°
2,0
2,5
2,5
3,6
3,0
2,0
2,0
2,0
45°-60°
4,0
4,8
3,2
4,1
4,8
4,8
4,8
4,8
75°
1,0
1,5
1,5
1,5
0,8
0,5
0,5
0,5
90°
-2,0
-2,5
-3,0
-3,5
-4,8
-5,6
-5,6
-5,6
105°
-4,0
-5,5
-7,0
-9,0
-10,0
-10,6
-10,0
-10,0
120°
-5,0
-7,5
-9,2
-11,5
-15,2
-19,8
-20,0
-20,0
The following parameters are used (see the preceding figure):
Example
•
•
h
s
source height (relative to the receiver) [m]
distance receiver-source (z coordinate) [m]
•
•
WL
TF
downwind velocity [ms-2]
temperature of the exhaust gas/medium [K]
•
•
WF
TL
velocity of the exhaust gas/medium [ms-2]
ambient temperature [K]
see chapter 6.4 "Radiation from Stacks and Chimneys" in the manual
„Introduction to CadnaA“
see also:
chapter 6.2.9.1 "ISO 9613". section "Sources in Building/Cylinder do not
shield" (or any other chapter in chapter 6.2.9 "Industry Tab")
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Chapter 2 - Sound Sources
2.2.2 Sound Radiation from Elements & Openings
2.2.2
2 59
Sound Radiation from Elements & Openings
The Austrian guideline OEAL 28 „Sound radiation and sound propagation“
(title translated from German, edition Dec. 1987 /54/) specifies frequency
independent directivities for the radiation by building elements and by
openings. within the building‘s facade The directivity for the radiation by
building elements has been modified with the amendment of 2001 /55/.
Directivities according to ÖAL 28 on the Directivity dialog
After withdrawal of ÖAL 28 guideline (replaced by ÖNORM ISO 9613-2) a
so-called „instruction note for modeling the sound propagation according to
ÖNORM ISO 9613-2: 2008 and ÖNORM EN 12354-4: 2001-02-01“ /62/
emphasizes that the guideline regarding the specifications for sound radiation
„is still valid“. Furthermore, it has been clarified that the directivity
correction for elements just „applies to elements with low bending stiffness
while „... for heavy building elements no specific directivity correction has to
used“ (translated from German). The instruction note refers to the
amendment of ÖAL 28 guideline from February 2001 as mentioned before.
In CadnaA there are three ÖÄL specific directivities available:
•
Element (ÖAL28): according to edition December 1987
•
Opening (ÖAL28): according to edition December 1987
•
Element (ÖAL28/01): according to amendment ÖAL28, February 2001
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2
Chapter 2 - Sound Sources
2.2.2 Sound Radiation from Elements & Openings
Directivity Correction
 L
2
Directivity with angle 
(hatched: radiating surface)
Depending on the angle  referring to the surface normal the following
expressions for the directivity correction L apply:
Directivity of elements,
edition 1987
85     135  :
 

L  3   3 
 dB
 42.5 
L  3 10lg  0.4    90   3  dB
135    180 :
L  10 dB
0     85 :
Directivity diagram (surface normal pointing in direction 0°):
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Chapter 2 - Sound Sources
2.2.2 Sound Radiation from Elements & Openings
0     85 :
85     107.5  :
L  0 dB
L  10lg  0.4    90   3 dB
Directivity of elements
with low bending stiffness, edition 2001
107.5    180 : L  10 dB
Directivity diagram (surface normal pointing in direction 0°):
0     45  :
L  4 dB
85     135  :
 90   
L  6lg 
 dB
 10 
L  2  6 lg  0.4    90   3  dB
135    180 :
L  10 dB
45    85  :
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edition 1987
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2
Chapter 2 - Sound Sources
2.2.2 Sound Radiation from Elements & Openings
Directivity diagram (surface normal pointing in direction 0°):
2
Application
In practice, radiating elements and openings are parts of the outer envelope
of buildings. In this case, the directivity vector is by default directed
automatically (see chapter 2.2, section "Automatic orientation depending on
source type").
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Chapter 2 - Sound Sources
2.2.3 Frequency-dependent Directivity
2.2.3
2 63
Frequency-dependent Directivity
Besides of the predefined directivities user-defined frequency dependent
directivities can be entered in CadnaA and be assigned industrial sources. To
this end, select from the on the Tables|Libraries (local) menu the library
Directivity. Insert a new row via the table‘s context menu and double-click
into this line to open the dialog.
Dialog Directivity containing no data
The dialog shows a table in which the directivity index can be entered in
octave bandwidth from 31.5 Hz to 8000 Hz at increments of 15 degrees. The
directivity pattern is axial-symmetrical in a plane, pointing in forward
direction (0 degrees). The directivity vector can be freely oriented on dialog
Directivity of each industrial source (by specifying the xyz coordinates of the
directivity vector, see chapter 2.2).
In case the directivity index is unknown for certain angles, the respective
input boxes remain empty. After closing the dialog, CadnaA adds the missing
angular steps by linear interpolation.
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2
Option „normalized“
2
Chapter 2 - Sound Sources
2.2.3 Frequency-dependent Directivity
With the option „normalized“ activated, the directivity correction is
increased or reduced by a constant factor for all directions in a way that the
sound power level specified on the source dialog remains unchanged with
this directivity selected.
This option enables to enter octave band sound pressure levels having been
measured in the vicinity of the source. In this case, the entered values are not
changed, but maintained.
Paste
Clicking the „Paste“ button enables to paste data formatted as text (ASCII
format) with tabulators (TAB) as separators for columns and RETURN for
rows from the clipboard into the dialog table. The data may either use
decimal points or decimal commas.
The data is always inserted starting from the upper left cell (0° at 31.5 Hz).
The current cursor location is not relevant. Therefore, the data should be
formatted correctly by inserting missing octaves or angular steps by empty
columns or rows.
Import of directivities via
ODBC
Directivities can also be imported via the ODBC connection (see chapter
7.3). To this end, select from the dialog File|Database|Definition the
object type „Directivity“ (at the end of the list).
The attribute of the directivity index has the structure „Sxxx_yyyy“ where:
•
•
xxx: angle 0 to 180 degrees
yyyy: frequency 31 to 8000 Hz
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Chapter 2 - Sound Sources
2.2.3 Frequency-dependent Directivity
In the following, the level distribution of an engine test run at an aircraft has
been pasted via the clipboard:
Example
2
Frequency-dependent directivity index in 30° steps.
No data is available for the remaining angular steps.
After closing and reopening the dialog the missing angular steps have been
updated by interpolation:
Frequency-dependent directivity index, missing angular steps
have been filled in by interpolation
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2
Chapter 2 - Sound Sources
2.2.3 Frequency-dependent Directivity
In order to assign this directivity click the „Directivity“ button on the edit
dialog of a point, line or area source and select the given name of the
directivity from the list box „Directivity“.
2
Selecting the directivity
Detailed Example
see chapter 6.3.3 "Frequency Dependant Directivities" in the manual
„Introduction to CadnaA“
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Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
2.3
Tennis - Point-of-Serve
The noise by tennis courts, especially when multiple courts are operated
simultaneously, consists of a sequence of short impulses resulting from the
impact of the tennis balls, causing an increased annoyance.

In the German legislation, the assessment of noise caused by sports
facilities is characterized by the A-weighted maximum level LpAFT
during a time interval of 5 seconds. This maximum level for each
interval of 5 seconds corresponds with the maximum level applying the
time weighting „FAST“ /107/.
The tennis source in CadnaA is a point source the emission of which is not
entered, but set automatically /42/. For the calculation of propagation the
selected industrial standard/guideline is used. With ISO 9613-2 it shall be
noted that the non-spectral ground attenuation has to be selected (see chapter 6.2.9.1, section "Ground Attenuation"). In this case, the ground reflection
is considered automatically by the directivity index K0 or D resp. based on
the source height above ground (corresponding to K0=3 dB as stated in VDI
3770 /42/).

2
Since the emission of the tennis source refers specifically to the
assessment procedure established by the German legislation, it has to be
decided whether this type of source is applicable in other countries and
in a different legal context.
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Tennis Source
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2
2
Source in SteadyState / Operating
Time
Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
By default, the option „Source in Steady-State“ is selected where no
correction for operating time applies. In this case, the specified noise
emission is constant for each entire daily period (see chapter 6.2.4).
Dialog Tennis - Point-of-Serve, with option „Source in Steady-State“
By selecting the option „Operating Time“, the source-specific operating time
in minutes can be entered for each daily period „Day|Recreation
(=Evening)|Night“. The correction for operating time result from the
operating times and the reference time intervals D|E|N specified in the configuration of calculation (see chapter 6.2.4).
Dialog Tennis - Point-of-Serve, with option „Source in Steady-State“
Addressing
Diurnal Patterns
Furthermore, diurnal patterns (= hourly emission profile covering 24 hours)
can be used for the tennis source in CadnaA. To this end, first define a diurnal pattern with the application type „Industry“ in the local or the global library „Diurnal Patterns“ (see chapter 12.3). Subsequently, this diurnal pattern
can be selected from the list box.
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Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
When tennis is played during the entire period for Day/Recreation
(Evening)/Night the option „Source in Steady-State“ is used.
Evaluation
2
Only when tennis is played just for a part of a period, the operating time and
the reference time on tab „Reference Time“ (see chapter 6.2.4) have to be
specified. The result is then displayed for the first evaluation parameter (Ld).

Alternatively, a diurnal pattern could be used in the evaluation. Whether
this is more useful or not, depends on the local legal prescriptions
made. If the official approval just depends on a set of sensitive hours
(e.g during Sundays or public holidays) the evaluation of just this period
may be sufficient (i.e. not requiring to use diurnal patterns).
It is useful to name the courts and the points of serve properly (and the ID).
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2
Geometry
2
Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
Per default, the source height is 2 m above ground (according to VDI
guideline 3770 /42/).
The points of serve are entered on the middle of the base line of a tennis
court.
Hier den
Tennisaufschlagpunkt plazieren

When modeling playing doubles in tennis, not twice as many points-ofserve are entered, as the number of events does not depend on the type
of game.
According to /42/, each tennis point-of-serve gets a sound power level
assigned which depends on the distance to the receiver. This approach
requires to sort the sources for each receiver by distance source-receiver and
to assign the respective sound power level. This sorting and allocation occurs
automatically when using the tennis source.

This emission model is not consistent with other (industrial) sources
where constant emission is assumed. The emission model considers the
fact that points-of-serve being closer to or unscreened with respect to
the receiver point dominate the noise level, while more distant or
screened points-of-serve are less or not relevant.
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Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
The following approach is used to address the emission automatically:
•
For each source Q1..Qn the total attenuations Rn,i are determined for
each receiver i: Rn,i = PWLn - SPLn,i

The total attenuations Rn,i are evaluated using the industrial guideline
selected in CadnaA.
•
Sorting of the source points where source Q1 has the smallest attenuation
and Qn the largest one. For unobstructed propagation this procedure
corresponds to a sorting by distance source-receiver.
•
The sources Q1 to Qn are given the following sound power levels.
n
PWLn
1
2
3
4
5
6
7
8
9
10
89.8
88.2
86.7
85.1
83.6
82.0
80.5
78.9
77.4
75.8

The emission of the tennis source does not depend on the daily period
D/E/N.

These values apply also when doubles is played.
•
Energetic addition of all levels at each receiver.
Even with grid calculations, just the 10 closest tennis sources cause a noise
impact at each grid point (assuming free propagation).
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(detailed)
2
72
2
Example
2
Chapter 2 - Sound Sources
2.3 Tennis - Point-of-Serve
The following example shows 8 tennis courts with 16 points-of-serve. In the
calculation, just the 10 sources closest to the receiver contribute. The emission from more distant sources is irrelevant at this receiver.
 Examples\
\02_Sources\Tennis\
tennis.cna
By replacing these 10 tennis sources by point sources and addressing the
distance-dependent sound power levels as from the table, would result in the
same receiver level.
Simplified Emission
Model
The simplified emission model described in the VDI guideline 3770 /42/
uses point sources at each point-of-serve, all having a (constant) A-weighted
sound power level of PWL=90 dB(A) (at 2 m height). This simplified
approach leads, however, to an overestimation of the receiver levels
compared with the detailed emission model described above. So, in case
limiting values are satisfied using the simplified emission model they will be
as well using the detailed emission model.
CadnaA - Reference Manual
Chapter 2 - Sound Sources
2.4 Roads
2.4
Roads
The sound source „Road“ is radiating to all sides as long as the option „SelfScreening“ is not activated (see chapter 2.4.1 "Common Input Data", section
"Self-Screening").
Radiation from sound source „Road“,
relative height 0 m (for RLS-90)
Radiation from sound source „Road“,
relative height 10 m,
option „Self-Screening“ deactivated
Radiation from sound source „Road“,
relative height 10 m,
option „Self-Screening“ activated
The object „Road“ may have different values at each polygon point for the
following parameters:
•
•
•
2 73
the road’s cross section or width (see chapter 2.4.1, section "Specification
of Road Width")
the lateral slope (see chapter 2.4.1), and
the height (see chapter 4.2).
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2
2
Chapter 2 - Sound Sources
2.4 Roads
The command Parallel Object (see manual „Introduction to CadnaA“) on
the context menu of a road enables to generate barriers, embankments, or
contour lines at a specified distance parallel to the road’s axis or to generate
station marks into the direction of the road using the command Generate
Station (see manual „Introduction to CadnaA“).
Commands on the context menu of the object „Road“
The parameters of a road are entered in edit mode on the dialog Road that
opens when double-clicking on the road’s centre line.

The subsequent chapters are specific for each standard or guideline
available in CadnaA. These specifications do not represent a copy of
the standardized procedures, rather the way they are implemented.
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Chapter 2 - Sound Sources
2.4.1 Common Input Data
2.4.1
Common Input Data
When clicking the file selector symbol to the right of the input box „SCS/
Dist. (m)“ in the dialog Road the dialog Road Width is displayed enabling to
enter, either the distance of the center lines of the outer lanes (location of the
noise sources), or the total width of the road from curb to curb (in m).
Alternatively, the predefined cross sections can be selected. Roads having a
road width > 0 m have two lanes whole roads with a road width = 0 m will
have a single lane only.
Specification of Road
Width
The road width represented on the screen corresponds to the entered width
only in case the additional width (at the curb) is set to 0 m (see below, section
"Display real Width of Roads"). In this case, the borders of the object „Road“
represent the centre lines of the outer lanes (noise sources).
Distance of the outer
lanes
The road width displayed on screen does not correspond to the entered
width because a default distance of 1.75 m is presumed between the centre
lines of the outer lanes to the curb. Therefore, a road with a total width of e.g.
10 m from curb to curb has a distance of 10 - (2*1,75) = 6,5 m between the
centre lines of the outer lanes.
Total width of road from
curb to curb
On Options|Appearance menu the additional width between the emission
lines and the curb can be defined globally (object type „Road“). The value
entered represents the sum of the curb’s distance left/right. Mark the object
„Road“, select the first type of layer „Simple“, and enter the required
additional width.
Display real Width of
Roads
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2
Chapter 2 - Sound Sources
2.4.1 Common Input Data
2
Appearance dialog for object type „Road“: additional width for distance to curb
Via the second type of layer „Simple“ the appearance of the centre lines of
the outer lanes (sound source locations) can be defined. The settings concern
all roads globally.
Appearance dialog for object type „Road“: for sound source appearance
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Chapter 2 - Sound Sources
2.4.1 Common Input Data

2 77
The centre line of the object „Road“ will always be displayed as a centre
line, irrespective whether the real road has a single or several lanes in
each direction (e.g. highway).
2
Road with additional width: emission lines and curbs
Standard Cross Section
(SCS)
The standardized cross sections can be selected from the list with the mouse
and clicking OK. The standardized cross sections result from the following
German standards:
•
Richtlinien für die Anlage von Straßen RAS, Teil: Querschnitte RAS-Q,
Ausgabe 1982 /18/ und 1996 /19/, Forschungsgesellschaft für Straßenund Verkehrswesen, Arbeitsgruppe Straßenentwurf, Köln.
•
Entwurfshinweise für planfreie Knotenpunkte an Straßen der Kategoriengruppe B, RAS-K-2-B, Ausgabe 1995 /21/.
•
Aktuelle Hinweise zur Gestaltung planfreier Knotenpunkte außerhalb
bebauter Gebiete, AH-RAL-K-2, Ausgabe 1993 /22/.
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2
Examples for Roads
2
Chapter 2 - Sound Sources
2.4.1 Common Input Data
In the subsequent section some examples are given for the input of roads.
Example 1: Single Lane
Road
For a single-lane road, enter 0 in the input box „Standard Cross Section/Distance“ on the dialog Road or, if 0 is displayed as the default value, leave it unchanged. In this case just a single emission line exists.
Example 2: Multi-lane
Road
For a multi-lane road, enter either the distance between the centre lines of the
outer lanes, or select the appropriate predefined cross section. For example,
when selecting the standard cross section „a6ms“ according to RAS-Q 82 /
18/, a distance of 24.75 m results between the centre lines of the two outer
lanes. This corresponds to the road width displayed on the screen (with an
additional width of 0 m).
Example 3: Road
widening from 1 to 2
Lanes
In order to alter the distance of the outer lanes or the lateral slope along a
road, each polygon point is edited individually via the dialog Geometry (see
chapter 4.2). Proceed as follows.
•
Open the dialog of the respective road.
•
Click the button „Geometry“ and double-click into a row of the geometry
list.
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2.4.1 Common Input Data
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2
Dialog Road: Point
•
On the dialog Road: Point, enter the appropriate values for the distance
between the axis’ of the outer lanes.
•
Access the next or previous polygon point via the arrow buttons.
Via the button „New“ a new point is inserted. The road’s polygon point being edited is flashing on the screen. In order to see this, the dialog box may
have to be moved apart. To keep the road width constant in the direction of
geometry, it does not require to edit every polygon as the entered distance is
kept until it is changed at a further point.
Widening of a road from 1 to 2 lanes
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2
Example 4: Crossing with
continuous lanes
Chapter 2 - Sound Sources
2.4.1 Common Input Data
The next example shows a crossing with continuous lanes.
2
In CadnaA, just enter the two intersecting roads. In case the traffic densities
of the four combining road sections are different, it needs to model this road
crossing from four road sections joining in the middle of the crossing.

Regarding the use of traffic lights see chapter 2.5.
Even when two road sections each are supposed to join in the middle of the
crossing, the straight through-lanes are entered first and can be split
afterwards.
Splitting of Roads into
Sections
Option 1: Open the context menu by clicking on the centre line of the road
with the right mouse button. Selecting the command Break Lines from the
context menu splits the crossing roads right in the middle. This can be
checked by clicking on the split road selecting just a half of it. Subsequently,
by clicking one of the split road sections, select the command Break Lines
once again, the non-split road will be split.

Deactivate other objects - if any - being intersected by the roads in
order not to be split as well.
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2.4.1 Common Input Data
2 81
If this is the case, and the other objects shall not to be split, proceed as
follows.
2
Option 2: Instead of using the crossing roads as intersection lines for
splitting, draw an auxiliary line - for example, a line source or an auxiliary
polygon - on top of the centre line of the road to be split, and apply the command Break Lines from the context menu of this auxiliary line in order to
split the road. Then, delete the auxiliary line. After splitting of the roads, different parameters such as traffic densities can be defined for the individual
road sections.
for further options see the manual „Introduction to CadnaA“.
Example 5: Crossing with
Filter Lane
This example is a combination of the scenarios already dealt with. At the
transitions from the two-lane roads to the crossing and within the area of the
crossing, the lanes are modeled from roads with a road width of zero. These
are followed by two-lane roads in all four directions.
Any other geometry may be derived from those examples.
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2
Lateral Slope
2
Chapter 2 - Sound Sources
2.4.1 Common Input Data
On the dialog Road: Point, the lateral slope can be defined - besides the outer lanes’ distance - from point to point (via button „Geometry“ of the road).
The lateral slope refers to the outer lanes’ axis which is rotated around the
road’s centre line. A positive value lifts the outer right lane, a negative value
the outer left lane. „Right“ and „left“ refer to the initial point when looking
towards the final point.

Emission in dB(A)
The entered slope holds also for all subsequent points into the direction
of geometry. A new value needs to be entered only when the lateral
slope changes again at a further point. Starting from this point, this new
value holds again for all subsequent points.
The sound emission of a road is characterized by an emission level which is
usually specific to the standard or guideline applied. This value is either entered directly or derived from road specific parameters for the selected road
standard or guideline (see subsequent chapters specific to each standard/
guideline).
Traffic Density
Counts, MDTD
Average daily traffic density (normally: vehicles per 24 hours): This is the
number of vehicles passing a section of the road per day, averaged over the
entire year.
Road Type
With the option „Counts“ selected, this list box enables to select the road
type according to the selected standard. Based on this classification, default
values for the hourly traffic density and for the proportion of trucks are used.
The road types specific to the selected road noise standard can also be
assigned using the attributes STRGATT or STRGATT_NR. For details, see
the chapter for each road noise standards below.
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Chapter 2 - Sound Sources
2.4.1 Common Input Data
Further, the emission of a road can be described by a diurnal pattern
containing hourly traffic data. Diurnal patterns can be defined in the global
or in the local library (see chapter 12.3). After having defined a diurnal pattern in the global or local library its ID code can be selected from the list box
„Road Type“.
Diurnal Pattern
2
Diurnal Pattern TG_1 selected on list box „Road Type“

User-defined diurnal patterns can be assigned by using the attribute
STRGATT (thus not by the attribute STRGATT_NR).
When the option „Precise Counts“ is activated, the relevant hourly traffic
density M (in vehicles/hour) for the periods Day|Evening|Night and the
mean proportion of trucks p% can be entered (vehicles with a gross mass
> 2800 kg as percentage of the relevant traffic density).
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2
Speed Limit (km/h)
2
Chapter 2 - Sound Sources
2.4.1 Common Input Data
This is the maximum speed, in km/h, permissible on the relevant road
section for autos and trucks. This speed is taken into account according to
the selected standard for autos and trucks. The default value for trucks is the
same for cars. In case a different speed limit applies for trucks, activate the
check box „Truck“ and enter the speed limit for trucks.

Information on the minimum and maximum speeds for each road noise
standard is given in the subsequent chapters.
Button DEN
When clicking the symbol
speed limits can be entered separately for autos and trucks and for the time periods Day|Evening|Night.
Road Gradient (%)
The road gradient in % can either be entered by the user or calculated
automatically, respecting the individual height profile of the road. The available options are selectable from the list box „Road Gradient“.
Dialog Road with list box „Road Gradient“
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Chapter 2 - Sound Sources
2.4.1 Common Input Data
With selection of „Road Gradient: auto“ the gradient of roads made of
several road sections is calculated automatically. In this case, the displayed
emission value (e.g. Lm,E with RLS-90) does not consider any gradient
correction (also, not the tabulated emission value on menu
Tables|Sources|Road). The gradient correction, however, is calculated for
each road section automatically and considered within the calculation of
propagation.
Select from the list box „Road Gradient“ into which direction the traffic
flows on the two outer lanes. The abbreviations VA, AV, AA and VV
designate the traffic direction on the outer lanes, as seen from the first to the
last point of the road (see figure below).
Road geometry and traffic directions
The letter „A“ and „V“ can be understood as arrowheads. For example, in
case of traffic direction VA the traffic flow is - seen from the first point of the
road - on the left outer lane into the opposite direction of the geometry
points and on the right outer lane into the direction of the geometry points.

The type of road gradient can also be specified by using the attributes
STEIG and STEIG_AUTO (see CadnaA-manual „Attributes,
Variables, and Keywords“).
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Calculate Road Gradient
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2.4.1 Common Input Data
When selecting the command Calc Gradient of Roads from the Extras
menu, CadnaA calculates the average gradient in % for all active roads based
on their z-coordinates and the digital terrain model. The result is displayed
and used as road gradient.

Because the value applies for the entire road, the gradient is calculated
from the height difference of the first and the last point of the road’s
entire length. Otherwise, the road has prior to be broken into pieces (by
the command Break into Pieces, with the option „Split at Polygon
Points“) before calculating the gradient.
The gradient calculation using the command Extras|Calc Gradient of
Roads occurs for all active roads simultaneously. In case this is not intended,
deactivate those roads which are to be excluded from the gradient’s
calculation and reactivate them afterwards.
Dialog Geometry
Source Height
The height entered in the dialog Geometry is the surface height of the road.
Depending on the selected standard for road noise the source height (e.g. 0.5
m with RLS-90) is added for calculation. Thus, the road’s z coordinate is
always the surface height.
Self-Screening
When the option „Self-Screening“ on the dialog Geometry is activated the
road is just radiating into the upper half sphere. For the lower half sphere a
screening effect occurs for all receivers below the road surface. This feature
enables to define inclined roads, either upwards or downwards, by allocating
the height above (relative) ground or an absolute height to every point of the
road, and by defining an additional width (e.g. considering sidewalks etc.).
Since the option „Self-Screening“ is available, the use of the object „Bridge“
became superfluous (see chapter 3.3).
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When selecting a predefined cross-section (see chapter 2.9.1) the respective
additional width referring to the entire road profile is copied to the input
boxes "Additional Width". This feature facilitates the consideration of
ground absorption for the entire road width (see chapter 6.2.7).
By default, the road width as displayed by CadnaA results from the sum of
the width between axis of the outer lanes and the additional width as defined
on dialog Options|Appearance (see also section "Specification of Road
Width", default value: 3.5 m).
2
Additional Width left/
right
With the self screening-option activated, the actual road width can be
specified by entering an additional width > 0 m. The additional width can be
defined separately for either side of a road. A specified additional width overwrites the additional width defined on dialog Options|Appearance. These
additional width is also displayed in the plan view and on the 3D-special view.
In addition, parapets (e.g. parallel barriers) for the self-screening road can be
defined, either on one or both sides by entering a height left/right > 0 m.
The parapets are treated as fully absorbing on either sides. This characteristic
cannot be changed. Absorbing or reflecting barriers without or with cantilever can be defined just by using the object „Barrier“ (see chapter 3.2).
The following requirements and properties are to be respected:
•
In any case, the additional width has to be > 0 m.
•
The screens defined via option „Self-Screening“ are a characteristic of the
road and are not displayed in the 2D-graphics, but just on the 3D-Special
view (see chapter 9.14).
•
Barriers defined via option „Self-Screening“ will just screen the own
source (road), but not the noise from other kinds of sources.
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right
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2
Station from/up to
2
Chapter 2 - Sound Sources
2.4.1 Common Input Data
This option enables to restrict the length of the barrier along the road’s axis
with reference to the stationing. In this case, the barrier is just generated for
the range „from-up to“.
This option is particularly useful when modeling bridges in order to suppress
the diffraction around the edge of the road sections (road width) at bridgeheads.
For the automatic assignment two attributes are available:
•
•
Only for Ground
Absorption, no Screening
station start:
station end:
SSCR_ST_B
SSCR_ST_E
With this option being activated, the additional width entered will not cause
any screening effect, but will just be considered when calculating ground absorption. This requires, however, that the respective option on the configurations is checked (dialog Calculation|Configuration, tab „Ground
Absorption“, option „Roads/Parking Lots are reflecting G=0“, see chapter
6.2.7). With this option activated the speed of calculation may increase considerably due to the omission of barrier calculation.
The self-screening effect of the road’s surface - including parallel barriers, if
any - just refers to the respective road itself. Thus, the parallel barriers
(parapets) defined via „Self-Screening“ are not seen by other sources.
Additional information
The height of the road source above the road‘s surface depends on the
selected road noise standard. The height on the dialog Geometry of the
object "Road" refers to the road surface.
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2.4.2 RLS-90
2.4.2
RLS-90
The emission parameter according to RLS-90 is the mean level Lm,E at 25 m
distance from the road’s axis of an infinite straight road with free sound
propagation /17/:
Emission Parameter
Lm,E = Lm + Dv + DStrO + DStg
where
Lm: mean level at 25 m distance
Dv: speed correction
DStrO: correction for road surface
DStg: correction for road gradient
Dialog Road (for RLS-90)
The mean level Lm calculates from:
Lm  37.3  10 lgM * 1  0.082 * p 
where
M: hourly traffic, i.e. mean number of vehicles of hour
Note - For multi-line roads the hourly traffic is split by 50/50 for each lane.
p: portion of trucks in % (trucks with a maximum mass of more than 2800 kg)
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Emission Level Lm
2
90
2
MDTD - RLS-90
2
Chapter 2 - Sound Sources
2.4.2 RLS-90
Specifying the „Mean Daily Traffic Density“ (MDTD, veh/24h) calculates
the emission level Lm,E depending on the road type based on the hourly traffic data M (veh/h) and the truck portion p (%) according to the table below.
accord. to RLS-90, table 3:
Attribute Value
STRGATTNR
MDTD - VBUS
daytime
(6-22 h)
nighttime
(22-6 h)
M
(veh/h)
p
(%)
M
(veh/h)
p
(%)
0
Motorway
0.06 DTV
25
0.014 DTV
45
1
Federal Road
0.06 DTV
20
0.011 DTV
20
2
Ordinary Road
0.06 DTV
20
0.008 DTV
10
3
Local Road
0.06 DTV
10
0.011 DTV
3
With the options „Strictly accord. to RLS-90“ deactivated and the option
„Calculation accord. to VBUS“ activated (both on tab „Road“, menu
Calculation|Configuration) the following hourly traffic data M (veh/h)
and the truck portion p (%) will be used /115/:
Attribute Value
STRGATTNR
Source Geometry
Road Type
Road
Type
Day
(6-18 h)
Evening
(18-22 h)
Night
(22-6 h)
M
(veh/h)
p
(%)
M
(veh/h)
p
(%)
M
(veh/h)
p
(%)
0
Motorway
0.062 DTV
25
0.042 DTV
35
0.014 DTV
45
1
Federal
Road
0.062 DTV
20
0.042 DTV
20
0.011 DTV
20
2
Ordinary
Road
0.062 DTV
20
0.042 DTV
15
0.008 DTV
10
3
Local
Road
0.062 DTV
10
0.042 DTV
6.5
0.011 DTV
3
The height entered in the dialog Geometry is the height of the road’s surface.
The source height is 0.5 m above the road’s center line or above of the center
lines of the outer lanes.
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2.4.2 RLS-90
The minimum speed according to RLS-90 is 30 km/h for all types of
vehicles. The speed limits are 130 km/h for autos and 80 km/h for trucks. In
case a speed below 30 km/h is entered, 30 km/h is applied instead. With a
speed limit > 130 km/h a speed of 130 km/h for autos and of 80 km/for
trucks is used.
Speed Limit (km/h)
2
The speed correction Dv calculates from:


100  100.1D  1 p 
Dv  Lcar  37.3  10 lg 

 100  8.23 p 
with

Lcar  27.7  10 lg 1  0.02vcar 
3

and
D  Ltruck  Lcar where Ltruck  23.1  12.5 lg vtruck
where
vcar: speed limit for autos/cars (30<=vcar<=100 km/h)
vtruck: speed limit for trucks (30<=vcar<=80 km/h)
Lcar, Ltruck: mean level Lm for a one auto/car or truck per hour
p: proportion of heavy vehicles (in %)
The correction for different road surfaces DStrO can be entered or selected
from the list box providing the road surface types of RLS-90. To this, at first
the corresponding option button has to be activated. By default, the road surfaces listed in a following table are available.
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Chapter 2 - Sound Sources
2.4.2 RLS-90
accord to RLS-90, table 4, and amendment (Rundschreiben Straßenbau Nr.
14/1991, Ed.: BMV):
2
Attribute
Value
STRONR *)
DStrO in dB(A) at a
speed of
Road Surface
< 40
km/h
< 50
km/h
<= 60
km/h
> 60
km/h
1
smooth mastic asphalt, asphalt
concrete or blinded mastic asphalt
0
0
0
0
2
concrete or corrugated mastic
asphalt
1
1,5
2
2
3
pavement with a smooth surface
2
2,5
3
3
4
other pavements
3
4,5
6
6
5
concrete according to ZTV Beton
78 with steel broom stroke
-
-
-
1
6
concrete according to ZTV Beton
78 with steel broom stroke and
with smoothing tool
-
-
-
-2
7
asphalt concrete <= 0/11 and
blinded mastic asphalt 0/8 and 0/
11 without grit
-
-
-
-2
8
open-pore asphalt covering layers
containing at least 15 % of voids,
when new, with 0/11 grain size
-
-
-
-4
9
open-pore asphalt covering layers
containing at least 15 % of voids,
when new, with 0/8 grain size
-
-
-
-5
Notes:
1. For low-noise road surface materials which have proved to provide a lasting noise reduction due to recent
technological developments in structural engineering, different DStrO corrections may be taken into account.
2. The corrections for rows 5 to 9 apply just to roads outside towns with a speed limit > 60 km/h.
3. The classes for the speed limit have been rearranged for software design reasons.
*) The attribute value STRONR=0 selects the numerical input of DStrO.
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2.4.2 RLS-90
The road gradient g can be entered in % or be calculated automatically,
depending on the z-heights of the road. The list box „Road Gradient“ on the
Road dialog offers different options (see chapter 2.4.1, section "Road Gradient (%)").
DStg  0.6  g  3
for |g| > 5%
DStg  0
for |g| <= 5%
First-order reflections are to be taken into account by first-order mirror
sound sources according to RLS-90. When the option „Strictly according to
RLS-90“ on the tab „Road“ (Calculation|Configuration menu, see Chapter 6.3.11) is activated, this occurs automatically. This is also the case if a different order of reflection is specified on the tab „Reflection“ (see Chapter
6.3.9). A calculation without any reflections can be engaged only by deactivating the option „Strictly according to RLS-90“ and specifying no order of reflection (i.e. zero).
Gradient (%)
2
Correction for Multiple Reflections
With building rows on both sides of a road, the resulting excess level has to
be accounted for by an additional correction for multiple reflections which
depends on the average height of the buildings left/right and on the distance
among them. According to RLS-90 a correction for multiple reflections applies only when percentage of gaps between the buildings is less than 30%.
This is the excess sound level due to multiple reflections. When this option is
activated a correction (in dB) for multiple reflections can be entered.
Alternatively, the correction is calculated from the average height of the
buildings on each side of the road, and the average distance (in m) between
the buildings on both sides of the road according to:
 between reflecting buildings (percentage of gaps < 30%):
Drefl  4 * hBeb / d Beb  3.2 dB
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Chapter 2 - Sound Sources
2.4.2 RLS-90
 between absorbing buildings:
Drefl  2 * hBeb / d Beb  1.6 dB
2
 between highly absorbing buildings:
Drefl  0 dB
Average Height (m)
average height of the buildings (attribute HBEB)
Distance (m)
average distance between the buildings (attribute ABST)
Absorption
absorption of the buildings (reflecting, absorbing or highly absorbing).

According to RLS-90, the correction for multiple reflections - when
specified - is applied independently from the receiver’s distance. In
CadnaA, the correction for multiple reflections is considered in the
road’s emission level (see calculation protocol).
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Chapter 2 - Sound Sources
2.4.2 RLS-90
The command Calc Width of Roads (Extras menu) calculates the average
height, the average distance and the proportion of gaps between buildings
parallel to the roads. The results are stored in string variables stored on the
dialog Memo-Window of the corresponding road..
DBEB_L; DBEB_R
average distance between the buildings (left/right)
HBEB_L; HBEB_R
average height of the buildings (left/right)
LUECK_L; LUECK_R
percentage of gaps (left/right)
Calc Width of Roads
2
Dialog Memo-Window with the corresponding string variables
after using the command Calc Width of Roads.
By copying those values to the respective input boxes on dialog Road the
Correction for Multiple Reflections can be evaluated using CadnaA (see subsequent example).
•
Open the file XL_01.cna.
 Examples\05_Immis-
•
Select the command Calc Width of Roads (from Extras menu)
sions\Option
XL\XL_01.cna
First, the calculated average height of the buildings is copied to the input box
„Average Height (m)“ on the dialog Road. To achieve this, the values of the
string variables HBEB_L (average height, left) and HBEB_R (average height,
right) are used. Both values are summed up and divided by 2. Proceed as
follows:
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Example
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2
Chapter 2 - Sound Sources
2.4.2 RLS-90
•
Click with the right mouse onto the white area of the screen and select
from the context menu the command Modify Objects.
•
On the dialog Modify Objects specify the action „Change Attribute“ for
the object type „Road“ and confirm by OK.
•
On the subsequent dialog select the attribute HBEB, activate
„Arithmetic“ and enter the following expression:
(MEMO_HBEB_L+MEMO_HBEB_R)/2
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2.4.2 RLS-90
•
2 97
When confirming by OK the calculated value is copied to the box „Average Height (m)“ on the dialog Road.
2
Still, the distance between the buildings (DBEB) has to be copied as well.
•
Select from the dialog Modify Attribute the attribute ABST and enter
following formula:
MEMO_DBEB_L + MEMO_DBEB_R
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Chapter 2 - Sound Sources
2.4.2 RLS-90
Now, CadnaA calculates from the entered data the correction for multiple
reflections.
2
As already said, whether the correction for multiple reflections applies or not
depends whether the proportion of gaps is smaller than 30%.
•
In order to consider this in CadnaA, reselect on the dialog Modify
Objects the action Modify Attribute for object type „Road“.
•
On dialog Modify Attribute select the attribute DREFL and enter the
following formula (with option „Replace Strings“):
iif(max(MEMO_LUECK_L,MEMO_LUECK_R)<0.3,DREFL,0)

This expression means in words: If the maximum value of the string
variables MEMO_LUECK_L and MEMO_LUECK_R is smaller than
0.3 (= 30%) keep the value of DREFL, otherwise, replace it by zero (see
also manual „Attributes, Variables, and Keywords“, chapter "Chapter 5
- Operators & Functions").
After confirming the dialog with OK the option „Drefl“ is activated and the
proportion of gaps entered if the condition above is fulfilled. Otherwise,
Drefl= 0 dB and no correction of multiple reflections is applied.
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Chapter 2 - Sound Sources
2.4.2 RLS-90
Using the command Long Straight Road from the context menu of a road
(or from the Extras menu) enables to perform an approximative calculation
of the receiver level along roads complying with the requirements of RLS-90,
section 4.4.1 („infinite long straight road“). This calculation cannot be used in
combination with the other calculation methods from RLS-90 (segmented
road sections).
When selecting the command Long Straight Road a dialog is displayed calculating the sound emission levels LmE,Day and LmE,Night as well as the receiver
levels Lr,Day and Lr,Night. Both receiver levels are calculated when entering the
relevant parameters.
Dialog Long Straight Road (accord. to RLS-90)
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Long Straight Road
2
100
2
Chapter 2 - Sound Sources
2.4.2 RLS-90
The relevant distances and object heights are shown in the following figures.
2
ground plan:
sectional view:
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Chapter 2 - Sound Sources
2.4.2 RLS-90
In case the emission of the road where the context menu command Long
Straight Road has been selected is specified already, the respective emission
levels Lm,E for Day/Night are displayed.
Lm,E Day/Night
2
The calculator symbol enables to alter the emission data via the dialog Road.
Alternatively, after activation of the check box, the emission level Lm,E for
Day/Night can be entered.
In the latter case, the road width or the standard cross section are specified
on the dialog.
Road Width/Standard
Cross Section
The object heights (for road, reflector, obstacle, and receiver point) can be
specified as relative or absolute heights.
relative/absolute Height
Using this form, the height of a barrier (obstacle) can be calculated when a
limiting value has be entered in box „Lr Goal“.
Calculate Height of
Obstacle
Here, the required excess length of the screening obstacle is displayed. This
additional length in direction of the road to both sides - counted from the
perpendiculars of the obstacle to the road line - is required at least in order to
ensure that the calculated receiver levels are met.
Excess Length
Via the button „Save“ the calculation results can be saved and be loaded via
the button „Open“. The file extension used is *.lgs.
Save/Open
The form will be printed using the definitions of the selected template file to
the connected printer.
Print
This button exports the form using the definitions of the selected template
file as a RTF-file, e.g for MS-Word.
Export
A template file can be selected specifying the output format (file suffix *.rtf).
The template files delivered with CadnaA are stored in the directory templates in the CadnaA-installation directory. To create your own template file,
copy an existing template file and alter the text and the format definitions as
required. The variable names can be obtained from the provided template
files.
Template
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Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
2.4.3
Nordic Prediction Method 1996
Two types of evaluation parameters are calculated by the Nordic Prediction
Method (NPM) for road noise (TemaNord 1996:525/73/):
•
the A-weighted equivalent continuous sound pressure level LA,eq and
•
the A-weighted maximum sound pressure level LAFmax.
Further, the number of events NATd/NATn above a threshold level - as prescribed by Swedish law /76/ - can be calculated.
Since the equivalent continuous level LA,eq is calculated per day (24 h) no
specific day- or nighttime values exist in NPM. It is stated, however, that any
other period could be assessed as well using LA,eq provided the traffic data
refers to this period. In contrary, a separate procedure is applied to calculate
the maximum level LAFmax.

2 103
In CadnaA, the emission level LAeq*,10m as shown on the dialog Road
refers to the A-weighted equivalent continuous sound pressure level
LA,eq as emission parameter, corrected for the road surface and for the
road gradient. When calculating the A-weighted maximum sound
pressure level LAFmax the emission parameter shown is still the level
LAeq*,10m.
Dialog Road (for Nordic Prediction Method)
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2
Emission Level LA,eq
2
Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
The A-weighted equivalent continuous sound pressure level LA,eq at 10 m
distance from the road’s axis of an infinite straight road with free sound
propagation calculates from the sound exposure levels for each vehicle
category (light and heavy traffic):
•
level for light traffic:
LAeq ,10 m light   LAE ,10 m light   10 lg
•
N light 
T
dB(A)
level for heavy vehicles (m > 3500 kg):
LAeq ,10 m heavy   LAE ,10 m heavy   10 lg
N heavy 
T
dB(A)
and for both contributions:
LAeq,10 (mixed) = LAeq,10 (light) ++ LAeq,10 (heavy)
where ++ represents the energetic sum.
The sound exposure levels for each category result from:
•
light traffic:
v >= 40 km/h: LAE ,10 m  73.5  25 lg
v
dB(A)
50
30 <= v < 40 km/h: LAE ,10 m  71.1 dB(A)
•
heavy vehicles (m > 3500 kg):
50 km/h <= v <= 90 km/h: LAE ,10  80.5  30 lg v dB(A)
50
30 <= v <= 50 km/h: LAE ,10 m  80.5 dB(A)
and LAE ,10 m v  30 km / h   LAE ,10 m v  30 km / h 
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2.4.3 Nordic Prediction Method 1996
The calculation of the A-weighted maximum sound pressure level LAFmax
makes use of the percentage X% of the vehicles (light & heavy) exceeding
this level (see chapter 6.2.10.2).
Emission Level LAFmax
The arithmetic mean level L AFma x X%,10m due to an exceedance by X% of the
vehicles calculates from equations 2.29 to 2.33 in Part 2 of /73/ using a
numerical approximation of the normal distribution function (to obtain
y(X%) ):
LAFmax X%, 10m
•
2
for light traffic:
v >= 30 km/h: L AFma x X %,10m  69  30 lg v  y  X%   Sigma L ight dB(A)
50
with Sigma Light  5.5  e
0 .7
v
50
dB
and L AFmax,10m  v  30 km / h   L AF max,10m  v  30 km / h 
•
for heavy vehicles (m > 3500 kg):
v > 50 km/h: L AFm ax X %,10m  75  30 lg v  y  X%   Sigma Heavy dB(A)
50
with Sigma Heavy  10  e
v
 0. 9
50
dB
v <= 50 km/h: L AFmax X%,10m  75.0  y  X%   Sigma He avy dB(A)
with Sigma Heavy  4.1 dB
The level LAFmax exceeded by 5% of the vehicles calculates with a factor of
y(5%)=1.64.
Example
When calculating the maximum level the CadnaA protocol still shows the
results for the Leq calculation and thus does not apply.
Protocol with LAFmax
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NATd/NATn
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Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
Swedish law /76/ prescribes to check, besides the maximum level itself,
•
whether a maximum level of 70 dB(A) is exceeded more than 5 times for
each hour during daytime (16 hours, so 16*5=80 exceedances during the
entire daytime), and
•
whether a maximum level of 70 dB(A) is exceeded more than 5 times
within the entire night-time (8 hours), and
•
whether a maximum level of 80 dB(A) is not exceeded at all times.
This evaluation can be achieved by using the evaluation parameters NATd
(for Day) and NATn (for Night), see chapter 6.2.5 "Evaluation Parameters
Tab", and by specifying the length of the Day (16 h) and Night (8 h) periods,
see chapter 6.2.4 "Reference Time Tab". Further, a threshold level has to be
specified on the „Road“ tab (see chapter 6.2.10.2).
As long as traffic count data Day/Night is used (MDTD, N/p%, or diurnal
pattern) the number of events above the entered threshold level NATd/
NATn is calculated from the hourly traffic counts.
 Examples\
02_Sources \Road\
Nordic 96
Results when checking for more than 80
exceedances above 70 dB(A)
during daytime (16 h)
Results when checking for more than 5
exceedances above 70 dB(A)
during night-time (8 h)
NOTE - Consider that the values displayed inside the building evaluation symbol refer to the
first two evaluation parameters (here 1:Ld, 2:Ln, while 3:NATd, 4:NATn).
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Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
The „Mean Daily Traffic Density“ (MDTD, vehicles/24h) does not exist in
NPM as an input parameter for traffic data. Nevertheless, this feature is
provided by CadnaA applying the road types of the Austrian road noise
standards RVS 3.02 /59/ and RVS 4.02 /60/. The respective data is given in
the tables below.
from RVS 4.02, tables 1 and 2:
Attribute Value
STRGATTNR
Road
Type
Day
(6-19 hrs)
Evening
(19-22 hrs)
Night
(22-6 hrs)
N
(veh/h)
p
(%)
N
(veh/h)
p
(%)
N
(veh/h)
p
(%)
2
national
road
0.060 *
MDTD
10
0.036 *
MDTD
15
0.014*
MDTD
25
3
local road
0.064 *
MDTD
10
0.029 *
MDTD
10
0.010 *
MDTD
10
4
main road
0.062 *
MDTD
10
0.035 *
MDTD
5
0.011 *
MDTD
10
5
service
road
0.062 *
MDTD
5
0.041 *
MDTD
2
0.009 *
MDTD
2
from RVS 3.02, tables 1 and 2:
Attribute Value
STRGATTNR
Road Type
Day
(6-22 hrs)
Night
(22-6 hrs)
N
(veh/h)
p
(%)
N
(veh/h)
p
(%)
0
local 3.02
0.065 *
MDTD
10
0.007 *
MDTD
5
1
national 3.02
0.065 *
MDTD
15
0.013 *
MDTD
25
where
N: number of vehicles per hour
p: percentage of heavy vehicles

Speed correction in RVS refers, as it does in NPM, to 50 km/h.
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Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
For the percentage of light/heavy trucks it holds for both (see RVS 3.02, tab.
3 and RVS 4.02, tab. 3):
2
Road Type
Percentage of Heavy Vehicles
light trucks (%)
heavy trucks (%)
national (4.02 & 3.02)
25
75
local (4.02 & 3.02)
90
10
main road
60
40
service road
95
5
Source Geometry
The height entered in the dialog Geometry is the height of the road surface.
The source height is 0.5 m above the road’s center line or above the center
lines of the outer lanes.
Speed Limit (km/h)
According to NPM the real speed is used in the prediction, not the indicated
speed limit. When the real speed is, however, not available the „posted speed“
should be used instead.
Road Surface
In CadnaA, the emission level is corrected with different road surfaces, even
when NPM originally states this correction to be a part of the propagation
model.
The following table lists the types of road surfaces and their respective level
corrections.
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road surface corrections according to NPM, Annex A, Table A1:
Attribute
Value
STRONR
Correction in dB(A) for a certain % of heavy vehicles
Road Surface
0-60 km/h
61-80 km/h
80-130 km/h
0-5
6-19
20-100
0-5
6-19
20-100
0-5
6-100
ref
1
1a Asph.concr. (12-16mm)
ref
ref
ref
ref
ref
ref
ref
2
1b Asph.concr. (12-16mm)
0
0
-1
-2
-1
-1
-2
-2
3
2a Asph.concr. (8-10mm)
0
0
0
-1
0
0
-1
-1
4
2b Asph.concr. (8-10mm)
-1
-1
-1
-2
-1
-1
-2
-2
5
3a Mastic asph. (12-16mm)
0
0
0
1
0
0
1
0
6
3b Mastic asph. (12-16mm)
0
0
0
1
0
0
1
0
7
4a Mastic asph. (8-10mm)
-1
-1
0
-1
-1
-1
-1
-1
8
4b Mastic asph. (8-10mm)
-2
-1
0
-2
-2
-1
-2
-2
9
5 Chipped asphalt (BCS)
1
0
0
2
1
0
2
1
10
6a Chip seal Y1 (16-20mm)
1
0
0
2
1
0
2
1
11
6b Chip seal Y1 (16-20mm)
2
1
0
3
1
0
2
1
12
7a Chip seal Y1 (10-12mm)
0
0
0
0
0
0
0
0
13
7b Chip seal Y1 (10-12mm)
0
0
0
0
0
-1
0
0
14
8a Chip seal Y1 (6-9mm)
0
0
0
-1
0
0
-1
0
15
8b Chip seal Y1 (6-9mm)
-1
0
0
-1
-1
-1
-1
-1
16
9a Chip seal Y2 (16-20mm)
0
0
0
1
0
-1
0
0
17
9b Chip seal Y2 (16-20mm)
1
0
0
1
0
-2
0
0
18
10a Chip seal Y2 (10-12mm)
0
0
0
0
0
-1
0
-1
19
10b Chip seal Y2 (10-12mm)
0
0
0
0
-1
-2
0
-1
20
11a Porous asph. (14-16mm)
0
0
0
-1
-1
-1
-1
-1
21
11b Porous asph. (14-16mm)
--1
-1
0
-1
-1
-1
-1
-2
22
11c Porous asph. (14-16mm)
-2
-2
-2
-2
-2
-3
-2
-3
23
12a Porous asph. (8-12mm)
0
0
0
-1
-1
-1
-2
-2
24
12b Porous asph. (8-12mm)
-1
-1
-1
-2
-2
-2
-3
-3
25
12c Porous asph. (8-12mm)
-3
-3
-3
-4
-4
-5
-5
-5
26
13 Cem.concr. (20-80mm)
2
1
1
2
2
2
2
2
27
14 Cem.concr. (12-18mm)
1
1
1
2
2
2
2
2
28
15 Cem.concr.,ground
-1
-1
-1
-2
-2
-2
-1
-1
29
16 Paving Stones
3
3
2
5
4
3
5
4
30
17 Cement block pavement
0
0
0
0
0
0
0
0
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2
Gradient (%)
2
Chapter 2 - Sound Sources
2.4.3 Nordic Prediction Method 1996
In CadnaA, a varying road gradient corrects the emission level already, even
when NPM originally states this correction to be a part of the propagation
model.
The correction for the road gradient Lst (in dB) results from:
Lst 
2G 3G

lg1  p 
100 100
where
G: gradient in %o (10%o =1%)
p: proportion of heavy vehicles (in %)
In CadnaA, the road gradient is specified in % instead.

Correction for
Multiple Reflections
When calculating the A-weighted maximum sound pressure level LAFmax no gradient correction is applied (even not when option „Road Gradient: auto“ is selected.
NPM provides an overall correction for multiple reflection in side streets
where the noise impact results from a main street (section 2.6.9 of part 2 of /
73/). As this correction alters the normal distance correction it is part of the
propagation model and, thus, not part of the emission model. However, the
correction Lms can be entered manually on the dialog Road, for parameter
„Drefl“, with activating the configuration option „Calc exactly one Reflection
Order“ (see chapter 6.2.10.2). When applying the correction for multiple
reflections the maximum number of reflections calculated using image
sources should be restricted to the first order.
When the option „Average Height“ is selected (with option „Calc exactly one
Reflection Order“ still activated) the correction for multiple reflections is
calculated from the average height, the distance and the reflecting properties
of the buildings according to RLS-90 (see chapter 2.4.2, section "Correction
for Multiple Reflections").
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2.4.4
2 111
NMPB-Routes 1996
The emission parameter in NMPB-1996 („Nouvelle Méthode de Prévision
du Bruit“) is the A-weighted sound power level per octave band LAw,i of a
point-like sub-source Si in dB(A) /77/. This level calculates from:


LAw,i  10 lg 10 EVL 10 lg QVL /10  10 EPL 10 lg QPL /10  20 dB  10 lg li  Ri 
where
EVL: sound power level of the light vehicles, in dB(A)
QVL: traffic number of the light vehicles (max. mass m < 3500 kg), in veh/h
EPL: sound power level of the heavy vehicles, in dB(A)
QPL: traffic number of the heavy vehicles (max. mass m >= 3500 kg), in veh/h
li: length of the sub-source Si, in m
R(i): octave values of the reference spectrum for road noise, in dB(A)
i: running number of octave
In CadnaA, the overall traffic flow Q (in vehicles/hour) and the percentage
of heavy vehicles p% is to be specified instead. The relation between those
figures and the ones above are:
Q  QVL  QPL and p% 
QPL
Q
Dialog Road (for NMPB 96)
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2
Emission Parameter LwA’
2
Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
The emission parameter displayed on the dialog Road is A-weighted total
sound power level per unit length L’Aw,i in dB(A) according to the modified
equation:


L' Aw,i  10 lg 10 EVL 10 lg QVL  / 10  10 E PL 10 lg QPL  / 10  20 dB   in dB(A)

Reference Spectrum
This value includes the correction for the vehicle type, the type of traffic flow, the correction of road gradient and the road surface correction
 (see below).
The values R(i) of the weighting spectrum are listed in the following table:
i
Frequency
(Hz)
R(i) in
dB(A)
1
125
-14
2
250
-10
3
500
-7
4
1000
-4
5
2000
-7
6
4000
-12
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Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
The emission level E is taken from the following diagram:
Emission Level E
2
Diagram for NMPB-specific emission parameter E (approximative)
Legend (road gradient g%):
Horizontal
(-2% < g < 2%)
Monté
(g > 2%)
Descente
(g < -2%)
Fluide continu
1.1
1.2
1.3
Pulsé non différencié
2.1
2.2
2.3
Accéléré
3.1
3.2
3.3
Décéléré
4.1
4.2
4.3
This diagram considers:
•
•
•
•
two types of vehicles (light and heavy)
four types of traffic flows (fluide continu, pulsé non différencié, accéléré,
décéléré),
three types of road gradient (horizontal, montée, descente) and
the traffic speed for light and heavy vehicles.
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2
MDTD
2
Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
The „Mean Daily Traffic Density“ (MDTD, vehicles/24h) does not exist in
NMPB as an input parameter for traffic data. Nevertheless, this feature is
provided by CadnaA applying the road types of the German road noise standard RLS-90 /15/ in conjunction with VBUS /115/. The respective data for
the hourly traffic data M (veh/h) and the truck proportion p (%) is given in
the next table.
Attribute Value
STRGATTNR
Road
Type
Day
(6-18 h)
Evening
(18-22 h)
Night
(22-6 h)
Q
(veh/h)
p
(%)
Q
(veh/h)
p
(%)
Q
(veh/h)
p
(%)
0
Motorway
0.062 *
MDTD
25
0.042 *
MDTD
35
0.014 *
MDTD
45
1
Federal
Road
0.062 *
MDTD
20
0.042 *
MDTD
20
0.011 *
MDTD
20
2
Ordinary
Road
0.062 *
MDTD
20
0.042 *
MDTD
15
0.008 *
MDTD
10
3
Local
Road
0.062 *
MDTD
10
0.042 *
MDTD
6.5
0.011 *
MDTD
3
Source Geometry
The height entered in the dialog Geometry is the height of the road’s surface.
The source height is 0.5 m above the road’s center line or above of the center
lines of the outer lanes.
Speed Limit (km/h)
The minimum speed according to NMPB is 20 km/h for all types of vehicles.
The maximum speeds are 140 km/h for autos and 100 km/h for trucks. For
higher speeds a speed of 140 km/h for autos and of 100 km/for trucks is
used. In case a speed below 20 km/h is entered, 20 km/h is applied instead.
Road Surface
With NMPB, the correction for different road surfaces is already included in
the emission level E. By default, the road surfaces listed in the following table
are available (types „EC“ resulting from /114/).
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Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
Attribute
Value
STRONR
Road Surface
road surface correction  in dB
at a speed of
Spectrum
Type
applied
<= 60
km/h
<= 100 km/h
EC: <= 80 km/
h
1
Enrobé bitumé
1
2
Enrobé drainant
2
3
Chaussée cloutée
1
2
4
Béton lisse
1
0
5
Béton strié
1
3
6
Pavés (en ville)
1
3
101
EC: Porous surface
1
102
EC: Smooth asphalt
1
0
103
EC: Cement concrete
1
2
104
EC: Smooth texture Paving
1
3
105
EC: Rough texture Paving
1
6
0-3,5 *)
-1
-2
spectrum type 1: road spectrum (see previous section „Reference Spectrum“)
spectrum type 2: spectrum for „Enrobé drainant“ (see below)
*) correction linearly increasing from 0 dB for 50 to 3,5 dB for 100 km/h
Spectrum for road surface „Enrobé drainant“ (for  = 3,5 dB(A)):
i
Frequency (Hz)
R(j) in dB(A)
1
125
0
2
250
0
3
500
0,5
4
1000
5,5
5
2000
7
6
4000
7
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<= 130
km/h
0
0
2 115
3,5
-3
116
2
User-defined Road
Surfaces
2
Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
With NMPB selected, additional road surfaces can be defined by the user.
Open the local library for sound reduction indices (menu Tables|Libraries
(local)|Sound Reduction Indices) and enter a new line via the table’s context menu. For a sound reduction index spectrum to be selectable as a road
surface correction, the ID has to start with the text sequence: NMPB_X,
where X is an integer without a leading zero (for example: NMPB_1, NMPB_11, NMPB_111, but not NMPB_01). The entered name will be shown at
the end of the default list of road surfaces.
Example: user-defined road surface spectrum
Traffic Flow
The selected type of traffic flow applies to all daily periods D/E/N. Available
types are:
•
•
•
•
Button DEN
fluide continu
pulsé non différencié
accéléré
décéléré
Clicking this button enables to define different types of traffic flow for the
time periods Day|Evening|Night.
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The road gradient can be entered in % or be calculated automatically,
depending on the z-heights of the road.
Gradient (%)
2
For information on the different options offered in the list box „Road
Gradient“ of the dialog Road see chapter 2.4.1 "Common Input Data", section "Road Gradient (%)", for details.
There is no global correction available in NMPB-96 to correct for multiple
reflections. However, CadnaA enables to restrict the calculation using image
sources to the 1st order of reflection and to correct for multiple reflections
according to RLS-90 /17/.
see chapter 6.2.10.3 "NMPB-Routes 1996" and chapter 2.4.2 "RLS-90"
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Chapter 2 - Sound Sources
2.4.4 NMPB-Routes 1996
2
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2.4.5 NMPB-Routes 2008
2.4.5
2 119
NMPB-Routes 2008
The emission parameter in NMPB-2008 /78/ is the A-weighted third-octave
sound power level per unit length and per vehicle in dB(A). This level
calculates from /79/:


LW / m  j   10 lg 10 LW / m / VL 10 lg QVL  /10  10  LW / m / PL 10 lg QPL  /10  R  j 
where
LW/m/VL: sound power level per unit length of the light vehicles, in dB(A)
QVL: hourly traffic of the light vehicles (max. mass m < 3500 kg), in veh/h
LW/m/PL: sound power level per unit length of the heavy vehicles, in dB(A)
QPL: hourly traffic of the heavy vehicles (max. mass m >= 3500 kg), in veh/h
R(j): third-octave values of the reference spectrum for road noise, in dB(A)
j: running number of octave
In CadnaA, the overall traffic flow Q (in vehicles/hour) and the percentage
of heavy vehicles p% is to be specified instead. The relation between those
figures and the ones above are:
Q  QVL  QPL and p% 
QPL
Q
Dialog Road (for NMPB 2008)
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2
Emission Parameter LwA’
2
Chapter 2 - Sound Sources
2.4.5 NMPB-Routes 2008
The emission parameter displayed on the dialog Road is the A-weighted total
sound power level per unit length L’Aw in dB(A) according to:
18
L'wA  j   10 lg 100.1LW / m  j  in dB(A)
j 1
In this case, always the emission spectrum for non-porous surfaces is used.
Traffic Data
The noise emission is calculated from traffic data based on the daily periods
Day (6-18 h) and Night (22-6 h). The day may be subdivided into two further
periods: 6-18 h (Day) and 18-22 h (Evening). The emission is estimated
according the following specifications depending on:
•
•
•
the „Mean Daily Traffic Density“ (MDTD, veh/24h) or „Annual Average
Daily Traffic“ (AADT, veh/24h) or the „trafics moyens journaliers annuels“ (TMJA, veh/24 h),
the daily time period,
the number of lanes (for urban and inter-urban roads).
In any case, the emission is limited to the emission caused by a so-called
„maximum traffic flow“ situation („émission sonore maximale du flot“).
MDTD (TMJA)
Specifying the MDTD or TMJA calculates the emission level depending on
the road type selected. NMPB 2008, table 2.1, specifies TMJA-ranges in
combination with ranges of the percentage of heavy vehicles %PL:
Road Type
Voiries
structurantes
urbaines
Voiries
urbaines
intersecteurs
Voiries
urbaines de
secteurs
TMJA
%PL
%HPS
veh/day
daytime
(6-22 h)
nighttime
(22-6 h)
17000 to
217000
5 to 20%
5 to 35%
2500 to
25000
(Île-deFrance:
50000)
0 to 5%
%TV
daytime
7,5 to 9,5
6,5 to 9,5
%TV
nighttime
-
85 to 95%
15 to 5%
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The following road types are available:
•
•
Road Types
road types from the German VBUS /115/ are taken instead in CadnaA
(see chapter 2.4.2 "RLS-90", section "MDTD - VBUS"), and
road types from NMPB 2008 /79/:
Average hourly Flow Rate per Daily Period (veh/h)
Road Type
6 - 18 h
18 - 22 h
22 - 6 h
Motorway long distance
TMJA/17
TMJA/19
TMJA/82
Motorway regional
TMJA/17
TMJA/18
TMJA/100
Intercity long distance
TMJA/17
TMJA/19
TMJA/110
TMJA/17
TMJA/19
TMJA/120
Intercity regional
Average hourly Flow Rate for PL (HGV) per Daily Period (veh/h)
Road Type
6 - 18 h
18 - 22 h
22 - 6 h
Motorway long distance
TMJA/20
TMJA/20
TMJA/39
Motorway regional
TMJA/17
TMJA/28
TMJA/50
Intercity long distance
TMJA/17
TMJA/27
TMJA/51
Intercity regional
TMJA/17
TMJA/34
TMJA/73
This results in the following total number of vehicles per hour Q and
percentage of heavy vehicles p%:
total number of vehicles per hour Q per Daily Period (veh/h) *)
Road Type
6 - 18 h
18 - 22 h
22 - 6 h
Motorway long distance
0.109 TMJA
0.103 TMJA
0.038 TMJA
Motorway regional
0.118 TMJA
0.091 TMJA
0.030 TMJA
Intercity long distance
0.118 TMJA
0.090 TMJA
0.029 TMJA
Intercity regional
0.121 TMJA
0.082 TMJA
0.022 TMJA
percentage of heavy vehicles p% per Daily Period
Road Type
6 - 18 h
18 - 22 h
22 - 6 h
Motorway long distance
45.9
48.7
67.8
Motorway regional
50.0
39.1
66.7
Intercity long distance
50.0
41.3
68.3
Intercity regional
51.5
35.8
62.2
*) Factors rounded to third decimal, while CadnaA is using full precision.
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2.4.5 NMPB-Routes 2008
The maximum speed is 130 km/h for autos, and 100 km/h for trucks.
Speed Correction
NMPB 2008 states that the speed of autos is equivalent to the indicated maximum speed of a road while the maximum speed of trucks are depending on
road type. In CadnaA, however, the speed of trucks has to edited by the user
as these road types do not combine with the road types used for MDTD/
TMJA.
2
Road Type
Speed of Trucks PL (km/h)
highway interconnection
90
speed lane, urban
90
road with separated carriage ways
85
road with single carriage ways
80
in agglomerations
indicated speed
The values R(j) of the weighting spectrum are listed in the following table:
Reference Spectrum
third-octave band center
frequency (Hz)
100
125
160
200
250
315
400
500
630
porous surfaces
-22
-22
-20
-17
-15
-12
-10
-8
-9
non-porous surfaces
-27
-26
-24
-21
-19
-16
-14
-11
-11
third-octave band center
frequency (Hz)
800
1000
1250
1600
2000
2500
3150
4000
5000
porous surfaces
-9
-10
-11
-12
-13
-16
-18
-20
-23
non-porous surfaces
-8
-7
-8
-10
-13
-16
-18
-21
-23
Source Description
For each vehicle category, the emission (sound power level per unit length)
consists of two components:

LW / m / veh  10 lg 10
0.1Lr_ W / m
0.1 Lm_ W / m
 10

where
Lr_W/m: rolling noise, due to tire-road interaction, called „roll noise“
Lm_W/m: mechanical sources of the vehicles, called „engine noise“
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The roll noise component for three types of road surface (R1, R2, R3) is given in the next table („average emission for an aged surface less than ten years
old“):
Attribute Value
STRONR
Road Surface
Category
Speed Range v (km/h)
Autos (VL)
Speed Range v (km/h)
Trucks (PL)
LWA’ (dBA/m)
(20 <= v <= 130)
LWA’ (dBA/m)
(20 <= v <= 100)
1
Revêtement R1
53,4 + 21 log (v/90)
61,5 + 20 log (v/80)
2
Revêtement R2
55,4 + 20,1 log (v/90)
63,4 + 20 log (v/80)
3
Revêtement R3
57,5 + 21,4 log (v/90)
64,2 + 20 log (v/80)
4
Revêtement R1
drainant
as for Revêtement R1
as for Revêtement R1
5
Revêtement R2
drainant
as for Revêtement R2
as for Revêtement R2
6
Revêtement R3
drainant
as for Revêtement R3
as for Revêtement R3
Regarding the roll noise component the following comments apply:
•
Porous and non-porous surfaces have the same speed correction,
however, a different spectrum is used (see section "Reference Spectrum").
•
By the three surface categories R1 to R3 several road surface types are
grouped. For examples see NMPB-2008, section 2.7.2.1.
•
The road surface categories „Revêtement R2 drainant“ and „Revêtement
R3 drainant“ are not listed in NMPB 2008, but have been introduced in
CadnaA based on French user requests.
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2
Age of Road Surface
Chapter 2 - Sound Sources
2.4.5 NMPB-Routes 2008
NMPB-2008 corrects for the deterioration of the road surface with time as
specified by the table below (with a: age of road surface in years):
2
Road Surface
Category
VL (light vehicles)
PL (heavy goods vehicles)
<= 2 years
2 to 10 years
<= 2 years
2 to 10 years
-4
0.5*(a - 10)
-2.4
0.3*(a - 10)
R2
-2
0.25*(a - 10)
-1.2
0.15*(a - 10)
R3
-1.6
0.2*(a - 10)
-1
0.12*(a - 10)
R1
The „Year of Construction of Surface“ is specified on each dialog Road while
the „Year of Calculation“ is specified on the dialog Configuration, „Road“
tab, with NMPB-2008 selected (see chapter 6.2.10.4 "NMPB-Routes 2008").

Engine Noise
Since the road surface definition in NMPB 2008 applies different speed
corrections for Autos and Trucks, combined with an even more
complex scheme for aging, it is not possible - in opposite to NMPB
1996 (see chapter 2.4.4) - to enter user-defined road surfaces in
CadnaA.
With engine noise the following effects influence the radiated noise:
•
•
traffic flow condition, five different situations apply:
 stabilisée,
 accélération,
 décélération,
 troncons de démarrage,
 troncons d'arrêt.
road gradient, three different situations apply:
 horizontal (gradient <= 2% absolute),
 increasing (gradient 2 to 6%),
 decreasing (gradient -2 to -6%)
Gradients larger to 6% (absolute) do not increase the correction.

For the time being, the respective equations for all engine noise
situations are not stated here.
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2.4.5 NMPB-Routes 2008
The height entered in the dialog Geometry is the height of the road’s surface.
The source height is 0.05 m above the road’s center line or above of the center lines of the outer lanes.
Source Geometry
The selected type of traffic flow applies to all daily periods D/E/N. Available
types are:
Traffic Flow
•
•
•
•
•
2
stabilisée
accélération
décélération
troncons de démarrage
troncons d'arrêt
Clicking this button enables to define different types of traffic flow for the
time periods Day|Evening|Night.
Button DEN
There is no global correction available in NMPB-2008 to correct for multiple
reflections. However, CadnaA enables to restrict the calculation using image
sources to the 1st order of reflection and to correct for multiple reflections
according to RLS-90 /17/.
Correction for
Multiple Reflections
see chapter 6.2.10.4 "NMPB-Routes 2008" and chapter 2.4.2 "RLS-90"
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Chapter 2 - Sound Sources
2.4.5 NMPB-Routes 2008
2
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2.4.6 CNOSSOS-EU (Road)
2.4.6
2 127
CNOSSOS-EU (Road)
The emission parameter in CNOSSOS-EU /16/ is the A-weighted longterm average sound pressure level for Day, Evening and Night period,
computed by summation over all frequencies:
L Aeq,LT  10  lg 10
Le q ,T ,i Ai 
i 1
dB  A
where
Ai: A-weighting correction according to IEC 61672-1
i: frequency band index (octaves 125 to 4000 Hz)
T: time period corresponding to Day, Evening or Night
Assuming a steady traffic flow of Qm vehicles of category m per hour is
assumed, with an average speed vm (in km/h), the sound power per metre in
frequency band i of the source line LW', eq,line,i,m is defined by:
 Qm

L W',e q,line,i,m  L W,i ,m  10  lg 

 1000  vm 
where LW,i,m is the directional sound power of a single vehicle (re. 10-12 W/m)
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2
Vehicle Categories
2
Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
Traffic flow Qm is expressed as yearly average per hour, per time period (Day,
Evening, Night), for the following vehicle categories:
Category
m
Name
Description
1
Light motor
vehicles
Passenger cars, delivery vans <= 3.5 tons, SUVs, MPVs
including trailers and caravans
2
Medium
heavy vehicles
Medium heavy vehicles, delivery vans > 3.5 tons, buses,
motorhomes, etc. with two axles and twin tyre mounting on
rear axle
3
Heavy
vehicles
Heavy duty vehicles, touring cars, buses, with three or more
axles
4a
Powered twowheelers
Two-, Three- and Four-wheel Mopeds
4b
Motorcycles with and without sidecars, Tricycles and
Quadricycles
The following traffic amount formula and attributes apply to the respective
input boxes on the Road dialog (see also section "Exact Counts"):
Input Box
Amount formula
from categories m
CadnaA
Attributes
Number of Vehicles/Hour
1+2+3+4
Percentage heavy vehicles 2+3 (%)
(2+3)/(1+2+3+4)*100%
Heavy Trucks 3 in 2+3 (%)
3/(2+3)*100%
PLT, PLE, PLN
Motorcycles 4a+4b (%)
(4a+4b)/(1+2+3+4)*100%
PSLAT, PSLAE,
PSLAN
Motorcycles 4b in 4a+4b (%)
4b/(4a+4b)*100%
PLLAT, PLLAE,
PLLAN
MT, ME, MN
PT, PE, PN
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2.4.6 CNOSSOS-EU (Road)
The calculation of emission considers two main noise source types:
•
•
Source Types
rolling noise due to the tire-road interaction (while aerodynamic noise is
incorporated in the rolling noise source).
propulsion noise produced by the drive line (engine, exhaust, etc.) of the
vehicle.
2
For light, medium and heavy motor vehicles (categories 1, 2 and 3), the total
sound power corresponds to the energetic sum of the rolling and the propulsion noise. For two-wheelers (category 4), only propulsion noise is considered. For all categories, with speeds less than 20 km/h the sound power level
as for vm=20 km/h is used.
The emission by rolling noise is described by the sound power level in the
frequency band i per vehicle of class m=1, 2 or 3:
 v
L WR ,i,m  AR ,i ,m  BR,i, m  lg  m
 vref
Rolling Noise

   LWR ,i ,m

with L WR,i,m   L WR ,road,i,m  L studdded tyres,i,m  L WR,acc ,i ,m  L W,temp
The coefficients AR,i,m and BR,i,m are given in octave bands for each vehicle
category and for a reference speed vref = 70 km/h (see /16/ for details).
LWR,i,m
is the sum of the following corrections for rolling noise:
Correction
accounts for the effect on rolling
noise ...
frequency
dependent
LWR,road,i,m
by road surfaces different from the
virtual reference surface
yes
for details see below in this chapter
Lstudded tyres,i,m
by studded tyres with light vehicles
(category 1)
yes
enter period and percentage on the
„Road“ tab, see chapter 6.2.10.5
LWR,acc,i,m
by crossings with traffic lights or
roundabouts
no
for details see chapter 2.5 "Crossings
with Traffic Lights"
LW,temp
by the temperature T different from
Tref = 20°C
yes
see chapter 6.2.10.5
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2
Propulsion Noise
2
Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
The propulsion noise emission includes all contributions from engine,
exhaust, gears, air intake, etc. The propulsion noise sound power level in the
frequency band i for a vehicle of class m is:
 v  vre f
L WP ,i, m  AP,i,m  BP,i,m   m
 vref

  L WP,i,m

with L WP,i,m   L WP ,road,i,m  L WP,grad,i,m  L WP,acc,i,m
The coefficients AP,i,m and BP,i,m are given in octave bands for each vehicle
category and for a reference speed vref = 70 km/h.
LWP,i,m
is the sum of the following corrections for propulsion noise:
Correction
accounts for the effect on
propulsion noise ...
frequency
dependent
Remarks
LWP,road,i,m
by different road surfaces due to sound
absorption
yes
for details see below in this chapter
LWP,grad,i,m
by road gradients
no
for details see below in this chapter
LWP,acc,i,m
by accelerating and decelerating
vehicles at intersections
no
for details see chapter 2.5 "Crossings
with Traffic Lights"
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Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
Specification of
Emission
The specification of traffic counts using MDTD („Mean Daily Traffic
Density“, vehicles/24h) in conjunction with a road type does not exist in
CNOSSOS-EU as an input parameter for traffic data. Nevertheless, this feature is available in CadnaA by applying the road types and traffic counts as
specified by the Austrian road noise standards RVS 3.02 /59/ and RVS 4.02
/60/ respectively (see chapter 2.4.3, section "MDTD").
Counts, MDTD
This option enables to enter counts and percentages for the five CNOSSOSspecific vehicle classes.
Exact Counts
Note that the „Number of Vehicles/hour“ addresses the total amount for all
classes and the „Percentage heavy vehicles 2+3 (%)“ and the „Percentage
Motorcycles 4a+4b (%)“ refer to that amount, whilst „Percentage Trucks 3 in
2+3 (%)“ and „Percentage Motorcycles 4b in 4a+4b (%)“ refer to the both
above percentages being assumed as 100%.
Example:
Percentage Trucks 3 in 2+3 = 50%, for Day: 50% of 15% gives 7.5%,
resulting in 7.5% vehicles in each of classes 2 and 3
Percentage Motorcycles 4a+4b =0%: no motorcycles in 4a and 4b
The emission data for vehicle categories 1, 2, 3, 4a and 4b can be edited in the
configuration (see chapter 6.2.10.5, section "Vehicle Classes").
direct input of L‘wA in dB(A)
LwA‘ dB(A)
see chapter 2.4.1 "Common Input Data", section "Diurnal Pattern"
Diurnal Pattern
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2
Source Geometry
2
Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
In CNOSSOS-EU, a road with multiple lanes can be replaced in the
calculation alternatively:
1.
by a number of source lines placed in the centre of each lane, or
2.
by a single source line in the middle of a two way road, or
3.
by one source line per carriageway in the outer lane of multi-lane roads.
In CadnaA, alternative 3 is applied by default.
In order to use alternative 1 enter as many parallel road objects as there are
lanes, each road object having a road width of 0 m (causing a single emission
line in each case). In order to apply alternative 2, deactivate the option
„Calculate outer Lanes separately“ on the „Road“ tab (see chapter 6.2.10.5).
The line source/s is/are segmented with each segment being replaced by a
point source. The source height is 0.05 m above the road surface for all
vehicle classes 1 to 4. The height entered in the dialog Geometry is the
height of the road surface.
Speed Correction
Traffic speed can be specified for "Autos" and - if activated - for "Trucks"
separately (in km/h). The speed limit entered for "Autos" will be considered
for autos and motorcycles while the speed limit entered for "Trucks" - if any
- will be considered for medium and heavy trucks. With the limit entered just
for "Autos" (i.e. option "Trucks" deactivated) the value applies to all types of
vehicles (i.e. no intrinsic speed limit for trucks).
Consequently, there is no road-specific speed limit for motorcycles. However,
a vehicle class specific speed limit for motorcycles can be entered on the
„Road“ tab (see chapter 6.2.10.5).
Button DEN
see chapter 2.4.1, section "Button DEN"
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Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
The effect of road gradient is considered in the propulsion noise only, where
a steady speed is assumed. The correction term LWP,grad,m is a function of
the slope s%, the vehicle speed vm (in km/h) and the vehicle class m. In the
case of a bi-directional traffic flow, it is necessary to split the flow into two
components and correct half for uphill and half for downhill. The same
correction term is attributed to all octave bands.
Road Gradient (%)
2
The equations used for gradient correction are not reproduced here. Instead,
the subsequent diagrams show the range of the correction term LWP,grad,m
depending on road gradient s% and on the vehicle‘s speed (in km/h) for vehicle categories m=1, 2 and 3. For vehicle category m=4 („powered twowheelers“) the correction LWP,grad,m=4 is zero at all speeds and gradients.
When entering the road gradient manually the gradient correction is added to
the emission value L‘WA.
Road Gradient: Input (%)
Note that, while the gradient correction itself is not frequency dependent, the
resulting emission spectrum of the road segment will change anyway
depending on the actual traffic mix due to different emission spectra per
vehicle category.
When using these options (see chapter 2.4.1, section "Road Gradient (%)")
the gradient correction is not added to the emission value, but considered
within the calculation. In this case, the gradient correction will be listed on
the protocol (see chapter 6.5).
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2
2
Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
Vehicle Cat. 1:
Light motor
vehicles
20
18
) 16
B
(d
1
= 14
m
,
d
ar
g, 12
P
W
La
tl
e 10
D
n
o
it
c 8
e
rr
o
c
t
n 6
e
i
d
ar
g
4
20
40
60
80
100
120
2
0
‐20
‐16
‐12
‐8
‐4
0
4
8
12
16
20
gradient s%
Vehicle Cat. 2:
Medium heavy
vehicles
20
18
16
)
B
d
(
2
=
,m
d
ar
,g
P
LW
at
l
e
D
n
o
it
c
re
r
o
c
t
n
ie
ad
rg
14
12
20
40
10
60
80
8
100
120
6
4
2
0
‐20
‐16
‐12
‐8
‐4
0
4
8
12
16
20
gradient s%
Vehicle Cat. 3:
Heavy vehicles
20
18
) 16
B
d
(
3
= 14
,m
d
ar
,g 12
P
W
La
tl
e 10
D
n
o
it
c 8
e
rr
co
t
n 6
ie
d
ar
g
4
20
40
60
80
100
120
2
0
‐20
‐16
‐12
‐8
‐4
0
4
8
12
16
20
gradient s%
Correction for road gradient LWP,grad for vehicle categories m=1, 2, 3
and for speeds v = (20, 40, 60, 80, 100, 120) km/h
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Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
This list box enables to select a road surface from the local or global library
(). If records exist in the local library, they are displayed at the top of the list.
Road Surface
2
gives access to the global library of road surfaces
The road surface correction term for the rolling noise emission is:
v 
L WR,road,i,m   i,m   m  lg  m  dB
 v ref 
where
i, m is the spectral correction in dB at reference speed vref for category m (1, 2 or 3) and spectral band i,
m is the speed effect on the rolling noise reduction for category m (1, 2 or 3) and is identical for
all frequency bands.
The road surface correction term for the propulsion noise emission is:
L WP,road,i,m  min   i,m ;0  dB
This means that absorbing surfaces decrease the propulsion noise, while nonabsorbing surfaces do not increase it.

The road surface correction for the „reference road surface“ (see
below) is zero for all octaves and for all vehicle categories.
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Chapter 2 - Sound Sources
2.4.6 CNOSSOS-EU (Road)
The following CNOSSOS-specific road surfaces are available:
2
Attribute Value
STRO_ID
Road Surface Description
Validity Range *1)
Min. speed
[km/h]
Max. speed
[km/h]
-
-
CNS_01
Reference road surface *2)
CNS_02
1-layer ZOAB (very porous asphalt)
50
130
CNS_03
2-layer ZOAB
50
130
CNS_04
2-layer ZOAB (fine)
80
130
CNS_05
SMA-NL5 (stone mastic asphalt)
40
80
CNS_06
SMA-NL8
40
80
CNS_07
Brushed down concrete
70
120
CNS_08
Optimized brushed down concrete
70
80
CNS_09
Fine broomed concrete
70
120
CNS_10
Worked surface
50
130
CNS_11
Hard elements in herring-bone (e.g. made
of prefabricated concrete or clay blocks)
30
60
CNS_12
Hard elements not in herring-bone
30
60
CNS_13
Quiet hard elements
30
60
CNS_14
Thin layer A
40
130
CNS_15
Thin layer B
40
130
*1) CNOSSOS-EU does not specify how to handle speeds lower the listed minimum speeds, but
higher than the general lower speed limit of 20 km/h. In the same way, it does not specify how to
handle speeds higher the listed maximum speeds. In CadnaA, therefore, the road surface corrections are applied irrespective of the speed for the time being.
*2) „The reference road surface is considered to be a virtual road surface, consisting of an
average of dense asphalt concrete 0/11 and stone mastic asphalt 0/11, between 2 and 7 years old
and in a representative maintenance condition.“ (cited from CNOSSOS-EU)

Further national road surfaces available in CadnaA will not get
documented here.
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Chapter 2 - Sound Sources
2.4.7 CRTN
2.4.7
2 137
CRTN
The evaluation parameter in CRTN („Calculation of Road Traffic Noise“) is
the level L10 (for 18 hours) in dB(A) which is defined based on the level L10
hourly in dB(A) /81/. The level L10 (1h) is the level just exceeded in 10% of
the time within one hour. The L10 (18h) is the arithmetic average of all values
L10 (1h) between 6:00 and 24:00 hours (total 18 values).
The emission parameter L10 is calculated from the following equations depending on what option for „Emission“ is selected:
L10 (1h)  42.2  10 lg q or L10 (18h)  29.1  10 lg Q in dB(A)
where the number of vehicles per hour q calculates from the 18h-count Q
(see CRTN, charts 2 and 3):
q  10

13.1
10
* Q or approximately q  Q / 20.417 .
This assumes a basic speed of v=75 km/h, a percentage of heavy vehicles
(HGV) of p%=0, and a road gradient of G=0%.

For the low traffic correction see chapter 6.2.10.6.
Dialog Road (for CRTN)
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Emission Parameter
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2
Option „Motorway“
(marked by a red frame)
2
Chapter 2 - Sound Sources
2.4.7 CRTN
This option is displayed only if „Leq acc. to Annex A Method 1 of TRL
study“ is selected on the „Road“ tab (see chapter 6.2.10.6).
Specification of
Emission
MDTD & Road Type
The „Mean Daily Traffic Density“ (MDTD, vehicles/24h) does not exist in
CRTN as an input parameter. Nevertheless, this feature is provided by CadnaA offering two options (see list box „Road Type“ on dialog Road):
1.
Specification of the percentage of heavy goods vehicles (HGV, with an
unladen mass > 1525 kg) in the range from 0% to 95%, applying the
equation for q (as above). In this case, the resulting emission levels L10
are equal for all three daily time periods D/E/N.

The attribute STRGATT enables to switch between different settings
for the proportion of heavy vehicles by using the following string
(where xx represents the proportion of heavy vehicles as a available
from the list box „Road Type“): HGVxx (e.g. HGV50)
2.
Specification of one of the road types from the German road noise
standard RLS-90 /15/. The respective data for the hourly traffic data q
(veh/h) and the truck proportion p(%) is given in the next table. In this
case, the hourly count q for Day calculates from the 18h-count Q as
specified by CRTN while for Night the distribution in RLS-90 is used.
Thus, just the daytime level is in accordance with CRTN.
Attribute Value
STRGATTNR
Road Type
Day
(6-22 h)
Night
(22-6 h)
q
(veh/h)
p
(%)
q
(veh/h)
p
(%)
0
Motorway
q  Q / 20.417
25
0.014 Q
45
1
Federal Road
q  Q / 20.417
20
0.011 Q
20
2
Ordinary Road
q  Q / 20.417
20
0.008 Q
10
3
Local Road
q  Q / 20.417
10
0.011 Q
3
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Chapter 2 - Sound Sources
2.4.7 CRTN
This option enables to enter hourly traffic data q and percentage of heavy vehicles p% for the three time periods Day/Evening/Night.

Exact Count Data
2
This data can also be imported via ODBC (see chapter 7.3).
The emission level L10 can be entered directly. In this case, the corrections
(for speed, road type etc.) are not applied.
Specifying L10
Furthermore, diurnal patterns can be used in CadnaA to specify road
emission. Diurnal patterns are introduced via the local libraries on the Tables
menu.
Diurnal Patterns
Diurnal Pattern
Subsequently, the ID of the pattern will be available from the lower end of
the list box „Road Type“ on the dialog Road.
As long as the option "Use Non Standard Reference Time D/E/N" on
dialog Calculation|Configuration, tab „Road“, is deactivated the data from
6 to 24 hours of the selected pattern will be used to calculate the level L10
(i.e. ignoring the traffic figures from 0 to 6 hours).

In this case, the figures displayed for the hourly traffic q are not correct
as they refer to the entire pattern (from 0 to 24 hours).
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2
Chapter 2 - Sound Sources
2.4.7 CRTN
With counts Q being 0 (Zero) the pattern will be used as entered for
calculation of emission. When entering a value for Qentered the hourly values
qapplied of the pattern will be corrected according to:
q applied  Qentered (18h) *
q pattern
Q pattern , 6  24 h (18h)
For the pattern above the result for L10,18h (displayed for D, while results
for E and N not being relevant) will be the same when entering 18000 for Q
results as with entering 0 (Zero). Entering the half amount (9000/18 h) will
reduce the entire counts of the diurnal pattern to half of the values entered
(see figures below).
Example 1:
road pattern „patt_01“ with
18000 veh./18 h selected,
input of Q=0 considers the
pattern as entered
NOTE - Receiver levels may
differ compared with input of
Q=18000 since low traffic
correction is applied with Q=0
by default (see chapter 6.2.10.6
"CRTN")
Example 2:
road pattern „patt_01“ with
18000 veh./18 h selected,
input of Q=9000 considers half
the amount of the pattern
selected (i.e. 9000 veh./18 h)
With the option "Use Non Standard Reference Time D/E/N" activated see
chapter 6.2.10.6 "CRTN".
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Chapter 2 - Sound Sources
2.4.7 CRTN
According to CRTN, paragraph 4, the source of traffic noise (emitting line
source) has to be taken 0.5 m above the road surface level and 3.5 m inwards
from the nearside of the road’s edge (curb). This definition, however, refers
to a situation with just receivers on one side of the road. In CadnaA, source
lines are generated on either side of the road as the procedure should be applicable also to more complex scenarios with receivers on either side of the
road or with grid calculations.
CRTN-road with
two emission lines
(curb-to-curb distance 8 meters),
radiation occurs
just from the
source line being
closer to the
receiver
(option „Generate
Rays“ activated on
dialog Receiver)
close-up:
ray is extending
from the near
source line,
source position is
3.5 meters inwards
from the road’s
curb
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Road & Source
Geometry
2
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Chapter 2 - Sound Sources
2.4.7 CRTN
The distance from the source line to the curb has no influence on the
emission of the road, i.e. just enabling to identify the location of the road's
curb in relation to the source position. The default distance of 3.5 m is
specified on the Options menu, Appearance (see chapter 2.4.1 "Common
Input Data", section "Specification of Road Width").
2
With receivers on either sides of the road both emission lines radiate.
Radiation by a CRTN-road with two receivers on either side
(curb-to-curb distance 8 meters)
Additional Width
With the self screening-option activated (see chapter 2.4.1, section "Dialog
Geometry"), the actual road width can be specified by entering an additional
width > 0 m for either side of a road. The additional width overrides the additional width defined on dialog Options|Appearance. In this case the
source position referring to the road‘s center line is still the same, but the
curb distance deviates from the default value of 3.5 m and, thus, the total
road width.
In conjunction with the option „Roads/Parking Lots are reflecting (G==0)“
activated (see chapter 6.2.7) this affects the resulting levels.

As self-screening is not treated in CRTN at all, one could conclude to
not apply the self-screening option when using CRTN in CadnaA.
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2.4.7 CRTN
Example: For a road of a total width of 12 m curb-to-curb (input for „SCS/
Dist. (m)“ is „w12“) and with the additional widths 5 m left and 10 m right
the new road width calculates from:
 Examples\
02_Sources\ Road\
CRTN road width using
add. width.cna
source line distance: 12 - (2 x 3.5) = 5 m
source from curb, left side: 5+1.75 = 6.75 m
source from curb, right side: 10+1.75 = 11.75 m
total width curb-to-curb: 5 + 6.75 + 11.75 = 23.5 m
The following speed correction applies:
Speed Correction
500 

 5p 
 pV  33 lgV  40 
  10 lg1 
  68.8 dB( A)
V 
V 


where
V is the road type specific traffic speed (see table 6.1 in CRTN /81/, in km/h
p is the percentage of heavy vehicles, calculated according to: p 
100 f 100 F

q
Q
f is the hourly flow of heavy vehicles
F is the 18-hour flow of heavy vehicles

Despite the limitation of chart 4 in CTRN, CadnaA applies this speed
correction for any speed, also below 20 km/h and above 130 km/h.
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Road Surface
2
Chapter 2 - Sound Sources
2.4.7 CRTN
The following road surface types are available from the list box on dialog
Road:
Attribute
Value
STRONR
road surface correction TD in dB
at a speed of (with TD: texture depth in mm)
Road Surface
<= 75
km/h
> 75 km/h
0
(manual input of attribute DSTRO)
1
(no correction)
0
2
Impervious, concrete
-1
TD  10 lg90  TD  30  20 dB( A)
3
Impervious, bituminous
-1
TD  10 lg20  TD  60  20 dB( A)
4
Pervious
0
- 3.5
-3.5
Default texture depth: 5.0 mm (attribute TEXDEP)
Gradient (%)
The road gradient can be edited manually by selecting "Input (%)" or be calculated automatically from the height points of the road polygon. This feature enables for a single road to calculate the gradient correction for each
road section separately (for more details see chapter 2.4.1 "Common Input
Data", section "Road Gradient (%)"). CadnaA applies the correction according to CRTN chart 6 for positive and negative gradients G:
 G  0.3 G dB ( A)

with G gradient in %
Furthermore, the traffic speed V on roads with gradients has to be
reduced by V in accordance with CRTN, chart 5. This speed reduction
is not accounted for by CadnaA automatically. Instead, always the
entered speed is used for the speed correction.
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2.4.8 TNM
2.4.8
TNM
Note - The Federal Highway Administration Traffic Noise Model (FHWA TNMTM) is
protected by U.S. copyright laws. The noise prediction methodology used in CadnaA has
been designed to be consistent with the FHWA TNMTM, however, CadnaA has not been
tested, evaluated, or approved for use by any Agency of the U.S. Government.
The emission parameter in TNM („Traffic Noise Model“) is the A-weighted
level Ltraf,ref in dB(A) at a distance of 50 ft. (15.24 m) perpendicular to the axis
of a road with infinite length with absorbing flat ground /89/.
2
Emission Parameter
In TNM, emission is based on A-weighted levels (expressed in energy form),
while sound level computations use one-third octave-band data, converted to
A-weighted levels for display and output.
Dialog Road (for TNM)
The vehicle categories and their definitions available in TNM are listed in the
subsequent table.

For the time being, CadnaA does not allow for user-defined vehicle
categories.
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2
Emission Scheme
Chapter 2 - Sound Sources
2.4.8 TNM
TNM-vehicle categories
Definition
autos
all passenger cars (2 axles, 4 tires), gross mass < 4500 kg (<
9900 lb)
medium trucks
cargo vehicles (2 axles, 6 tires), 4500 kg < gross mass
< 12000 kg (9900 lb < m < 26400 lb)
heavy trucks
all cargo vehicles with 3 and more axles, gross mass
> 12000 kg (> 26400 lb)
buses
all vehicles (2 or 3 axles) designated for transportation of 9
or more passengers
motorcycles
all vehicles with 2 or 3 tires with an open-air driver and/or
passenger compartment
The emission for each category, pavement type and throttle setting, is
represented by 17 constants (2*7+3=17, resulting in 17*(5*4*2)= 680
constants in total) applying the following equations.
The radiated energy EA is:
E A ( si )  (0.6214  si ) A / 10  10 B / 10  10C / 10 ,
converted to A-weighted levels per third-octave band:
7
Lemis ,i ( si , f )  10 lg E A    X 1  0.6214  X 2  si   lg f
j 1
j 1
with
 X 1; X 2   D1; D2 , E1; E2 ,..., J1; J 2 
where
si
A1...J1, A2...J2
f
speed of vehicle type i (in km/h)
constants (see table 5 in /90/)
frequency (in Hz)
Converted back to its energy form:
Eemis (si , f )  10
Lemis ,i / 10
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2.4.8 TNM
The emission level Ltraf,ref is not displayed in the TNM 2.5 software. Instead,
the emitted energy E for each vehicle category can be exported to a csv-file
using the procedure described in the box below.
2
Exporting spectra of energy parameter E from TNM 2.5 software:
1 - locate the file tnm.ini in C:\WINDOWS
2 - open the file and add the section:
...
[Diagnostics]
emission=1
...
3 - with each TNM-calc run a file emit.csv is written besides the *.dat and *.idx files
4 - emit.csv lists the energy parameter E for each category and sub-source type
5 - sum E for all categories and sub-source types gives after conversion Ltraf,ref
Specification of
Emission
CadnaA offers to introduce traffic data based on Mean Daily Traffic Data
(MDTD), though not available in the original TNM. In this case, the number
of vehicles per hour and the percentage trucks/buses is calculated according
to the specifications in the Austrian road noise standards RVS 3.02 /59/ and
RVS 4.02 /60/.

For details (and tables) on the traffic count (veh/h) and proportion of
heavy vehicles (%) for each type of road see chapter 2.4.3 "Nordic Prediction Method 1996", section "MDTD".
In this case, the percentages of motorcycles and of heavy trucks and buses
are, however, 0% for all road types as those vehicles types are not considered
in the Austrian road noise standards RVS 3.02 and 4.02.
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Exact Counts
2
Chapter 2 - Sound Sources
2.4.8 TNM
This option enables to enter counts for the five TNM-specific vehicle types,
comprising autos (cars), medium trucks, heavy trucks, buses, and
motorcycles. As traffic data in TNM is specified in absolute figures for each
vehicle type, while CadnaA uses - as the majority of road noise standards do
- a scheme based on hourly overall traffic and percentage, the following transformations apply to convert absolute figures:
Input data
CadnaA
Attributes
calculates from TNM-input data according to ...
number of
vehicles/hour
MT, ME,
MN
n Autos  nMedium Trucks  nHeavy Trucks  nBuses  nMotorcycles  ntot
Percentage of
Trucks/Buses
(%)
PT, PE,
PN
n
Percentage of
Motorcycles
(%)
PLAT,
PLAE,
PLAN
Percentage of
heavy vehicles:
Heavy Trucks
(%)
PLT, PLE,
PLN
nHeavy Trucks / nMedium Trucks  nHeavy Trucks  nBuses * 100%
- Percentage of
heavy vehicles:
Buses (%)
PLLAT,
PLLAE,
PLLAN
nBuses / nMedium Trucks  nHeavy Trucks  nBuses * 100%

Medium Trucks
 nHeavy Trucks  nBuses / ntot * 100%
nMotorcycles / ntot * 100%
A scheme using hourly traffic and percentages has the advantage that
overall traffic figures can be changed without altering the traffic mix.
 File
Examples\02_Sources\Road\Road\Calc CadnaA-figures from TNM-figures.xls
Ltraf,ref dB(A)
direct input of Ltraf,ref in dB(A)
Diurnal Pattern
see chapter 2.4.1 "Common Input Data", section "Diurnal Pattern"
Source Geometry
Depending on vehicles type, sub-sources are located at different heights (at
0.1 m for tire, 1.5 m (5 feet) for engine, and 3.66 m (12 feet) for stack, all
above ground).
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2.4.8 TNM

A height of 0.1 m for the tire source as in TNM 2.5 software is used,
while the TNM 1.0 documentation states a height of 0.0 m instead.
Traffic speed can be specified for "Autos" and - if activated - for "Trucks"
separately (in km/h). The speed limit entered for "Autos" will be considered
as limit for autos and motorcycles, while the speed limit entered for "Trucks"
- if any - will be considered for medium and heavy trucks, and for buses. With
the limit entered just for "Autos" (i.e. "Trucks" deactivated) the value applies
to all types of vehicles (no intrinsic speed limit for trucks).

Speed Correction
Accelerating ramps and flow control devices are not available in
CadnaA for the time being.
see chapter 2.4.1, section "Button DEN"
Button DEN
The following TNM-specific road surface types are available:
Road Surface
Attribute Value
STRONR
Road Surface Type
1
Average
i.e. average of DGAC and PCC
2
DGAC
dense-graded asphaltic concrete
3
OGAC
open-graded asphaltic concrete
4
PCC

Explanation
Portland cement concrete
FHWA states that the „average pavement type shall be used in the
FHWA TNM for future noise level prediction unless a highway agency
substantiates the use of a different pavement type for approval by the
FHWA.“
The road gradient is not considered by CadnaA when calculating TNMspecific emission for the time being.
Road Gradient (%)
TNM has two kinds of operating conditions causing a different emission:
„cruise throttle“ and „full throttle“. With the option „Throttle“ activated the
respective road will be considered as a full throttle road.
Throttle
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Chapter 2 - Sound Sources
2.4.8 TNM
2
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Chapter 2 - Sound Sources
2.4.9 Czech Method
2.4.9
Czech Method
The emission parameter according to the Czech Method is the A-weighted
equivalent continuous sound pressure level LAeq,7.5m at a reference distance of
7.5 m from the center line of the outer lane of an infinite straight road with
free sound propagation /95/.
Emission Parameter
The mean level LAeq,7.5m calculates from:
Emission Level
LAeq,7.5m
LAeq , 7.5 m  10 lg X  10.1 in dB(A)
with the correction X:
X  F1  F2  F3
where
•
•
•
the factor F1 expresses the influence of the speed of the traffic flow and
the percentage of the lorries,
the factor F2 expresses the influence of the road gradient (slope), and
the factor F3 expresses the influence of the road pavement.
Dialog Road (for Czech Method)
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Chapter 2 - Sound Sources
2.4.9 Czech Method
The factor F1 is calculated separately for daytime (6-22 h) and nighttime (622 h) according to:
2
F1  nOA  FvOA  10 LOA / 10  nNA  FvNA  10 L NA / 10
where
nOA
average traffic flow per hour of the cars (Day or Night)
average traffic flow per hour of the lorries and buses (Day or Night)
nNA
FvOA speed dependence of the equivalent sound pressure level on the traffic flow
consisting from the cars only (see below)
LOA
A-weighted sound pressure level of the passenger cars for the year under
consideration, given in the table in section „Particular Years“ (see below)
FvNA speed dependence of the equivalent sound pressure level on the traffic flow
consisting from the lorries and buses only (see below)
LNA
A-weighted sound pressure level of the lorries and buses for the year under
consideration, given in the table in section „Particular Years“ (see below)
FvOA is given by: F  3.59  10 5  v 0.8 for v <= 60 km/h
vOA
FvOA  2.70  10 7  v 2
for v > 60 km/h
2
0.5
FvNA is given by: FvNA  1.50  10  v
for v <= 60 km/h
FvNA  2.45  10 4  v 0.5 for v > 60 km/h
Particular Years
Particular sound pressure level LOA (in dB) for cars, and LNA (in dB) for
trucks and buses for years 1995-2005 are given in the next table.
Year
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
level LOA
cars, dB(A)
77.9
77.4
76.8
76.2
75.6
74.9
74.8
74.6
74.4
74.3
74.1
level LNA
trucks and buses, dB(A)
85.4
84.7
84.0
83.3
82.4
81.4
81.1
80.9
80.7
80.4
80.2
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2.4.9 Czech Method
Specification of
Emission
Specifying the „Mean Daily Traffic Density“ (MDTD, veh/24h) calculates
the emission level LAeq,7.5m depending on the road type based on the hourly
traffic data M (veh/h) and the truck proportion p (%) according to the table
below.
Attribute Value
STRGATTNR
Road Type
daytime
(6-22 h)
MDTD
nighttime
(22-6 h)
M *1)
(veh/h)
p *2)
(%)
M *1)
(veh/h)
p *2)
(%)
0
Motorway
0.0563 DTV
(=0.9/16)
25
0.0125 DTV
(=0.1/8)
12.5
1
Landscape
mixed
0.0581 DTV
(=0.93/16)
20
0.0087 DTV
(=0.7/8)
10
2
Settlement
mixed
0.06 DTV
(=0.96/16)
20
0.005 DTV
(=0.04/8)
10
3
Recreational
0.0606 DTV
(=0.97/16)
10
0.0038 DTV
(=0.03/8)
3
*1) M = nOA + nNA
*2) p = nOA/(nOA + nNA) * 100%
Any number of vehicles per hour M and other proportions of trucks p% can
be specified when selecting this option.
Exact Count Data
for direct input of the emission level
LAeq,7.5m
see chapter 2.4.1 "Common Input Data", section "Diurnal Pattern"
Diurnal Patterns
The speed correction in CadnaA is based on the speed entered (whether it
complies with an actual speed limit or not).
Speed Limit (km/h)
The height entered in the dialog Geometry is the height of the road’s surface.
The source height is 0.5 m above the road’s center line or above the center
lines of the outer lanes.
Source Geometry
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Road Gradient (%)
Chapter 2 - Sound Sources
2.4.9 Czech Method
The factor F2 expresses the influence of the slope s on the level LAeq,7.5m (see
subsequent table).
2
One-way road
Two-ways road
Inclining
Road Surface
Declining
%
F2
%
F2
%
F2
1.00
s<1
1.00
s <= 6
1.0
s<1
1 <= s < 2
1.12
s>6
2.5
1 <= s < 2
1.06
2 <= s < 3
1.25
2 <= s < 3
1.13
3 <= s < 4
1.42
3 <= s < 4
1.21
4 <= s < 5
1.60
4 <= s < 5
1.30
5 <= s < 6
1.79
5 <= s < 6
1.40
s=6
2.00
s=6
1.50
s>6
2.50
s>6
2.50
The factor F3 expresses the influence of the road pavement on the level
LAeq,7.5m. The correction for different road surfaces DStrO (in dB) can be
entered or selected from the list box (for speeds > 50 km/h). By default, the
road surfaces listed in a following table are available.
For speeds < 50 km/h, the factor F3=1.0 for all types of asphalt concrete and
concrete pavements. For the same speed range the factor is F3=2.0 for the
small set pavings and F3 = 4.0 for the set pavings.
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Chapter 2 - Sound Sources
2.4.9 Czech Method
Attribute
Value
STRONR
Pavement
Category
1
Aa
Asphalt concrete - AC-8
Asphalt concrete continuously graded
1.0
2
Ab
Gap-graded asphalt concrete for very thin
layers ACVTL-11 (e.g. type RUMAC)
1.0
3
Ac
Stone mastic asphalt SMA-11 or another asphalt
with grading up to 11 mm (e.g. type ULM)
1.1
4
Ad
Asphalt concrete AC-16HE with the use of
modified bitumen
1.1
5
Ae
Cold micro surfacing with grading up to 8 mm
(e.g. type GRIPFIBRE)
1.2
6
Ba
Concrete pavement with texture with towed jute
1.2
7
Bb
Concrete pavement with negative transverse
roughness
1.2
8
Bc
Concrete pavement with fine transverse roughness
1.5
9
Ca
Small set paving (surface course)
2.0
10
Cb
Set paving (surface course)
4.0
Road Surface
Factor F3
Multiple reflections within an urban road can be corrected for by the
correction for multiple reflections according to RLS-90. This enables to reduce the order of refections considered by image sources (see chapter 6.2.8
"Reflection Tab").
see chapter 2.4.2 "RLS-90", section "Correction for Multiple Reflections" for
details
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Correction for
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Chapter 2 - Sound Sources
2.4.9 Czech Method
2
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Chapter 2 - Sound Sources
2.4.10 SonRoad
2.4.10
SonRoad
According to the Swiss road noise model „SonRoad“ the A-weighted sound
power level LwA in dB(A) emitted by the two vehicle types autos and trucks
calculates from /94/:
- for autos:


  v  3.5 

0.1 60.5 10 lg  1      S  


  44  
 0.17.3 35 lg v   BR 



LwA , autos  28.5  10 lg10
 10 
   BG




- for trucks:
LwA , trucks
2 157


  v  3.5 

0.1 74.7 10 lg  1      S  


  56  
 0.116.3 35 lg v   BR 




 28.5  10 lg10
 10
   BG




where
v: speed of autos or trucks, in km/h
BR: correction for roll noise component on road surfaces (tabulated, see below), in dB(A)
BG: correction for total noise component on road surfaces (tabulated, see below), in dB(A)
S: gradient correction, in dB(A)
Dialog Road (for SonRoad)
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Chapter 2 - Sound Sources
2.4.10 SonRoad
In SonRoad, the emission is based on A-weighted sound power levels, while
the calculation of propagation occurs in one-third octave-bands, in CadnaA
converted to octave band levels and A-weighted levels.
2
The A-weighted sound power per unit length L’wA in third-octave bands
results from:
 23  N
0.1 L
L 'wA  10 lg   autos 10
 j 0 v
  autos
wA ,a utos Y
 j 

N trucks 0 .1L
10
vtrucks
wA , tr ucks Y
 j   
  30 dB  MK  K1


where
Nautos, Ntrucks: number of autos/trucks per hour
vautos, vtrucks: speed of autos/trucks, in km/h
Y(j): third-octave values of the reference spectrum (see below), in dB(A)
j: running number of third-octave
ML, K1: model & level corrections (see below)
Reference Spectrum
The values X(j) represent the A-weighting spectrum. As the emission data
was measured on hard ground the final spectrum Y(j) results.
j
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Frequency
(Hz)
100
125
160
200
250
315
400
500
630
800
1000
1250
1600
2000
2500
3150
4000
5000
X(j) in
dB(A)
-20
-20
-18
-16
-15
-14
-13
-12
-11
-9
-8
-9
-10
-11
-13
-15
-16
-18
Y(j) in
dB(A)
-24.3
-24.3
-22.3
-20.2
-19.1
-17.9
-16.6
-15.1
-13.4
-10.3
-7.6
-6.6
-7.5
-10.9
-14.5
-15.5
-15.1
-18.7
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2.4.10 SonRoad
Specification of
Emission
CadnaA offers to introduce traffic data based on Mean Daily Traffic Data
(MDTD), though not available in SonRoad originally. In this case, the number of vehicles per hour N and the percentage trucks/buses eta (%) is calculated for the road type „Switzerland“ according to the specifications in the
Swiss road noise standard STL-86 /64/.
Road Type
Switzerland
Day
(6-22 h)
MDTD
Night
(22-6 h)
N
(veh/h)
Eta
(%)
N
(veh/h)
Eta
(%)
0.058 MDTD
10
0.009 MDTD
5
This option enables to enter the five hourly traffic figures N and percentage
of heavy vehicles eta (%) for the time periods D/E/N.
Exact Counts
direct input of L’wA in dB(A)
L’wA dB(A)
see chapter 2.4.1 "Common Input Data", section "Diurnal Pattern"
Diurnal Pattern
The model correction MK can - as already available for STL86 /64/ - be entered for each road and time periods D/E/N individually.
Model Correction MK
The level correction K1 is a low traffic correction according to:
Level Correction K1
 5 : N  31.6


 N 
K1  10 lg
 : 31.6  N  100
 100 


0 : N  100
where N: total number of vehicles per hour
The speed correction in CadnaA is based on the speed entered (whether it
complies with an actual speed limit or not).
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Speed (km/h)
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Chapter 2 - Sound Sources
2.4.10 SonRoad
Source Geometry
The source height in SonRoad is 0.45 m above ground.
Road Surface
The table below lists the road surface corrections for the total noise (BG) and
for the roll noise (BR).
BG
dB(A)
Surface Type
asphalt concrete AC 8,11,16 (also AB 10,11,16)
0
0
concrete (depending on age and condition)
+2
0
porous asphalt PA 8,11 (formerly drain asphalt DRA 10,11) for speeds
v > 70 km/h
-4
0
mastic asphalt MA 8,11,16 (formerly GA)
0
0
rough asphalt AC MR 8,11 (formerly also Macro-Rugeux MR 6,11)
-1
0
surface treatment OB 3/6
0
0
surface treatment OB 6/11
+1
0
stone mastic asphalt SMA 6
-1
0
stone mastic asphalt SMA 8,11
0
0
chipped mastic asphalt SPA 6,8,11
0
0
asphalt concrete TA 10
0
0
asphalt concrete TA 16
+1
0
0
+6
pavement (Note - Larger individual spread is likely.)
Road Gradient (%)
BR
dB(A)
A positive road gradient g (i.e. uphill) results in the level correction:
 S  0.8  g for g > 0%
Roads with negative slope (i.e. downhill) receive no correction.
Correction for
Multiple Reflections
Multiple reflections within an urban road can be corrected for by the
correction for multiple reflections according to RLS-90. This enables to reduce the order of refections considered by image sources (see chapter 6.2.8
"Reflection Tab").
see chapter 2.4.2 "RLS-90", section "Correction for Multiple Reflections" for
details
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Chapter 2 - Sound Sources
2.4.11 HJ 2.4 (2009)
2.4.11
HJ 2.4 (2009)
The emission parameter according to the Chinese standard HJ 2.4 (2009) is
the mean level Le,7.5m at 7.5 m distance from the road’s axis of an infinite
straight road with free sound propagation /93/. For each of three vehicle
types i it holds:
L
2 161
 
  L   10lg  NV    L
e ,7.5m i
i
0E i

i

slope,i
  L road surface  16
where
(Le,7.5mE)i
equivalent sound emission level of i-type vehicle per hour, in dB(A)
energetic average of the A-weighted sound pressure level i for an i-type
(L0E)i
vehicle with speed Vi (km/h) at a horizontal distance of 7.5m, in dB(A)
Ni
average hourly traffic volume of i-type vehicle passing by, for daytime
and nighttime, 1/h;
Vi
average speed of i-type vehicle, km/h
gradient correction for i-type vehicle, dB
Lslope,i
road surface correction, dB
Lroad surface
Dialog Road (for HJ 2.4 - 2009)
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Emission Level L0E
Chapter 2 - Sound Sources
2.4.11 HJ 2.4 (2009)
The emission level depends on vehicle category i:
i
2
vehicle
class
gross
vehicle
mass
corresponding Chinese
vehicle types
(L0E)i
dB(A)
1
small
< 3500 kg
M1, M2, N1
(L0E)i=1 = 12.6 + 34.73 log V1
2
medium
3500 12000 kg
M2, M3, N2
(L0E)i=2 = 8.8 + 40.48 log V2
3
large
> 12000
kg
N3
(L0E)i=3 = 22.0 + 36.32 log V3
The equivalent sound pressure level of the total vehicle flow at 7.5 m distance
from the road‘s axis results from:
3
Le,7.5m  10 lg 10
0.1Le ,7 ,5 m ,i
i 1
MDTD
The „Mean Daily Traffic Density“ (MDTD, vehicles/24h) does not exist in
HJ 2.4 (2009) as an input parameter for traffic data. Nevertheless, this feature
is provided by CadnaA applying the road types of the Austrian road noise
standards RVS 3.02 /59/ and RVS 4.02 /60/.
Regarding the traffic mix assumed depending on the selected road type see
chapter 2.4.3 "Nordic Prediction Method 1996".
Source Geometry
The height entered in the dialog Geometry is the height of the road’s surface.
By default, the source height is at the height of the road’s center line or above
of the center lines of the outer lanes (default value: 0.0 m).
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The valid speed range for vehicle classes i=1..3 is:
i
vehicle class
valid speed range
1
small
63 km/h to 140 km/h
2
medium
53 km/h to 100 km/h
3
large
48 km/h to 90 km/h
Speed Range
2
Outside the mentioned speed range the sound power emitted by the point
source/s resulting from segmentation of the road is constant using the
respective lower or upper limit. Nevertheless, when entering speeds outside
the valid speed range the displayed emission value of the road (here Le,7.5m)
will change since the speed itself alters this value due to longer pass-by
duration (at lower speeds) or shorter pass-by duration (at higher speeds).
The correction for different road surfaces Lroad surface can be entered or
selected from the list box providing the road surface types of HJ 2.4. The
available road surfaces are listed in a following table.
Attribute
Value
STRONR *)
Lroad surface in dB
Road Surface
at a speed of
30
km/h
40
km/h
>= 50
km/h
1
Bitumen concrete
0
0
0
2
Cement concrete
1.0
1.5
2.0
*) By the attribute value STRONR=0 the numerical input of DStrO is selected.
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2
Gradient (%)
2
Correction for
Multiple Reflections
Chapter 2 - Sound Sources
2.4.11 HJ 2.4 (2009)
The road gradient g% can be entered or be calculated automatically,
depending on the z-heights of the road. The list box „Road Gradient“ on the
Road dialog the offers different options (see chapter 2.4.1, section "Road
Gradient (%)").
Large Vehicles:
Lslope  98 
g%
100
Medium Vehicles:
Lslope  73 
g%
100
Small Vehicles:
Lslope  50 
g%
100
The reflection model in HJ 2.4 (2009) makes use of the correction for
multiple reflections as specified in RLS-90 /17/. The correction for multiple
reflections - called „Lreflection“ in HJ 2.4 (2009) - depends on the average
height of the buildings left/right and on the distance among them. According
to RLS-90 a correction for multiple reflections applies only when percentage
of gaps between the buildings is less than 30%.
Consequently, when applying this correction for multiple reflections the user
has to ensure that just the first order of reflection is calculated by reflected
rays.
When the option „Calc exactly one reflection order“ on the „Road“ tab
(Calculation|Configuration menu, see chapter 6.2.10.10) is activated, this
occurs automatically. This holds also when a different order of reflection is
specified on the „Reflection“ tab (see Chapter 6.3.9). A calculation without
any reflections can be performed by deactivating the option „Calc exactly one
reflection order“ and specifying no order of reflection (i.e. zero).
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This is the excess sound level due to multiple reflections. When this option is
activated a correction (in dB) for multiple reflections can be entered.
Drefl
2
Alternatively, the correction is calculated from the average height of the
buildings on each side of the road, and the average distance (in m) between
the buildings on both sides of the road according to:
 between reflecting buildings (percentage of gaps < 30%):
Drefl  4 * hBeb / d Beb  3.2 dB
 between absorbing buildings:
Drefl  2 * hBeb / d Beb  1.6 dB
 between highly absorbing buildings:
Drefl  0 dB
average height of the buildings (attribute HBEB)
Average Height (m)
average distance between the buildings (attribute ABST)
Distance (m)
absorption of the buildings (reflecting, absorbing or highly absorbing).
Absorption

According to RLS-90, the correction for multiple reflections - when
specified - is applied independently from the receiver’s distance. In
CadnaA, the correction for multiple reflections is considered in the
road’s emission level (see calculation protocol).
The command Calc Width of Roads (Extras menu) calculates the average
height, the average distance and the proportion of gaps between buildings
parallel to the roads.
Calc Width of Roads
For details see chapter 2.4.2 "RLS-90", section "Calc Width of Roads".
Since HJ 2.4 (2009) applies the same correction scheme for traffic lights as
RLS-90, the object „Crossing“ may be used in road noise models as well (see
chapter 2.5 "Crossings with Traffic Lights").
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2.4.12 Further Procedures for Road Noise
2.4.12
2 167
Further Procedures for Road Noise
Information on the following standards or guidelines for road noise can be
found in the German version of the CadnaA-reference manual:
•
RVS 4.02, Austria
•
StL-86, Switzerland
•
DIN 18005 (1987), Germany
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2.4.12 Further Procedures for Road Noise
2
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2.4.13 Air Pollution according to MLus-92
2.4.13
Air Pollution according to MLus-92
CadnaA enables to calculate the impact by air pollutants caused by road
traffic according to a national German procedure, called MLuS-92, edition
1996 /48/.
The calculation of air pollution according to MLuS-92 in CadnaA assesses as with the simplified noise calculation in RLS-90 - a „Long Straight Road“
scenario. The calculation scheme opens by selecting the command Air
Pollution from the road’s context menu. On the dialog, the relevant input
parameters of this road are transferred from the Road dialog.
Alternatively, open the dialog from the Extras|Air Pollution menu. In this
case, the corresponding parameters such as traffic counts, truck percentage
etc. must be entered manually.

2 169
For the time this dialog has not been translated to English.
The unofficial translation of the terms used on the dialog is listed on the
following page.
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2.4.13 Air Pollution according to MLus-92
German Term
English Term
DTV (Kfz /24 h)
MDTD (cars/24 h)
Lkw-Anteil (%)
HGV%
Pkw-Geschw (km/h)
car speed
Lkw-Geschw (km/h)
truck speed
Windgeschw (m/s)
wind velocity
Wind < 3 m /s (%)
amount of wind situations in % with wind
speed < 3 m/s
Abstand Fb-Rand (m)
distance from road curb
Jahr (1985-2010)
year of evaluation (range 1985-2010)
Einheit/m³
unit/m³ for each component
Vorbelastungstyp
type of preload situation (open land, small/
medium/large town with small/medium/
high load)
Prüfwert
legal requirements (for Germany only),
set to "user defined"
Vorbelastung
preload
Zusatzbelastung
additional load
Gesamtbelastung
total load
Prüfwert
limiting value
Mittelwert
mean value
98-Perzentil
98% statistical value
As an alternative, the dialog can be opened via menu Extras|Air Pollution
(MLUS). In this case, the relevant road parameters have to be entered via the
keyboard.
Values in red indicate an infringement or an incorrect entry.
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2.5 Crossings with Traffic Lights
2.5
2 171
Crossings with Traffic Lights
The majority of standards for road noise do not offer to model road
crossings controlled by traffic lights. The only standards or procedures
defining a correction are RLS-90 /17/, the Swiss „Guideline for Road Noise“
/67/ and CNOSSOS-EU /16/.
The correction for road crossings controlled by traffic lights according to
RLS-90 is applied for all road noise guidelines and standards implemented in
CadnaA, besides
•
•
•
STL86+ /63//64/,
SonRoad /70/ and
CNOSSOS-EU /16/,
provided that the object „Crossing w/ Traffic Light“ is used at all in the
model.
In RLS-90, the location of the object „Crossing“ in the model does not
comply with its physical location, but is the imaginary intersection point of
the respective emission lines (which is a hatched line, by default). This means
that the traffic light‘s location according to RLS-90 does not correspond with
the physical location of the traffic light, but represents the imaginary
intersection of the corresponding emission lines (shown as a dashed line/s by
default).
In the model, the object „Crossing“ is located at the imaginary
intersection point/s of the respective emission lines
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Calculation according
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2.5 Crossings with Traffic Lights
Options
.
Light is active
When allocating a traffic light to a crossing or junction, the penalty according
to RLS-90, section 4.2, table 2, is added to the receiver level automatically
taking into account at what time, day, evening or night, the traffic light is active.
2
distance d of the receiver from the closest
intersection of emission lines
correction K
(dB)
<= 40 m
3
40 < d <= 70 m
2
70 < d <= 100 m
1
> 100 m
0
The correction K is applied only once (at multiple crossings with traffic
lights).
The check boxes enable to specify traffic light’s activity separately for
daytime, evening and night-time. In the graphics, an active traffic light is
indicated by a cross within the square.
Crossing is Roundabout
This option just applies to CNOSSOS-EU, see below.
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2.5 Crossings with Traffic Lights
Any road lying within at a distance < 20 m to the traffic light’s position will
be allocated to this crossing in the calculation, and will be listed on the list
box „Associated Roads“. The option „Find Automatically“ is activated by
default.
Associated Roads,
find automatically
2
To allocate a road to a crossing with traffic lights, enter at least a single active
receiver and start the calculation by clicking the pocket calculator icon.

In RLS-90 it is not explicitly specified how many and which roads in the
vicinity of a traffic light receive the correction K. The procedure applied
in CadnaA prevents from including other roads in the vicinity (e.g. a
highway nearby). The automatic assignment is, therefore, a compromise
not to apply the correction to too many roads.
When selecting this option the respective roads can be assigned manually. Select via the button „Insert“ die name of the roads to be assigned from the table Road.

Roads outside the search radius of 20 m require always have to be
assigned manually in order to receive the correction. When roads
nearby a traffic light are broken into pieces (e.g. with different speed
limits) a manual assignment of all sections in the distance range 20 to
100 m is required.
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Chapter 2 - Sound Sources
2.5 Crossings with Traffic Lights
Example
2
Road crossing with traffic lights: Grid showing the correction
with limiting distances according to RLS-90
Calculation according
to
Swiss „Guideline for
Road Noise“
The correction according to Swiss „Guideline for Road Noise, advice paper
No. 0637“ /67/ is considered only if the road noise standards STL86+ or
SonRoad are selected and the object „Crossing“ is used.
distance d of the receiver from the closest
intersection of emission lines
correction
(dB)
< 25 m
2
25 <= d < 50 m
1
d >= 50 m
0
Furthermore, all remarks as given for RLS-90 hold, especially, with the option „Find Automatically“ being activated (default setting) the distance condition < 20 m to the traffic light’s position is used to decide whether a road is
being listed in „Associated Roads“ or not.
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2.5 Crossings with Traffic Lights
Again, the option „Crossing is Roundabout“ does not apply, see CNOSSOSEU below.
Example
Road crossing with traffic lights: Grid showing the correction
with limiting distances according to the Swiss „Guideline for Road Noise“
In CNOSSOS-EU, the effect of the acceleration and deceleration of vehicles
before and after crossings with traffic lights and at roundabouts is considered
by correcting coefficients CR,m,k and CP,m,k depending on vehicle category
and for crossings and roundabouts separately (for values see CNOSSOS-EU
/16/). Both coefficients are not frequency dependent and are attributed to all
octave bands equally.
The correction terms for rolling noise, LWR,acc,m,k, and for propulsion noise,
LWP,acc,m,k, are linear functions of the distance x (in m) of the point sources resulting from the segmentation of the road/s - to the nearest intersection of
the respective source line with another source line:
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2.5 Crossings with Traffic Lights


x
L WR,acc,m,k  CR ,m,k  max  1 
;0  dB
 100 
2

x

L WP,acc,m,k  CP, m, k  max 1 
;0  dB
 100 
The coefficients CR,m,k and CP,m,k depend on the kind of junction k (k = 1 for
a crossing with traffic lights; k = 2 for a roundabout) and are given for each
vehicle category. The correction includes the effect of change in speed when
approaching or moving away from a crossing or a roundabout.
Note that the correction becomes 0 dB at distances of 100 m and larger:
x  100 m : L WR,acc, m,k   LWP,acc, m,k  0 dB .
Crossing is Roundabout
Activate this option to mark a roundabout. In this case the corrections for
k=2 are applied.

In opposite to RLS-90 and SN 640 578, CNOSSOS-EU considers the
correction for crossings with traffic lights and roundabouts on the
source-side. This, however, may lead to different results depending on
the raster factor applied (see chapter 6.2.3 "Partition Tab").
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2.5 Crossings with Traffic Lights
Example
2
Road crossing with a single traffic light according to CNOSSOS-EU:
All rays extending from a source location at a maximum distance of 100 m from
the traffic light receive a correction (red rays) while rays extending from more
than 100 m distance do not receive the correction (gray rays).
Note that the correction does NOT depend whether the receiver or grid point is
situated closer than 100 m distance from the traffic light‘s location or not.
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2.5 Crossings with Traffic Lights
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2.6 Railways
2.6
2 179
Railways
The sound source „Railway“ is radiating to all sides unless the option „SelfScreening“ is not activated (see chapter 2.4.1 "Common Input Data", section
"Self-Screening").
The railway object may have different heights at each polygon point (see
chapter 4.2). The source is located at the top edge of the rail (railhead) with a
relative height of 0.6 m by default.
Radiation from sound source „Railway“,
relative height 0.6 m
Radiation from sound source „Railway“,
relative height 10.6 m,
option „Self-Screening“ deactivated
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Radiation from sound source „Railway“,
relative height 10.6 m,
option „Self-Screening“ activated,
additional width L/R 2 m each
2
180
2
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Chapter 2 - Sound Sources
2.6 Railways
The command Parallel Object (see manual „Introduction to CadnaA“) on
the context menu of a railway enables to generate barriers, embankments, or
contour lines at a specified distance or to generate station marks into the direction of the road using the command Generate Station (see manual „Introduction to CadnaA“).
The parameters of a railway are entered in edit mode on the dialog Railway
that opens when double-clicking on the railway’s center line.

The subsequent chapters are specific for each standard or guideline
available in CadnaA. These specifications do not represent a copy of
the standardized procedures, rather the way they are implemented.
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2.6.1 Common Input Data
2.6.1
Common Input Data
The dialog Railway offers two display modes, depending on whether the selected calculation standard uses an A-weighted emission parameter or emission spectra.
Note the subsequent remark regarding the validity of the specification of
emission with standards using different sub-sources (see section "Emission
Parameter").
Dialog Railway with A-weighted emission parameter (Schall 03 - 1990)
Dialog Railway with spectral emission (Schall 03 - 2014)
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2.6.1 Common Input Data
Emission
Emission Parameter
2
When the option „Emission“ is selected, values for the standard-specific
emission parameter can be entered for the daily periods Day/Evening/Night
(D/E/N). Whether all three periods are relevant for the calculation depends
on the selected railway standard and/or on the option „Use Non-Standard
Reference Time D/E/N“ on the „Railway“ tab (see e.g. chapter 6.2.11.1).

Train Classes and Penalties
In case the selected calculation standard makes use of sub-sources at
different source heights (with A-weighted or spectral emission), the
specification of the emission is correct only when using the option
„Train Classes and Penalties“ using the train classes specific to the standard. When toggling the option „Emission“ in this case, however, just a
single source height will be used (see dialog Geometry of the „Railway“
object, usually 0.6 m above the railhead).
With this option activated the number of trains for the guideline-specific
train classes can be selected from a list (so-called „List of Trains“). In this
case, CadnaA calculates the resulting emission level from the input data automatically (see guideline-specific chapters).

In CadnaA, the emission spectrum is linear (unweighted), while the
sum level is A-weighted („Tot-A“).
There are two alternatives to define a list with number of trains:
1.
By editing the local table on the dialog Railway. To this end, select the
option „(local)“ from the list box.
2.
By referencing an existing list with number of trains available from the
Tables menu, Libraries (local)|Number of Trains. To this end,
select the name of the train list from the list box.
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2.6.1 Common Input Data
Number of Trains
Use the context menu commands to insert new lines to the local train list.
Editing a local list
2
Editing the local table is useful only when just a single railway section is concerned. In practice, a railway track has to be split into several sections due to
changing parameters relevant for emission (such as track type or bridge penalty). With a local train list this would mean that with any small change (e.g. in
the numbers of trains) each individual section would have to be reedited. To
avoid this effort a list with number of trains is defined and referenced via the
box „List of Trains“ for all relevant railway sections.
Via the table Numbers of Trains (Tables menu, Libraries (local)) a table
listing the number of trains for all railway classes travelling on a railway track
can be compiled. To achieve this reference is established to the railway classes
available from the local or global library (menus Tables|Libraries (global)|
Railway Classes or Tables|Libraries (local)|Railway Classes). Subsequently, this list with number of trains is referenced on dialog Railway by
selecting its name.
This procedure has - compared with a local train list - the advantage that any
changes in the table with the train numbers have to be edited once only, but
will effect all railway section referencing that list, no matter whether the
changes occurs via the table Railway (on the Tables|Sources menu) or via
the list of trains in the edit dialog on dialog Railway. In either case, the
change will be addressed to all railway sections referencing this list of trains.
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Example
Chapter 2 - Sound Sources
2.6.1 Common Input Data
In the subsequent example, two railway sections are referencing to the local
list with number of trains „1“.
2
Now, on dialog Railway of section 1 the number of trains for the first train
class („ICE“) is changed from 30 to 50 trains.
Upon closing the dialog by OK the change will be also become relevant to
railway section 2 which is referencing this train list as well.
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2
This change will also concern the train list „1“ in the local library.
In case the change would have been made to that train list „1“ via the local library, all railway sections referencing this list would have been concerned by
this change.
The input boxes for each train class within the train list depends on the
selected guideline for railway noise and will be explained in the following
guideline-specific chapters.
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Edit Boxes for Railway
Classes
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Import Number of
Trains
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2.6.1 Common Input Data
Lists with Number of Trains can be imported and exported (File menu,
command Import and. Export).
see chapter 7.2.22 "Import / Export of Numbers of Trains"
and regarding import operations:
chapter 8.2 "Creating & Addressing Lists with „Number of Trains“" in the
manual „Introduction to CadnaA“ (including an example)
Purging Tables with
Number of Trains
When files containing train lists are imported, those train lists will be
appended to the existing train lists. In order to prevent the list from
increasing in length, select the command Purge Tables from the Tables
menu to update this list with number of trains. Subsequently, all train lists not
being referenced by any railway section will be deleted.
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2.6.1 Common Input Data
Dialog Geometry
The height entered in the dialog Geometry corresponds with the rail’s top
edge (railhead). The default value is 0.6 m (relative height).
Source Height
When the option „Self-Screening“ on the dialog Geometry is activated the
railway is just radiating into the upper half sphere. For the lower half sphere a
screening effect occurs for all receivers below the railroad’s surface. This
feature enables to define inclined railway lines, either upwards or downwards,
by allocating the height above (relative) ground or an absolute height to every
point of the railway, and by defining an additional width (e.g. considering
sidewalks etc.). Since the option „Self-Screening“ is available, the use of the
object „Bridge“ became superfluous (see chapter 3.3).
Self-Screening
With the self screening-option activated, the actual width of the railway line
can be specified by entering an additional width > 0 m. The additional width
can be defined separately for either side of a railway line.
Additional Width left/
right
2
The graphical representation of the object „Railway“ (also on 3D Special
View) does not consider the additional width (so, being different from the
object „Road“). The specified additional width will, however, be considered
upon calculation. The same holds in the same way for the additional parapets
left/right.
In addition, parapets (e.g. parallel barriers) for the self-screening road can be
defined, either on one or both sides by entering a height left/right > 0 m.
The parapets are treated as fully absorbing on either sides. This characteristic
cannot be changed. Absorbing or reflecting barriers without or with
cantilever can be defined just by using the object „Barrier“ (see chapter 3.2).
The following requirements and properties are to be respected:
•
In any case, the additional width has to be > 0 m.
•
The parapets defined via option „Self-Screening“ are a characteristic of
the railway and are not displayed in the 2D-graphics and not in the 3DSpecial view (see chapter 9.14) for the time being.
•
Barriers defined via option „Self-Screening“ will just screen the own
source (railway), but not the noise from other kinds of sources.
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Stationing from/to
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2.6.1 Common Input Data
This option enables to restrict the length of the barrier along the railway’s axis
with reference to the stationing. In this case, the barrier is just generated for
the range „from-up to“.
This option is particularly useful when modeling bridges in order to suppress
the diffraction around the edge of the railway sections at bridgeheads.
For the automatic assignment two attributes are available:
•
•
only for Ground
Absorption, no Screening
station start: SSCR_ST_B
station end: SSCR_ST_E
With this option being activated, the additional width entered will not cause
any screening effect, but will just be considered when calculating ground
absorption. This requires, however, that the respective option on the configurations is checked (dialog Calculation|Configuration, tab „Ground Absorption“, option „Roads/Parking Lots are reflecting G=0“, see chapter
6.2.7). With this option activated the speed of calculation may increase considerably due to the omission of barrier calculation.
The self-screening effect of the road’s surface - including parallel barriers, if
any - just refers to the respective road itself. Thus, the parallel barriers (parapets) defined via „Self-Screening“ are not seen by other sources.
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Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
2.6.2
Schall 03 (1990)
2
Dialog Railway (for Schall03-1990)
The emission parameter according to Schall 03 (1990) is the mean level Lm,E
at 25 m distance and at 3.5 m height above the rail’s top edge from the railway
line’s axis with free sound propagation /23/. It calculates from (sum of all
relevant train classes i):


Lm , E  10 lg 100.1*51 DFz  D D  Dl  Dv  D Ae    DFb  DBr  DBü  DRa
 i

where
DFz: correction for the type of train
DD: correction for the type of brakes
Dl: correction for train length
Dv: correction for the speed
DAe: correction for aerodynamics
DFb: correction for track type
DBr: correction for bridges
DBü: correction for level/grade crossings
DRa: correction for curves
The basic value of 51 dB(A) is the mean level at 25 m distance and at 3.5 m height above the rail’s
top edge for a single train per hour with a length of 100 m, a speed of 100 km/h, and for 100%
of the vehicles with disc brakes.
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Emission Level
190
2
Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
Type of Train
Abbreviation
2
ICE
EC
IR
D
E
N
S
SB
SH
SRR
G
GN
U
STR
TR1
TR2
Type of Brakes
Type of Train
DFz (dB)
InterCity Express
EuroCity / InterCity
Interregio
passenger train
local train
commuter train
S-Bahn (multiple unit)
S-Bahn Berlin
S-Bahn Hamburg
S-Bahn Rhein-Ruhr
Freight Train (distant)
Freight Train (local)
underground/subway
tram
Transrapid 07/1
Transrapid 07/2
-3
0
0
0
0
0
0
0
0
0
0
0
2
3
0
-1
DD = 10 lg (5 - 0.04 p)
where p: percentage of vehicles with disc brakes referring to the train length (including
locomotive/s)
Train Length
Dl = 10 lg (0.01 l)
where l: sum of all trains of train class i per hour
Speed
Dv = 20 lg (0.01 v)
where v: speed (track or loco max. speed) in km/h
Aerodynamics
DAe = 0 dB for v <= 250 km/h
DAe = 1 dB for 250 km/h < v <= 300 km/h
see /25/
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Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
Track Correction
Attribute Value
FBNR
1
2
3
4
Type of Track
Lawn formation - Tramway
Ballast - Wooden sleepers
Ballast - Concrete sleepers
Concrete Track - no absorption
DFb (dB)
-2
0
2
5
DBr = 3 dB

Bridges
In Schall 03, no distinction is made for different types of bridges.
DBü = 5 dB

2
Level/Grade Crossings
Schall 03 specifies that no additional track correction shall be used
(DFb=0 dB) when applying the correction for level/grade crossings.
Furthermore, the railway section length receiving this correction shall
be twice the road width.
Curves

Radius of Curves r
DRa (dB)
r < 300 m
300 m <= r < 500 m
r >= 500 m
8
3
0
The correction for curves DRa can be specified in conjunction with the
correction for level/grade crossings DBü.
With high-rise building structures lateral to the railway track a correction for
multiple reflections can be considered based on the their distance and their
mean height. For the calculation procedure of the correction see chapter
2.4.2 "RLS-90", section "Correction for Multiple Reflections".
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Correction for Multiple
Reflections
192
2
Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
According to Schall 03 (1990) the correction for multiple reflections is just
assigned to a receiver point when it is located „in the range“ of parallel buildings. Furthermore, Schall 03 does not contain provisions on how to apply the
correction for curved railway tracks. In CadnaA, therefore, the procedure is
applied to each section of the source’s polygon. It is checked whether the receiver point is located within half of the specified distance hBeb. If this is true,
the correction for multiple reflections is applied, otherwise not.
2
Due to this strategy, it may occur that not all sections of the source are
„seen“ from the receiver’s location (see calculation protocol). In order to reduce the number of sections the command Simplify Geo may be applied
(see chapter 11.9 in the manual „Introduction to CadnaA“).
vmax
When specifying a track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
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Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.

Train Classes and
Penalties
2
In the following, the procedure to edit a local train list (with numbers of
trains) is described. To enter a train list in the local library, see chapter
2.6.1 "Common Input Data", section "Number of Trains".
Local Train List
The train type is selected from the list Train Types on the
Library (global)|Railway Group (also called „Train Classes“). By this
selection all relevant parameters, such as train length and speed or percentage
of disc brakes, are specified.
Train Type
Numbers of trains for Day and Night (for Schall 03). In case the numbers are
given by trains per hour, these values have to be multiplied by 16 to obtain
the figure for Day and by 8 for Night.
Number of Trains Day/
Evening/Night

For calculations according to VBUSch /116/ the Evening period is relevant as well (D/E/N = 12/4/8 h).
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2
2
Chapter 2 - Sound Sources
2.6.2 Schall 03 (1990)
Speed
relevant speed of trains of the respective train class (in km/h)
Train Length
length l of a train of the respective train class (in m)
Type Correction
By the type correction Dfz the effect of different kinds of vehicles is
accounted for /23/ /24/. Alternatively, the train type is selectable from a list
of train types.
Type of Vehicle
Vehicle w/ wheel-absorbers (401)
Vehicle w/ disc brakes (403...)
Vehicle w/ disc brakes (Bx)
Subway
Tram
other
Transrapid 07/1 - Magnetic Levitation Train
Transrapid 07/2 - Magnetic Levitation Train
DFz (dB)
-3
-2
-1
2
3
0
0
-1
Emission Lm,E,i (dB)
The emission level Lm,E,i for a train class resulting from the specified
parameter is displayed here.
Library with Number
of Trains
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
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2.6.3 Schall 03 (2014)
2.6.3
Schall 03 (2014)
NOTE - There is no official English version existing of the Schall03 (2014) calculation
procedure. The following chapter provides an unofficial translation of terms and
specifications. DataKustik refuses, therefore, any responsibility or liability for the final
technical correctness of this translation.
2
Emission
With this option activated, the types of locomotives, carriages, and cars or
even entire trains („Train Composition“) can be specified using train classes,
offering to enter corrections per train class or to select a list „Number of
Trains“ (see chapter 2.6.1, section "Number of Trains"). CadnaA will
automatically calculate the emission level from the entered values.
Option „Train Classes and
Penalties"
Dialog Railway (option „Train Classes and Penalties“ selected)
With this option selected, the linear (unweighted) emission level per octave
band can be entered for the time periods D/E/N. In the box „Tot-A“ the Aweighted total level is displayed.
Note that in this case just a unique source height can be used and that,
consequently, the sub-sources (see section „Source Type m“) cannot be
applied (see dialog Railway|Geometry, standard source height 0.6 m above
ground level = railhead).
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Option „Emission Lw' “
196
2
Emission Level
2
Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
The sound power level per unit length LW'A,f,h,m,Fz,l in octave band f, at the
height h, for the sub-source m, of a single vehicle unit Fz per hour, with the
number sources nQ and at a speed vFz calculates according to /26/:
L W',f ,h,m,Fz ,l  a A ,h,m,Fz  a f ,h,m,Fz  10 lg
with
nQ
v
dB  bf ,h,m lg Fz dB    c1f,h ,m,c c2f ,h,m,c    Kk
nQ ,0
v0
c
k
aA,h,m,Fz: A-weighted total level of the sound power per unit length
at a reference speed of v0=100 km/h on ballasted track with sleepers and
with average surface condition, accord. to supplement 1 and 2, in dB
Daf,h,m,Fz: level difference in octave band f in dB
nQ: number of sources of the actual vehicle unit
nQ,0: reference number of sources of the actual vehicle unit
bf,h,m: speed factor
v0: reference speed (=100 km/h)
(c1f,h,m+c2f,h,m): sum of corrections for type of track and track surface in dB
K: sum of corrections for bridges and prominence of noise types in dB
The sound power level per unit length in octave band f and at height h by nFz
vehicle units per hour calculates from:


L W'A,f ,h  10lg   n Fz100,1 LW ',f ,h ,m, Fz ,l  dB
 m,Fz


The calculation of the noise emission from marshaling yards is available
in CadnaA by selecting the standard „Schall 03 (2014)“ from the list of
industrial standards (see chapter 2.1.11).
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Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
•
Trains (see Table 3 in /26/):
Vehicle Type
High Speed EMU Locomotive
High Speed EMU Car, not powered
High Speed EMU train
High Speed EMU, train tilting
Electric Multiple Train and Electric
Commuter Train, type „S-Bahn“ (ET)
Diesel Multiple Unit (VT)
Locomotive, Electric („E-Lok“)
Locomotive, Diesel („V-Lok“)
Passenger Car
Freight Car

•
Type of Vehicles Fz
Category Fz
Reference
Number of
Axles
nAchs,0
Vehicle Length
(m)
1
2
3
4
5
4
4
32
28
10
20
26
200
185
52
6
7
8
9
10
6
4
4
4
4
68
20
20
26
20
Train compositions according to Table 4 /26/ („Verkehrsdaten für
Eisenbahnen“, „Traffic Data for Trains“) are available from the library
of global train classes (see chapter 2.6.12, section "Application
Schall03 (2014)").
Trams (see Table 12 in /26/):
Vehicle Type
Tram - Low-Floor Vehicle
Tram - High-Floor Vehicle
Subway/Underground Vehicle
CadnaA - Reference Manual
Category Fz
Reference
Number of
Axles
nAchs,0
21
22
23
8
8
8
2
198
2
Sub-Sources m
Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
•
for trains (see Table 3 in /26/):
subsource
m
height hS
above
railhead
Rolling Noise
1
0m
rail roughness
2
0m
wheel roughness
3
4m
emission of the rolling noise due rail roughness,
transmitted by structure-borne sound via the
body of tank wagons
4
4m
emission of the rolling noise due wheel roughness,
transmitted by structure-borne sound via the
body of tank wagons
5
5m
pantograph
6
4m
bottom of pantograph, grids at cooling and air
conditioning devices in roof section
7
0m
airflow around bogies
8
4m
ventilators of cooling and air conditioning devices,
suction opening in roof section
9
0m
ventilators of cooling and air conditioning devices,
suction & pressure openings from underfloor
10
4m
exhaust system
11
0m
engine, gearbox
2
Aerodynamic Noise
Noise by Technical
Devices
Traction Noise
•
Origin of Noise, Component
Source Type
for trams (see Table 12 in /26/):
Source Type
subsource
m
height hS
above
railhead
Rolling & Traction
Noise
1
2
Noise by Technical
Units
Origin of Noise, Component
vehicle
category
Fz
0m
rail roughness
21, 22, 23
0m
wheel roughness, engine, gearbox
3
0m
power converters, compressor,
air conditioning & ventilation
devices
22, 23
4
4m
power converters, compressor,
air conditioning & ventilation
devices
21
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2.6.3 Schall 03 (2014)
•
for trains (reference speed v0=100 km/h, see Table 6 /26/:
Speed Factor b
speed factor b at octave band center frequency (Hz)
•
Source
Type
Sub-Source m
63
125
250
500
1000
2000
4000
8000
rolling
noise
1, 2, 3, 4
-5
-5
-5
0
10
25
25
25
aerodynamic
noise
5, 6, 7
50
noise by
technical
devices
8, 9
-10
traction
noise
10, 11
20
2
for trams (reference speed v0=100 km/h, see Table 14 /26/:
speed factor b at octave band center frequency (Hz)
Source Type
SubSource
m
63
125
250
500
1000
2000
4000
8000
Rolling & Traction Noise by
Low- and HighFloor Vehicles
1, 2
0
0
-5
5
20
15
15
20
Rolling & Traction Noise,
Subway/Underground Vehicles
1, 2
15
10
20
20
30
25
25
20
Noise by
technical devices
3, 4
-10
When specifying a track-relevant maximum speed vmax the speed of trains/
trams will be adjusted if necessary. In the calculation the smaller of both
values is used.
CadnaA - Reference Manual
Maximum Speed vmax
200
2
Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
•
Type of Tracks
2
attribute
value
FBNR
correction c1 for track types of trains (see table 7 /26/):
parameter
level corrections c1 in dB at octave band center frequency (Hz)
63
125
250
500
1000
2000
4000
8000
1
ballasted track on sleepers
0
0
0
0
0
0
0
0
2
slab track, not
absorbing
increased rail
radiation
0
0
0
7
3
0
0
0
reflection
from surface
1
1
1
1
1
1
1
1
increased rail
radiation
0
0
0
7
3
0
0
0
reflection
from surface
0
0
0
-2
-2
-3
0
0
increased rail
roughness
0
0
0
8
4
0
0
0
3
4
slab track with
absorber
railroad crossing
*)
reflection
1
1
1
1
1
1
1
1
from surface
*) The level correction for railway crossings is on cuts, corresponding to the 2-fold width of the road, to be set.
Level correction for other types of roads are not taken into consideration.
•
correction c2 for track types of trains: The emission spectra of each train
class applies to a track with sleepers (made of concrete, wood or steel)
with ballast and with an average surface condition of the rail‘s surface
without any specific acoustic measures at the rail. For the rail‘s surface
condition „Special Surveillance (SpecSur)" (called „BüG“ in /26/) and
for measures at the rails themselves the following corrections c2 apply
(see table 8 /26/):
track type
subsrce
m
level corrections c2 in dB at octave band center frequency (Hz)
63
125
250
500
1000
2000
4000
8000
track with special surveillance
(SpecSur)
1, 3
0
0
0
-4
-5-
-5
-4
0
rail dampers
1, 3
0
0
0
-2
-3
-3
0
0
2, 4
0
0
0
-1
-3
-2
0
0
1
0
0
0
-3
-4
-5
0
0
rail dampers + special surveillance
(SpecSur)
1, 3
0
0
0
-6
-8
-8
-4
0
2, 4
0
0
0
-5
-8
-7
-4
0
rail screening + special surveillance
(SpecSur)
1
0
0
0
-7
-9
-10
-4
0
rail screening
NOTE - Further provisions apply resulting from the footnotes of the tables for c1 and c2 /26/.
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Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
•
correction c1 for track types of trams (see table 15 /26/):
attribute
value
FBNR
track type
subsrce
m
level corrections c in dB at octave band center frequency (Hz)
63
125
250
500
1000
2000
4000
8000
1
ballasted track on
sleepers
1, 2
0
0
0
0
0
0
0
0
2
track bed on road
surface level and
slab track
1, 2
2
3
2
5
8
4
2
1
3
low level track bed,
covered by lawn
1, 2
-2
-4
-3
-1
-1
-1
-1
-3
-4
-7
-7
-5
4
high level track
1, 2
1
-1
-3
-4
bed, covered by
lawn
NOTE - Further provisions apply resulting from the footnotes of the table /26/.
Level Differences K
CadnaA applies the correction for noise reduction measures NRM (called
„KLM“ in /26/) within the bridge correction (see table 9 & 16 in /26/):
attribute value
DBRI
0
1
2
3
4
5
6
7
8
9
10
bridge type or superstructure type
(no bridge)
direct, steel superstructure
direct, steel superstructure + NRM
ballast, steel superstructure
ballast, steel superstructure + NRM
ballast, heavy plate
ballast, heavy plate + NRM
ballast, steel, noise reduced
ballast, steel, noise reduced + NRM
slab track
grooved rail (tram)
KBr + KLM (dB)
0
12
6
6
3
3
0
3
0
4
4
Schall03 (2014) specifies (see chapters 4.6 and 5.5 /26/) that this correction
at trains and trams is a „combined correction for bridge and track type“ and
that, in this case, no further correction for the track type shall be used. In
CadnaA, therefore, changing the type of track does not cause any effect
provided the option „(no bridge)“ is not selected. In this case, always
„sleepers on ballasted track“ (default case) is assumed.
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Bridges
2
202
2
Curved Tracks
Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
•
2
for trains (see table 11 /26/):
Radius of Curvature r (m)
KL + KLA (dB)
< 300
300-500
>= 500
< 300 Kla
300-500 Kla
8
3
0
5
0
The level correction KLA („long-lasting provisions against squeaking“) is
added.
•
Declining Sections
for trams (see section 5.3.2 /26/):
Radius of Curvature r (m)
K (dB)
< 200
>= 200
4
0
At declining sections with gradients >=2% and a minimum length of 500 m a
penalty of 3 dB on the rolling noise at the height hs=0 m for freight trains
with cast iron block brakes has to be considered due to braking noise.
This specification in Schall03 (2014) requires that, if necessary, a separate
railway object for freight trains with cast iron block brakes has to be entered
in CadnaA to prevent from applying this correction also to other types of
trains running on this section.
Railway Correction
If the so-called „Railway Correction“ (level difference Ks=-5 dB) has to be
applied in order to account for the lower disturbing effect of railway noise,
this has to be entered on the „Railway“ tab (see chapter 6.2.11.2).
Marshaling Yards
In order to evaluate of the noise emitted by marshaling yards the respective
calculation model for industrial sources has to be selected in CadnaA (see
chapter 2.1.11).
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Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
In the following, the procedure to edit a local train list (with numbers of
trains) is described. To enter a train list in the local library, see chapter 2.6.1
"Common Input Data", section "Number of Trains".
Local Train List
The train type is selected from the Library (global)|Railway Group via
the list „Train Types“.
Train Type
Numbers of trains for Day and Night (for Schall03-2014). In case the
numbers are given in trains per hour, these values have to be multiplied by 16
to obtain the figure for Day and by 6 for Night.
Number of Trains Day/
Evening/Night
relevant speed of the trains in a train class (in km/h)
Speed v (km/h)
Enter if necessary the number of axes night one. By default, the reference
number of the respective axes of vehicle used.
Number of Axles
Here the sound power level per unit length LW',i in dB(A) resulting from the
entered parameters for this train class is displayed.
Emission LW', i (dB)
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2
Chapter 2 - Sound Sources
2.6.3 Schall 03 (2014)
2
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Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
2.6.4
Nordic Prediction Method 1996
Two types of evaluation parameters are calculated according to Nordic Prediction Method (NPM) for railway noise (TemaNord 1996:524 /72/):
•
the A-weighted equivalent continuous sound pressure level LA,eq and
•
the A-weighted maximum sound pressure levels LmaxM (energy average
over train length) or LmaxF (highest level with „Fast“ meter setting).
Evaluation
Parameters
As the equivalent continuous level LA,eq is calculated per day (24 h) no specific day- or nighttime values exist. In contrary, a separate procedure is applied
to calculate the maximum level LAFmax.
Dialog Railway (for Nordic Prediction Method)
The emission parameter for evaluations based on Leq is the linear
(unweighted) sound power level per unit length L’wo /72/:
 v 
L'wo  a  lg
  10 lgl24 h   b  Lc
 100 
where
dB re 10-12 W
a,b: constants depending on train type and frequency
v: train speed, in km/h
l24h: total passing train length within 24 hours, in m
Lc: track correction, in dB
CadnaA - Reference Manual
Emission Level L’wo
2
206
2
Emission Level L’wt
2
Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
The emission parameter for maximum level evaluations is the linear
(unweighted) sound power level per unit length L’wt /72/:
 v 
L'wt  a  lg
  10 lg v  43.8  b  Lc
 100 
where
dB re 10-12 W
a,b: constants depending on train type and frequency
v: train speed, in km/h
Lc: track correction, in dB
Two types of levels are used to describe the maximum level of a train passage:
the level LmaxM based on the energy average over train length, and the level
LmaxF the highest level occurring at a passage with „Fast“ meter setting. For
all frequency bands it holds:
 3d 
Lmax F  Lmax M  3   c 
 100 
dB, for electric trains
 3d 
Lmax F  Lmax M  6   c 
 100 
dB, for diesel trains
with dc distance receiver - train centre (m) and the further conditions:
dc > 100 m (electric trains): Lmax F  Lmax M
dc > 200 m (diesel trains): Lmax F  Lmax M

In CadnaA, both types of evaluation levels are available, see chapter
6.2.11.3 "Nordic Prediction Method (1996)"
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Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
In case the option „Train Classes and Penalties“ is selected the track
condition can be entered manually. The track correction Lc is also used to
correct the emission level for joints, crossings, and bridges.
Type of Track
2
Lc
(dB)
ballasted tracks with continuously welded rails on
concrete or wooden sleepers
rails with joints
10 m track length for each unit of switches and crossings
partial track length on a bridge without ballast
partial track length on a bridge with ballast

Track Condition
0
3
6
6
3
CadnaA provides no list box for track conditions as NPM states ranges
of the track correction, rather than distinct values.
In particular, the track correction Lc at switches and crossings requires some
additional modeling effort as the correction does not apply for the entire
(and arbitrary) length of a railway section, but just to a finite length of 10 m.
For both, LA,eq and LmaxM or LmaxF calculations, an additional railway section
of 10 m length has to be entered at the location of each switch or crossing
having the same emission as the neighboring railway sections, but with a track
correction of Lc=6 dB. Further, the following rules regarding it‘s geometry
apply:
•
with LA,eq calculations: The additional railway section representing a
switch or a crossing replaces by its length the continuous railway track. In
other words, the 10 m section cannot be drawn on top of the existing railway track as this would cause additional ray paths. Thus, a single railway
segment needs to be broken into three peaces resulting in a single section
of 10 m length in between two other sections (see chapter 11.10 in the
manual „Introduction to CadnaA“).
•
with LmaxM or LmaxF calculations: In this case, the additional railway section representing a switch or crossing can be entered on top of the continuous railway track. Deactivate the option "Extrapolate trains to 1/2
length on both sides of rail" (see chapter 6.2.11.3).
CadnaA - Reference Manual
Application of the track
correction
 Examples
\02_Sources\Railway\
NPM 96\10 m switch
correction.cna
208
2
Source Position
2
Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
The source heights with respect to the octave band centre frequency are listed on the following table (approximative):
Partial Source
Octave band centre frequency
(Hz)
63
125
250
500
1000
2000
4000
2
1.5
0.8
0.3
0.4
0.5
0.6
Rails
Wheels
Engine etc.
(Diesel power trains)
Curve screech
Carriages, wagon
(primarily goods trains)
Braking
Source Position on the
track centre line
(meters above rail head)
vmax (km/h)
When specifying a track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
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Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
In CadnaA, the following train types are available from the global library
(Tables menu, Libraries (global)|Railway Groups).
Abbreviation
Train Class Name
Npas
N-Pass El
Ngoo
N-Goods El
Nb65
N-B65 Pass El
Nb70
N-B70 Pass El
Nb69
N-B69 Pass El
Sx2
S-X2 Pass El Concr
Spas
S-Pass El Concr
Spaw
S-Pass/W El Wood
Sx10
S-X10 Pass El Concr
Sgod
S-GoodsDi Diesel Concr
Sgoo
S-Goods El Concr
Fsm
F-Sm Pass El Concr
Fsr1
F-Sr1 Pass El Concr
Fgoo
F-Goods mEl Wood
Rgoo
R-Goods mEl Concr
B71t
BM 71 El today maint
B72t
BM 72 El today maint
B73t
BM 73 El today maint
B71i
BM 71 El improved maint
B72i
BM 72 El improved maint
B73i
BM 73 El improved maint
B93D
BM 93 Di
SL79
SL 79 Leddtrikk
Tban
T-bane
T2k
T-2000
X31
X31/32 Contessa
X52
X52-53 Regina
Y31
Y31 Itino

In case those railway groups are not listed on the Tables menu, import
the library „Train Classes“ from Type „Default“ into the global library.
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Train Types
2
210
2
Train Classes and
Penalties
2
Chapter 2 - Sound Sources
2.6.4 Nordic Prediction Method 1996
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.

In the following, the procedure to edit a local train list (with numbers of
trains) is described. To enter a train list in the local library, see chapter
2.6.1 "Common Input Data", section "Number of Trains".
Local Train List
Train Type
The train type is selected from the list Train Types on the
Library (global)|Railway Group (also called „Train Classes“). By this
selection all relevant parameters are specified.
Number of Trains Day/
Evening/Night
Numbers of trains within 24 hours. With the same numbers of trains for time
periods D/E/N the same power level L’wo,i D/E/N results (see also chapter
6.2.11.3).
Speed v (km/h)
relevant speed of trains (km/h)
Length of one train (m)
length l of the respective train class (m)
Emission Lm,E,i (dB)
The emission level (sound power per unit length) L’wo,i for a train class
resulting from the specified parameter is displayed here.
Library with Number of
Trains
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
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Chapter 2 - Sound Sources
2.6.5 CRN
2.6.5
2 211
CRN
The evaluation parameter in CRN („Calculation of Railway Noise“) is the level LAeq,18h in dB(A) /82/.
2
Dialog Railway (for CRN)
The emission parameter is the A-weighted continuous sound pressure level
LAeq,25m at a distance of 25 m from the nearside railhead. It calculates from
the base line sound exposure level SEL in dB(A) at that distance:
•
for rolling railway vehicles (electric locos, cars and wagons):
SEL vehicle  31.2  20lg v  vehicle correction
•
in dB(A)
for diesel locomotives (full power):
SEL vehicle  112.6  10lg v  vehicle correction in dB(A)
where
v: speed (km/h)
vehicle correction: see subsequent section „Train Types & Type Corrections“
and for N number of identical vehicles:
SELtot  SELvehicle  10 lg N in dB(A)
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Emission Parameter
212
2
Chapter 2 - Sound Sources
2.6.5 CRN
This results in the two levels LAeq for Day and Night:
LAeq ,18 h  SELtot  48.1  10 lg N day
2
in dB(A)
LAeq , 6 h  SELtot  43.3  10 lg N night in dB(A)
where

Track Condition
Nday: number of trains during daytime (6 to 24 hours)
Nnight: number of trains during daytime (0 to 6 hours)
The numerical corrections result from the time correction for 18 hours
(10 lg (18*3600s/1s) = 48.1 dB and 6 hours (10 lg (6*3600s/1s) = 43.3
dB.
In case the option „Train Classes and Penalties“ is selected the track
correction can be entered manually.
Type of Track
continuously welded rail
- on concrete
- on wooden sleepers
jointed track, points and crossings
slab track
concrete bridges and viaducts
steel bridges

correction
(dB)
0
0
+2.5
+2
+1
+(4 to 9)
For the time being, CadnaA provides no list box for CRN-specific
track corrections.
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Chapter 2 - Sound Sources
2.6.5 CRN
CRN specifies a ballast correction of -1.5 dB in case the sleepers are
supported by an acoustically absorbing ballast layer (CRN, clause 22 /82/). In
CadnaA the following specifications apply:
•
Option „Ballast“
2
CadnaA applies the correction in the propagation, not in the emission
(i.e. the emission value LAeq,25m is not changing with „Ballast“ on/off).
•
The correction applies to single and several parallel tracks as well. This
means that the CRN-clause regarding the non-relevance of the ballast
correction for single track railways is not considered automatically in
CadnaA, but just in case the option is deactivated.
•
CadnaA does not apply the ballast correction for screened receivers (i.e.
at least one or more barriers are intersecting the ray path).

The CRN specification to not apply the ballast correction „for a
locomotive on power“ (must read: „... on/under full power“) has to be
ensured by the user by deactivating the option „Ballast“ in this case.
With this option active the „correction for angle of view“ in CRN occurs according to chart 8 (in opposite to chart 7 for other types of trains /82/).
CadnaA applies this correction in the emission value LAeq,25m.
Option „Diesel locomotive
full power“
Based on the track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
vmax (km/h)
The source height in CRN is the height of the nearside railhead. The default
height in CadnaA is 0.6 m relative above ground (see dialog Geometry).
Geometry
For diesel locomotives at full power, however, it is at 4 m above the nearside
railhead. In CadnaA, with the option „Diesel locomotive full power“ activated, 4 m are automatically added to the height specified on dialog Geometry.
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2
Train Types & Type
Corrections
2
Chapter 2 - Sound Sources
2.6.5 CRN
In CadnaA, the following types of train and type corrections are available.

The data of the CRN-specific train classes is not available via the local
or global libraries, but coded internally.
Train Types CRN /82/
Abbr.
Train Class Name
Corr.
dB(A)
Abbr.
Train Class Name
Corr.
dB(A)
Mk1
British Rail MkI
14.8
C43
Class 43
18
Mk2
British Rail MkII
14.8
C47
Class 47
16.6
GwEx
Gatwick Express
16.7
C56
Class 56
16.6
C421
Class 421 EMU
10.8
C59
Class 59
16.6
C422
Class 422 EMU
10.8
C60
Class 60
16.6
LUnA
London Undergr-A Stock
12.9
C73
Class 73
14.8
LUnT
London Undergr-Tube stock
7.1
C86
Class 86
14.8
Mk3
British Rail MkIII
6
C87
Class 87
14.8
Mk4
British Rail MkIV
6
C90
Class 90
14.8
C319
Class 319 EMU
11.3
C91
Class 91
14.8
C465
Class 465 EMU
8.4
C20F
Class 20 Full Power
C466
Class 466 EMU
8.4
C31F
Class 31 Full Power
0
C165
Class 165 DMU
7
C33F
Class 33 Full Power
0
C166
Class 166 DMU
7
C37F
Class 37 Full Power
0
MML
Manchester Metrolink LRV
15.8
C43F
Class 43 (HST) Full Power
0
SYST
South Yorkshire Supertram
14.9
C47F
Class 47 Full Power
0
2XTW
2 axle tank wagon
12
C56F
Class 56 Full Power
0
4XTW
4 axle tank wagon
15
C59F
Class 59 Full Power
0
MGRC
Merry Go Round Coal Hopper
8
C60F
Class 60 Full Power
0
FL
Freightliner
7.5
C390
Pendolino Brittanico
8.7
7.7
C20
Class 20
14.8
C220
Voyager
C31
Class 31
16.6
C221
Voyager (tilting)
C33
Class 33
14.8
C170
Turbostar
C37
Class 37
16.6
0
6
7.6
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Chapter 2 - Sound Sources
2.6.5 CRN
Train Types from DEFRAreport /86/
Abbr.
Train Class Name
Corr.
dB(A)
Abbr.
Train Class Name
Corr.
dB(A)
C168
168 Turbostar DMU
7.6
C450M
450 Desiro EMU (M)
C170n
170 Turbostar DMU - new
7.6
C450T
450 Desiro EMU (T)
6
C175
175 Coradia DMU
7.6
C458M
458 Juniper EMU (M)
7.6
C180
180 Coradia DMU
7.6
C458T
458 Juniper EMU (T)
C220n
220 Voyager DMU - new
7.6
C460M
460 Gatwick Juniper EMU (M)
C221n
221 Voyager DMU - new
7.6
C460T
460 Gatwick Juniper EMU (T)
6
C323M
323 EMU (M)
8.7
KQA_l
KQA loaded Pocket wagon
15
C323T
323 EMU (T)
6
C332M
332 Heathrow Express EMU (M)
8.7
6
7.6
KQA_e
KQA empty Pocket wagon
17.5
7.6
C92
Class 92 locomotive Dual
voltage electric
16.6
6
C332T
332 Heathrow Express EMU (T)
BAA
BAA wagon, Steel carrier, 4 axle
15.2
C333M
333 EMU (M)
7.6
BBA_l
BBA wagon loaded, Steel
carrier, 4 axle
13.4
C333T
333 EMU (T)
6
BBA_e
BBA wagon empty, Steel carrier, 4
axle
16.1
C334M
334 Juniper EMU (M)
7.6
BDA_e
BDA wagon empty, Bolster 4 axle
10.8
C334T
334 Juniper EMU (T)
6
BZA_l
BZA wagon loaded, Steel
carrier, 4 axle
11.8
C350M
350 Desiro EMU (M)
8.7
MEA_e
MEA wagon empty, Box
mineral, 2 axle
5.6
C350T
350 Desiro EMU (T)
6
TDA_l
TDA wagon loaded, Tank, 4 axle
17.8
C357M
357 Electrostar EMU (M)
7.6
TEB_l
TEB wagon loaded, Tank, 4 axle
20.2
C357T
357 Electrostar EMU (T)
6
TIA_l
TIA wagon loaded, Tank, 2 axle
17.8
C375M
375 Electrostar EMU (M)
7.6
HTA_l
HTA wagon loaded, Hopper, 4
axle
7.1
C375T
375 Electrostar EMU (T)
6
HTA_e
HTA wagon empty, Hopper, 4
axle
10.4
C377M
377 Electrostar EMU (M)
7.6
C66
Class 66 rolling, Diesel
locomotive
C377T
377 Electrostar EMU (T)
6
C66F
Class 66 on-power, Diesel
locomotive
C390Mn
390 Pendolino Britannico (M) new
7.6
C67
Class 67 rolling, Diesel
locomotive
C390Tn
390 Pendolino Britannico (T) new
6
C67F
Class 67 on-power, Diesel
locomotive
C444M
444 Desiro EMU (M)
8.7
C444T
444 Desiro EMU (T)
6
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13
-13.4
7.4
-10.8
2
216
2
Train Classes and
Penalties
2
Chapter 2 - Sound Sources
2.6.5 CRN
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.

In the following, the procedure to edit a local train list (with numbers of
trains) is described. To enter a train list in the local library, see chapter
2.6.1 "Common Input Data", section "Number of Trains".
Local Train List
Train Type
The train type is selected from the list „Type“. By this selection all relevant
parameters are specified.
Number of Vehicles
numbers of trains for Day/Evening/Night
Speed v (km/h)
relevant speed of trains (km/h)
Type Correction (dB)
type correction for this train type
Emission LA25,i (dB)
The emission level LA25,i for train class i resulting from the specified
parameter is displayed here.
Library with Number
of Trains
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
CadnaA - Reference Manual
Chapter 2 - Sound Sources
2.6.6 SRM II
2.6.6
SRM II
The calculation method SRM II is part of the „Recommended interim computation
methods“ according to ANNEX II of the EC-Environmental Noise Directive /121/. The
implementation of SRM II in CADNAA refers, therefore, primarily to the procedure
described in the so-called EU-Interim Report /2/ and the EC-Recommendation L 212/49
/114/, and not to the original Dutch procedure /87/.
The Dutch calculation method SRM II („Standaardrekenmethode 2“)
calculates in octave band width and splits up the source into 2 or 4 subsources, located at different heights depending on the train category.
Dialog Railway (for SRM II): spectrum is linear,
sum-level is A-weighted („Tot-A“).
Already within the calculation of emission, the portions of braking or not
braking trains are distinguished. The emission level per unit length in octave
band i is calculated by:

Eh
/ 10
Eh
/ 10 
LhE ,i  10 lg  n  10 nb ,i ,c   n  10 br ,i ,c  in dB/m
c 1
 c 1


2 217
Since the „Number of Vehicles“ D/E/N refer to each daily period (and
not per hour) the emission level LE also refers to that period.
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218
2
2
Chapter 2 - Sound Sources
2.6.6 SRM II
where
n
is the number of train categories using the railway line under consideration,
Enbh ,i , c
is the emission term for non-braking units for train in each train category
(c = 1 to n), in octave band i,
h
br , i , c
E
is the emission term for braking units for train in each train category
(c = 1 to n), in octave band i,
and at assessment height h (h = {0; 0.5; 2; 4; 5} m, dependent on the train category).
The emission terms E calculate from:
•
for braking trains:
Ebrh , i , c  abrh , i , c  bbrh ,i , c logVbr , c  10 lg Qbr ,c  Cbb ,imc in dB
•
for non-braking trains:
Enbh ,i , c  aih, c  bih, c logVc  10 lg Qc  Cbb ,imc
in dB
where:
aih, c , bih, c :
emission terms for train category c in non-braking conditions,
for octave band i, at height h (dB)
abrh ,i , c , bbrh ,i ,c : emission terms for train category c in braking conditions,
for octave band i, at height h (dB)
Qc:
mean number of non-braking units of the railway vehicle category concerned (h-1)
Qbr,c:
Vc:
Vbr,c:
bb:
m:
Cbb,i,m:
mean number of braking units of the railway vehicle category concerned (h-1)
mean speed of passing non-braking railway vehicles (km/h)
mean speed of passing braking railway vehicles (km/h)
type of track/condition of the railway tracks (-)
estimation of the occurrence of track disconnection (-)
correction for to track discontinuities and rail roughness (dB)
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Chapter 2 - Sound Sources
2.6.6 SRM II
The existing categories provided in the Dutch emission database are differ by
propulsion system and wheel brake system as follows:
Category
Train Classes
2
Train description
1
Block braked passenger trains
2
Disc braked and block braked passenger trains
3
Disc braked passenger trains
4
Block braked freight trains
5
Block braked diesel trains
6
Diesel trains with disc brakes
7
Disc braked urban subway and rapid tram trains
8
Disc braked InterCity and slow trains
9
Disc braked and block braked high speed trains
10
Provisionally reserved for high speed trains of the ICE-3 (M) (HST East) type
The next figure shows side views of the train categories and specifies the
number of individual units (i.e. locos, carriages or cars). One unit of any given
category determines the sound emission. In the case of the trains drawn, the
locomotives, carriages or cars act as individual units. In case of integrated
passenger trains (category 9), each connected section (i.e. a railcar or a
carriage) is regarded as a single unit.
SRM II-specific train categories (in brackets: number of carriages/cars per unit).
For category 7 a single unit consists of a carriage with 3 bogies (i.e. 6 axles).
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Train Units
220
2
Chapter 2 - Sound Sources
2.6.6 SRM II

2
In SRM II calculation method, the modification of the predefined train
categories („train classes“) with regard to a real train composition with
deviating train length, can just be corrected by using the number of
units (i.e. locos/carriages/cars) within the periods D/E/N, but not by
modifying the train length itself. The train length is not an editable
parameter in SRM II.
Consequently, the figures „Number of Trains“ to be specified in
CadnaA represent the number of individual units (locos/carriages/
cars) within the periods D/E/N. For example, a high speed train of
category 9 having 8 carriages and two railcars (locos) has to entered as
C09: 8
C09r: 2
With ten trains of this type passing during the daily period the input figures for column „Day“ would be:
C09: 80
C09r: 20
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Chapter 2 - Sound Sources
2.6.6 SRM II
Emission Indices a, b
octave band with centre frequency [Hz]
category
index code
1
2
3
3 motor
63
125
250
500
1k
2k
4k
8k
1
2
3
4
5
6
7
8
a
20
55
86
86
46
33
40
29
b
19
8
0
3
26
32
25
24
a
51
76
91
84
46
15
24
36
b
5
0
0
7
26
41
33
20
39
a, v < 60 km/h
54
50
66
86
68
68
45
a, v >= 60 km/h
36
15
66
68
51
51
27
21
b, v < 60 km/h
0
10
10
0
10
10
20
20
b, v >= 60 km/h
10
30
10
10
20
20
30
30
a, v < 60 km/h
72
88
85
51
62
54
25
15
a, v >= 60 km/h
72
35
50
68
9
71
7
-3
b, v < 60 km/h
-10
-10
0
20
10
20
30
30
b, v >= 60 km/h
-10
20
20
10
40
10
40
40
4
a
30
74
91
72
49
36
52
52
b
15
0
0
12
25
31
20
13
5
a, v < 60 km/h
41
90
89
76
59
58
51
40
a, v >= 60 km/h
41
72
89
94
76
58
51
40
b, v < 60 km/h
10
-10
0
10
20
20
20
20
b, v >= 60 km/h
10
0
0
0
10
20
20
20
5 diesel
a
88
95
107
113
109
104
98
91
b
-10
-10
-10
-10
-10
-10
-10
-10
6
a, v < 60 km/h
54
50
66
86
68
68
45
39
a, v >= 60 km/h
36
15
66
68
51
51
27
21
b, v < 60 km/h
0
10
10
0
10
10
20
20
6 motor
7
8
b, v >= 60 km/h
10
30
10
10
20
20
30
30
a, v < 60 km/h
72
88
85
51
62
54
25
15
a, v >= 60 km/h
72
35
50
68
9
71
7
-3
b, v < 60 km/h
-10
-10
0
20
10
20
30
30
b, v >= 60 km/h
-10
20
20
10
40
10
40
40
a
56
62
53
57
37
36
41
38
23
b
2
7
18
18
31
30
25
a
31
62
87
81
55
35
39
35
b
15
5
0
6
19
28
23
19
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2
Chapter 2 - Sound Sources
2.6.6 SRM II
Emission Indices for
category 9
octave band with centre frequency [Hz]
category
2
index code
63
125
250
500
1k
2k
4k
8k
1
2
3
4
5
6
7
8
71
railcar (=loco)
9, 0 m
9, 2 m
9, 4 m
9, 5 m
a
7
14
57
52
57
66
47
b
27
28
12
18
18
15
21
5
a
9
10
1
41
8
17
0
23
b
26
28
36
22
37
34
39
24
a
5
11
13
56
-27
-19
-37
-12
b
27
28
31
15
50
47
53
36
a
11
18
28
28
-50
-41
-84
-34
b
25
26
25
25
59
56
73
45
67
pushed/pulled units (=cars)
9, 0 m
9, 2 m
9, 4 m
9, 5 m
a
3
10
57
50
53
62
43
b
27
28
12
18
18
15
21
5
a
3
10
57
46
47
55
37
61
b
27
28
12
18
18
15
21
5
a
1
8
54
40
40
49
30
54
b
27
28
12
18
18
15
21
5
a
3
10
54
0
0
0
0
0
b
27
28
12
0
0
0
0
0
Braking Correction
octave band
i
Cbrake.i.c(in dB)
cat = 1, 4, 5
cat =2
cat = 7
cat = 3, 6, 8, 9
1
-20
-20
-8
-20
2
-20
-20
-7
-20
3
-20
-20
-20
-20
4
-2
0
-20
-20
5
2
1
-20
-20
6
3
2
-20
-20
7
8
5
-20
-20
8
9
5
-5
-20
cat: Train Category
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2.6.6 SRM II
The correction factor Cbb,i as a function of structures above station
compounds or railway track condition (bb) and octave band (i) is:
octave
band
i
Superstructure bb
(Track Condition)
2
Cbb,i (in dB)
bb=1
bb=2
bb=3
bb=4
bb=5
bb=6
bb=7
bb=8
concrete
sleepers
in gravel
wooden
sleepers
in gravel
gravel
blocks
blocks
and
gravel
contr. rail
fixation
contr. rail
fixation +
gravel
poured in
railway
lines
1
0
1
1
6
6
-
6
5
2
0
1
3
8
8
-
1
4
3
0
1
3
7
8
-
0
3
4
0
5
7
10
9
-
0
6
5
0
2
4
8
2
-
0
2
6
0
1
2
5
1
-
0
1
7
0
1
3
4
1
-
0
0
8
0
1
4
0
1
-
0
0
Besides the track condition a roughness correction is applied which is a function of track disconnections. The wheel roughness depends on the type of
brake system as a function of the wavelength (radiated frequency is speed related).

The model of roughness correction applied in the original SRM II
method is not dealt with here as it not included in the calculation of
emission in both 2003/613/EC and in CadnaA.
The following types of disconnections are available:
•
•
•
•
Disconnections
jointless rails
rails with joints
2 switches per 100 m
> 2 switches per 100 m
SRM II indicates the following maximum speeds per category:
Speed (km/h)
category
1
2
3
4
5
6
7
8
9
10
v [km/h]
140
160
140
100
140
120
100
160
300
330
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Chapter 2 - Sound Sources
2.6.6 SRM II
These train type specific speed limits are, however, not implemented in
CadnaA for the time being.
2
When specifying a track-relevant maximum speed vmax the speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
Local Train List
Train Type
The train type is selected from the list Train Types on the
Library (global)|Railway Group (also called „Train Classes“). By this
selection all relevant parameters are specified.
Number of Trains Day/
Evening/Night
number of units/vehicles D/E/N. For calculations for mixed evaluation
parameters (such as Lden) see chapter 6.2.11.5 "SRM II".
Speed v (km/h)
relevant speed of trains (km/h)
Percentage of breaking
vehicles
percentage of all vehicles of a train category to be considered as braking
vehicles

Library with Number
of Trains
The emission level LAE is not displayed in the dialog Train Class, but
on the dialog Railroad (as not all correction factors are known with the
dialog Train Class).
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
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Chapter 2 - Sound Sources
2.6.7 NMPB-Fer 1996
2.6.7
NMPB-Fer 1996
Note - No printed guideline is available describing the NMPB-Fer 1996 method applied in
France to railway traffic. This method, called „NMPB-Fer“, is a calculation procedure
implemented only in the former French sound propagation software MITHRA using a emission data set provided by the French national railway institution SNCF. Thus, there is no
detailed documentation on the NMPB-Fer emission model available here.
This option determines what source height is used in the calculation
(attribute TRAM):
•
option activated: The source height is at 0.05 m above the railhead for all
frequencies.
•
option deactivated: The source height is at 0.8 m above the railhead for
frequencies f <= 500 Hz, and at 0.05 m for frequencies f > 500 Hz.
This input box is just available when option „Tram“ is activated. The
specified ground factor G (0<=G<=1, attribute BABS) is used provided the
option „Railways are absorbing (G==1)“ on tab „Ground Absorption“ is activated (see chapter 6.2.7).
In case the option „tram“ is deactivated gravel-ballast is assumed.

With mixed traffic of normal trains and trams on the same track, either
have to be modeled by distinct railway objects.
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Ground Absorption
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2.6.7 NMPB-Fer 1996
Emission Lw’
unweighted (linear) sound power level per unit length (1 meter) and per octave (for periods Day/Evening/Night)
Total-A
A-weighted sum level per period
vmax (km/h)
When specifying a track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
Train Classes and
Penalties
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.

The emission data for calculation according to NMPB-Fer is available
from a file provided to customers separately.
For import of NMPB-Fer specific train classes (format „Mithra Trains“) see
chapter 7.2.14 "Special Formats".
Type of Track
Track Correction (dB): The entered value will be added to the emission spectrum (for all octaves).
Local Train List
Provided the train classes for NMPB-Fer have been imported the local train
list can be edited.
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2.6.7 NMPB-Fer 1996
The train type is selected from the list Train Types on the Library
(local)|Railway Group (also called „Train Classes“). By this selection all relevant parameters are specified.
Train Type
Numbers of trains or units/vehicles during each period. With the same
numbers for time periods D/E/N the same power level L’w,i D/E/N results
(see also chapter 6.2.11.6).
Number of Trains Day/
Evening/Night
relevant speed of trains (in km/h)
Speed v (km/h)
The emission level (sound power per unit length) L’w,i for a train class
resulting from the specified parameter is displayed here.
Emission Lw,i (dB)
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
Library with Number
of Trains
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Chapter 2 - Sound Sources
2.6.7 NMPB-Fer 1996
2
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Chapter 2 - Sound Sources
2.6.8 NMPB-Fer 2008
2.6.8
NMPB-Fer 2008
2
Dialog Railway (for NMPB-Fer 2008): spectrum is linear,
sum-level is A-weighted („Tot-A“).
unweighted (linear) sound power level per unit length (1 meter) and per thirdoctave (for periods Day/Evening/Night)
Emission Lw’
A-weighted sum level per period
Total-A
When specifying a track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
vmax (km/h)
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.
Train Classes and
Penalties
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Chapter 2 - Sound Sources
2.6.8 NMPB-Fer 2008

2
The emission data for calculation according to NMPB-Fer 2008 is available from a separate XML-file containing the relevant train classes.
For import of NMPB-Fer 2008 specific train classes (format „NMPB08
Trains“) see chapter 7.2.14 "Special Formats".
Type of Track
Track Correction (dB): The entered value will be added to the emission
spectrum (for all octaves).
Slab Track (Gs=0)
With this option active, a ground factor Gs=0 is used for the track area. With
the option inactive, the ground factor is Gs=1 (i.e. with ballast).
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2.6.8 NMPB-Fer 2008
Provided the train classes for NMPB-Fer 2008 have been imported the local
train list can be edited.
Local Train List
2
The train type is selected from the list Train Types on the Library
(local)|Railway Group (also called „Train Classes“). By this selection all relevant parameters are specified.
Train Type
Numbers of trains during each period. With the same numbers of trains for
time periods D/E/N the same power level L’w,i D/E/N results (see also
chapter 6.2.11.7).
Number of Trains Day/
Evening/Night
relevant speed of trains (in km/h)
Speed v (km/h)
The emission level (sound power per unit length) L’w,i for a train class
resulting from the specified parameter is displayed here.
Emission Lw,i (dB)
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
Library with Number
of Trains
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2
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Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
2.6.9
2 233
CNOSSOS-EU (Railway)
The emission parameter in CNOSSOS-EU /16/ is the A-weighted longterm average sound pressure level for Day, Evening and Night period,
computed by summation over all frequencies:
L Aeq,LT  10  lg 10
Le q ,T ,i Ai 
i 1
dB  A
where
Ai: A-weighting correction according to IEC 61672-1
i: frequency band index (octaves 125 to 4000 Hz)
T: time period corresponding to Day, Evening or Night
The noise emission of a traffic flow on each track is represented by two
source lines, at 0.5 m (h=1) and 4.0 m (h=2) height above the railhead,
characterized by its directional sound power level per meter and frequency
band (i). That sound power level is the energetic sum of all contributions
from all vehicles (t) passing by on the track type (j). These contributions are:
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2.6.9 CNOSSOS-EU (Railway)
•
•
•
•
from all vehicle types (t)
at their different speeds (s)
under the particular running conditions (constant speed) (c)
for each physical source type (rolling, impact, squeal, traction,
aerodynamic and additional effects sources such as - for example - bridge
noise) (p)
using
 X

L W',e q,T ,dir ,i  10lg  10 Lw ',eq ,l in e, x /10 
 x 1

dB/m
LW',eq,line,x is the x-th directional sound power per metre for a source line of
one combination of t, s, c, p on each j-th track section. Assuming a steady
flow of Q vehicles per hour at an average speed v, an average equivalent number of Q/v vehicles per unit length are passing by. The level LW',eq,line results
from:
 Q 
L W',eq,line,i  ,    L W,0,dir,i  ,   10lg 

 1000  
dB/m
For each specific source the directional sound power is obtained from:
L W,0,dir,i   ,    L W,0,i   L W,dir,vert ,i  L W,dir,hor,i
where
LW,dir,vert,i vertical directivity correction, function of angle 
LW,dir,hor,i horizontal directivity correction, function of angle 

In the CNOSSOS-EU railway noise model, the input data for the
calculation are expressed in 1/3 octave bands (50 Hz - 10 kHz), while
the final emission is stated in octave bands (63 Hz - 8 kHz).
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2.6.9 CNOSSOS-EU (Railway)
The different physical source types and their heights above railhead:
No.
Physical Source Type
Source Height
above Railhead
•
2
0.5 m
1
rolling noise (including not only rail and track base vibration
and wheel vibration, but also, where present, superstructure
noise of the freight vehicles)
2
traction noise
3
aerodynamic noise
4
impact noise (from crossings, switches and junctions)
0.5 m
5
squeal noise
0.5 m
6
noise due to additional effects such as bridges and viaducts
0.5 m
separate sound
power spectra at
0.5 m (source A)
and at 4 m height
(source B)
4m
The rolling noise is split into four essential compounds:
•
•
•
Source Types
Rolling Noise
wheel roughness,
rail roughness,
vehicle transfer function to the wheels and to the superstructure (vessels)
and
track transfer function.
CNOSSOS-EU states that traction noise is modeled for two conditions only:
constant speed (also to be used at deceleration and acceleration) and idling. In
the appendix G, table G-5 /16/, however, just emission data for „idling“ is
given. For this reason, the data for deceleration and acceleration were taken
from the MS-Excel-files provided with the CNOSSOS-EU project. All four
traction noise states are available on the Railway: Train Class dialog (see
below): constant speed, accelerating, decelerating, and idling.
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2
Aerodynamic/Impact/
Squeal Noise, Bridges
and Viaducts
Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
see below
Specification of
Emission
Emission L‘w
The emission parameter in CNOSSOS-EU is unweighted sound power level
per unit length in third-octaves (for periods D/E/N) /16/.
Total-A
A-weighted sum level per period
vmax (km/h)
When specifying a track-relevant maximum speed vmax the train speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
Source Height
When specifying L‘w as emission parameter the source height will be at 0.5 m
above railhead (see figure 2.3.a in /16/). The default height of the railhead
above ground is 0.6 m (see dialog Geometry via Railway dialog).
Train Classes and
Penalties
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.
 Examples\
Note that there are no CNOSSOS-EU specific locos, cars/wagons, or train
compositions available by default. These have first to be defined or imported
from an external file (*.dat) using the Library-Manager (see chapter 12.7),
either to the local or the global library of railway classes (see chapter 2.6.12
"Train Class Libraries").
02_Sources\Railway\train
classes for CNOSSOS-EU

The train classes to be used with CNOSSOS-EU are provided by
DataKustik „as is“ referring to the documentation of the CNOSSOSEU project. The equivalence rail source data is not part of the
commission directive /16/. DataKustik refuses, therefore, any liability
for the final correctness of the provided datasets.
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2.6.9 CNOSSOS-EU (Railway)

The objects listed on the local list of train types (designation starting
with „ZZ_...“) are train compositions not being usable in conjunction
with CNOSSOS-EU. In CadnaA, train compositions are always
displayed independent of the railway standard selected.
The track correction LH,TR,i is available for seven types of tracks i (in octaves,
see table G-3, appendix G of /16/):
Attribute Value FBNR
1
BS Mono-block Sleeper / Soft Pad
2
BM Mono-block Sleeper / Med. Pad
3
BH Mono-block Sleeper / Hard Pad
4
BS Bi-block Sleeper / Soft Pad
5
BM Bi-block Sleeper / Med. Pad
6
BH Bi-block Sleeper / Hard Pad
7
BH Wooden Sleeper
Type of Railhead Roughness
E EN ISO 3095:2013 (Well maintained and very smooth)
M Average network (Normally maintained smooth)
For the further types of railhead roughness mentioned CNOSSOS-EU
/16/ no values are given in the associated appendix G („N Not well
maintained“, „B Not maintained and bad condition“).
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Type of Track
Type of Track
The correction for rail roughness Lr,TR,i is available for two types (in octaves,
see table G-1, appendix G of /16/):

2
Railhead Roughness
238
2
Noise Reduction at Rail
2
Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
No noise reduction measures at the rail are selectable in CadnaA for the time
being due to missing data.

Wheel Roughness
Though CNOSSOS-EU /16/ mentions several noise reduction
measures at the rail (e.g. rail damper, low barrier, absorber plate on slab
track, embedded rail) no values are given in the associated appendix G,
table G-3 („no measure“ only).
The correction for wheel roughness Lr,VEH,i is available for three types (in
octaves, see table G-1, appendix G of /16/):
Type of Wheel Roughness
Cast iron tread brake
Composite brake
Disk brake

Bridge
The setting for wheel roughness applies to CNOSSOS-EU railway
classes and is, therefore, not selectable on the Railway dialog (see chapter 2.6.12, section "Application CNOSSOS-EU").
The following options to select the coefficients Cbridge for structural radiation
are available (not frequency dependent):
Attribute
Value DBRI
Type
Cbridge (dB)
0
(no bridge)
0
1
Predominantly concrete or masonry bridges
with any trackform
1
2
Predominantly steel bridges with ballasted track
4
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Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
With activation of this option the correction for curved tracks will be
considered based on the following curvature ranges (not frequency
dependent):
Curvature Range
Radius of Curvature (m)
2
Correction (dB)
< 300 m
8
300-500 m
5
>= 500 m
0
According to CNOSSOS-EU /16/, squeal contribution shall be applied on
railway track sections where the radius is within the ranges mentioned above
for at least a 50 m length of track.
Specify the number of rail joints per 100 m track length. The coefficients
LR,IMPACT,i for impact noise is given in octaves based on wavelength (see table
G-4, appendix G of /16/). In order to obtain the roughness level Lr the given
wavelength () spectrum is converted into a frequency (f) spectrum by f = v/
, where v is the train speed in km/h. The roughness spectrum as a function
of frequency shifts along the frequency axis for different speeds.
Rail Joints (1/100 m)
 n 
L R,IM PACT ,i  L R ,IMPACTSIN GLE ,i  10 lg  i 
 0.01 
where
LR,IMPACT-SINGLE,i impact roughness level for a single impact per 100 m (see table G-4)
joint density
ni
With this option active, a ground factor Gs=0 is used for the track area. With
the option inactive, the ground factor is Gs=1 (i.e. with ballast).
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Aerodynamic Noise
2
Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
Aerodynamic noise is only considered at speeds above 200 km/h. The aerodynamic noise contribution is given as a function of speed (for source heights
h1=0.5 m and h2=4.0 m above railhead):
v 
LW ,0 ,i  LW , 0,1,i v0    1 ,i  lg 
 v0 
v 
LW ,0,i  LW ,0 ,2 ,i v 0    2 ,i  lg 
 v0 
where
v0
LW,0,1,i
LW,0,2,i
1,i
2,i
reference speed 300 km/h
reference sound power for sources at 0.5 m height
reference sound power for sources at 4.0 heights
coefficient for sources at 0.5 m height (1,i = 50)
coefficient for sources at 4.0 m height (2,i = 50)
Respective values for LW,0,1 and LW,0,2 are given in octaves in table G-6,
appendix G of /16/.
Other railway-related
noise sources
CNOSSOS-EU states that various other railway-related noise sources like depots, loading/unloading areas, stations, bells, station loudspeakers, etc. can be
present and that these sources shall be modeled, if relevant, by industrial
noise sources.
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Chapter 2 - Sound Sources
2.6.9 CNOSSOS-EU (Railway)
In order to select CNOSSOS-EU specific locos, cars, or train compositions
these need to be defined in the local or global library (see chapter 2.6.12
"Train Class Libraries") or to be imported (see preceding section „Train
Classes and Penalties“). Afterwards the train classes or train compositions
will be listed on the local train list.
Local Train List
The train type is selected from the list Train Types on the Library
(local)|Railway Group (also called „Train Classes“). By this selection all relevant parameters are specified.
Train Type
numbers of trains or units/vehicles during each period D/E/N. If the
number of trains is given per hour, these values have to be multiplied by the
number of hours D/E/N respectively.
Number of Trains
relevant speed of trains (km/h)
Speed v (km/h)
selectable states: constant speed, accelerating, decelerating, idling
Traction Noise States
The emission level (sound power per unit length) L’w,i for a train class or
train composition resulting from the specified parameter is displayed here.
Emission Lw,i (dB)
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
Library with Number
of Trains
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2.6.9 CNOSSOS-EU (Railway)
2
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Chapter 2 - Sound Sources
2.6.10 FTA / FRA
2.6.10
FTA / FRA
2
Dialog Railway (for FTA/FRA)
The emission parameter according to FTA/FRA is the A-weighted
equivalent continuous sound pressure level Leq,50ft at 50 feet (15.24 m)
distance from the railway’s axis /91//92/. For a single train class, it calculates
from the sound exposure level SELi,50ft in dB(A) of sub-source i:
 len
SELi ,50 ft  SELref i  10 lg
 len
 ref
where


  K lg v

v
i
 ref



i
SELref: reference sound exposure level for sub-source i
len: length of train or car/loco, in ft. (internally converted to m)
lenref: reference length for sub-source i, in ft. (internally converted to m)
K: speed factor
v: speed, in mph (internally converted to km/h)
vref: reference speed for sub-source i, in mph (internally converted to km/h)
The total level SELtot for all sub-sources n of a single train class is:
 n

SELtot  10 lg 10 SELi / 10 
 i 1

The level Leq,50ft for a single type of train results from (per hour):
Leq ,50 ft  SELtot  10 lg
N
 CThrottle  CTrack
3600
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Chapter 2 - Sound Sources
2.6.10 FTA / FRA
where
N: number of trains per hour
CThrottle: throttle correction (for FTA sources only)
with the throttle correction CThrottle (T: throttle setting):
2
0
CThrottle  
2T  5
for T  6
for T  6
The total level Leq,50ft,tot for all train types j on a track is:
 m L
/ 10 
Leq ,50 ft , tot  10 lg 10 eq , 50 ft , j 

 j 1
Track Correction
Attribute Value
FBNR
1
2
3
4
Type of Track
CTrack
(dB)
0
5
3
4
(normal)
jointed track
embedded track on grade
aerial structure w/ slab track
vmax (km/h)
When specifying a track-relevant maximum speed vmax the speed will be
adjusted if necessary. In the calculation the smaller of both values is used.
Type of Trains
The table on the next page lists all FTA/FRA train types. The following
abbreviations for the sub-source types apply:
Abbreviation
Type of Sub-Source
HSWH
High Speed, Wheel-Rail Interaction
HSPR
High Speed, Propulsion
HSAE
High Speed, Wheel Region - Aerodynamic
High Speed, Train Nose - Aerodynamic
High Speed, Pantograph - Aerodynamic
LOCO
locomotive source
CAR
all other types of vehicles (cars, coaches)
HORN
warning horns
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Chapter 2 - Sound Sources
2.6.10 FTA / FRA
Train Types accord. to FRA report (2005) and FTA report (2006), revised
FTA train types in bold (as of 2015, see footnotes):
Application
Type
Name
Source
Height
(ft)
Source
Height
(m)
FTA/FRA
FRA_HS_EL_LOC
HighSpeed Electric
Locomotive
1
3
1
FTA/FRA
FRA_HS_EL_CAR
HighSpeed Electric
Car
FTA/FRA
FRA_HS_FF_LOC
HighSpeed Fossil Fuel
Locomotive
Type of Trains (cont.)
SELref
dB(A)
lenref
(m)
vref
(km/
h)
SpeedFactor
K
Source
Type
0.30
85
193.2
0.91
75
21.3
144.8
28
HSWH
144.8
15
0.30
85
193.2
144.8
HSPR
28
HSWH
HSWH
1
0.30
85
193.2
144.8
20
10
3.05
83
22.3
32.2
10
HSPR
FTA/FRA
FRA_HS_FF_CAR
HighSpeed Fossil Fuel
Car
1
0.30
85
193.2
144.8
20
HSWH
FTA/FRA
FRA_HS_EMU_LOC
HighSpeed EMU
Locomotive
1
0.30
91
193.2
144.8
20
HSWH
FTA/FRA
FRA_HS_EMU_CAR
HighSpeed EMU Car
1
0.30
91
193.2
144.8
20
HSWH
FTA/FRA
FRA_VHS_EL_LOC
VeryHighSpeed
Electric Loc
1
0.30
91
193.2
145
20
HSWH
5
1.52
89
193.2
289.7
60
HSAE
10
3.05
89
22.3
289.7
60
HSAE
12
3.66
86
22.3
32.2
0
HSPR
15
4.57
86
-
289.7
60
HSAE
VeryHighSpeed
Electric Car
1
0.30
91
193.2
145
20
HSWH
5
1.52
89
193.2
289.7
60
HSAE
FTA/FRA
FRA_VHS_EL_CAR
FTA/FRA
FRA_CONV_FRE_LOC
Conventional Freight
Locomotive
10
3.05
97
27.4
64.4
10
LOCO
FTA/FRA
FRA_CONV_FRE_CAR
Conventional Freight
Car
1
0.30
100
609.6
64.4
20
CAR
FTA/FRA
FRA_CONV_PASS_LOC
Conventional
Passenger Loco
10
3.05
94
18.2
64.4
10
LOCO
FTA/FRA
FRA_CONV_PASS_CAR
Conventional
Passenger Coach
1
0.30
94
152.4
64.4
20
CAR
FTA/FRA
FRA_HORN
Horn
12
3.66
114
-
0
0
HORN
FTA/FRA
FTA_COMM_LOC_DE
Conv. Commuter
Locomotive,
Diesel-Electric
8
2.44
92
-
80.5
-10
LOCO
FTA/FRA
FTA_COMM_LOC_EL
*1)
Conv. Commuter
Locomotive, Electric
2
0.61
90
-
80.5
-10
LOCO
FTA/FRA
FTA15_COMM_LOC
_EL *1)
Conv. Commuter
Locomotive, Electric
2
0.61
90
-
80.5
10
LOCO
FTA/FRA
FTA_COMM_DMU
*2)
Conv. Commuter
Diesel Multiple Unit
2
0.61
85
-
80.5
-10
LOCO
FTA/FRA
FTA15_COMM_DMU
*2)
Conv. Commuter
Diesel Multiple Unit
2
0.61
85
-
80.5
0
LOCO
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Type of Trains (cont.)
2
FTA/FRA
FTA_COMM_HRN
Conv. Commuter
Horn
12
3.66
110
-
0
0
HORN
FTA/FRA
FTA_COMM_CAR
Conv. Commuter Car
1
0.30
82
-
80.5
20
CAR
FTA/FRA
FTA_AGT_ST
Conv. AGT - Steel
Wheel
1
0.30
80
-
80.5
20
CAR
FTA/FRA
FTA_AGT_RU
Conv. AGT - Rubber
Wheel
1
0.30
78
-
80.5
20
CAR
FTA/FRA
FTA_HORN
Horn
12
3.66
113
-
-
0
HORN
footnotes:
*1) The FTA train class FTA_COMM_LOC_EL (Conv. Commuter Locomotive, Electric) uses
an incorrect speed factor K=-10, resulting from an data transfer error in the first implementation
of FTA in CadnaA. Instead, the train class FTA15_COMM_LOC_EL uses the correct speed
factor K=10 corresponding with the value in the FTA-report /91/.
*2) The FTA train class FTA_COMM_DMU (Conv. Commuter Diesel Multiple Unit) uses an
incorrect speed factor K=-10, resulting from an data transfer error in the first implementation of
FTA in CadnaA. Instead, the class FTA15_COMM_DMU uses the correct speed factor K=0
corresponding with the value in the FTA-report /91/.
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2.6.10 FTA / FRA
Train Types accord. to FRA-report, revised edition 2012:
Application
Type
Name
FTA/FRA
FRA12_HS_VHS_EL_LOC
HS & VHS Electric
Locomotive
FTA/FRA
FTA/FRA
FRA12_HS_VHS_EL_CAR
FRA12_HS_VHS_EMU_LOC
Type of Trains (cont.)
Source
Height
(ft)
Source
Height
(m)
SELref
dB(A)
lenref
(m)
vref
(km/
h)
SpeedFactor
K
Source
Type
1
0.30
91
193.2
144.8
20
HSWH
5
1.52
89
193.2
289.7
60
HSAE
10
3.05
89
22.3
289.7
60
HSAE
12
3.66
86
22.3
-
-
HSPR
15
4.57
86
-
289.7
60
HSAE
HS & VHS Electric
Car
1
0.30
91
193.2
144.8
20
HSWH
5
1.52
89
193.2
289.7
60
HSAE
HS & VHS EMU
Locomotive
1
0.30
91
193.2
144.8
20
HSWH
2
0.61
86
193.2
-
-
HSPR
5
1.52
89
193.2
289.7
60
HSAE
10
3.05
89
22.3
289.7
60
HSAE
15
4.57
86
-
289.7
60
HSAE
0.30
91
193.2
144.8
20
HSWH
FTA/FRA
FRA12_HS_VHS_EMU_CAR
HS & VHS EMU Car
1
5
1.52
89
193.2
289.7
60
HSAE
FTA/FRA
FRA12_HS_GT_LOC
HS Gas Turbine Locomotive
1
0.30
91
193.2
144.8
20
HSWH
10
3.05
83
22.3
32.2
10
HSPR
FTA/FRA
FRA12_HS_GT_CAR
HS Gas Turbine Car
1
0.30
91
193.2
144.8
20
HSWH
FTA/FRA
FRA12_CONV_FRE_LOC
Conventional Freight
Locomotive
10
3.05
97
27.4
64.4
10
LOCO
FTA/FRA
FRA12_CONV_FRE_CAR
Conventional Freight
Car
1
0.30
100
609.6
64.4
20
CAR
FTA/FRA
FRA12_CONV_PASS_LOC
Conventional
Passeng. Locomotive
10
3.05
92
18.2
80.5
-10
LOCO
FTA/FRA
FRA12_CONV_PASS_CAR
Conventional
Passenger Coach
1
0.30
82
25.9
80.5
20
CAR
FTA/FRA
FRA12_HORN
Horn
12
3.66
113
-
-
-
HORN

For the time being, the train class MAGLEV (magnetic levitation train)
is not available in CadnaA as a source height of -5 feet (i.e. below
ground) cannot be selected.
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Default Lengths for
FRA Train Classes
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2.6.10 FTA / FRA
In FTA report, the default length is the standard length being used in
conjunction with the number of vehicles (locos or cars) to correct for the final emission per unit length. When introducing the respective traffic figures
for vehicle types (locos, cars) the number of units of this length are concerned. The default length applied by CadnaA for each vehicle type are:
Type
Name
DefaultLength (m)
DefaultLength (ft)
FRA_HS_EL_LOC
HighSpeed Electric Locomotive
21.34
70
FRA_HS_EL_CAR
HighSpeed Electric Car
18.59
61
FRA_HS_FF_LOC
HighSpeed Fossil Fuel Locomotive
22.25
73
FRA_HS_FF_CAR
HighSpeed Fossil Fuel Car
18.59
61
FRA_HS_EMU_LOC
HighSpeed EMU Locomotive
22.25
73
FRA_HS_EMU_CAR
HighSpeed EMU Car
18.59
61
FRA_VHS_EL_LOC
VeryHighSpeed Electric Loc
22.25
73
FRA_VHS_EL_CAR
VeryHighSpeed Electric Car
18.59
61
FRA_CONV_FRE_LOC
Conventional Freight Locomotive
27.43
90
FRA_CONV_FRE_CAR
Conventional Freight Car
20.72
68
FRA_CONV_PASS_LOC
Conventional Passenger Locomotive
18.28
60
FRA_CONV_PASS_CAR
Conventional Passenger Coach
18.59
61
FRA_HORN
Horn
-
-
FRA12_HS_VHS_EL_LOC
HS & VHS Electric Locomotive
22.25
73
FRA12_HS_VHS_EL_CAR
HS & VHS Electric Car
18.59
61
FRA12_HS_VHS_EMU_LOC
HS & VHS EMU Locomotive
22.25
73
FRA12_HS_VHS_EMU_CAR
HS & VHS EMU Car
18.59
61
FRA12_HS_GT_LOC
HS Gas Turbine Locomotive
22.25
73
FRA12_HS_GT_CAR
HS Gas Turbine Car
18.59
61
FRA12_CONV_FRE_LOC
Conventional Freight Locomotive
27.43
90
FRA12_CONV_FRE_CAR
Conventional Freight Car
20.72
68
FRA12_CONV_PASS_LOC
Conventional Passeng. Locomotive
18.28
60
FRA12_CONV_PASS_CAR
Conventional Passenger Coach
25.90
85
FRA12_HORN
Horn
-
-
In contrary, FTA report does not state a default length. The emission in FTA
is per car/loco. Thus, the default lengths in each respective train class are zero.
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2.6.10 FTA / FRA
With this option activated, the types of trains and train classes, numbers of
trains and corrections, can be edited locally, or an existing list with number of
trains can be selected. CadnaA will automatically calculate the emission level
from the specified values.

Train Classes and
Penalties
2
In the following, the procedure to edit a local train list (with numbers of
trains) is described. To enter a train list in the local library, see chapter
2.6.1 "Common Input Data", section "Number of Trains".
Local Train List
The train type is selected from the list Train Types on the
Library (global)|Railway Group (also called „Train Classes“). By this selection all relevant parameters, such as train length and speed or percentage
of disc brakes, are specified.
Train Type
Numbers of vehicles/units D/N (E not relevant). In case the amount is given
by vehicles/units per hour, this values have to be multiplied by 15 to obtain
the figure for Day and by 9 for Night (for FTA/FRA).
Number of Trains Day/
Evening/Night
relevant speed of trains (km/h)
Speed v (km/h)
length l of vehicle/unit, deviating from default length (m)
Train Length (m)
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2.6.10 FTA / FRA
As locos and cars are different train classes in FTA/FRA, an entire train consists, normally, of at least two types of train classes. Regarding the input of the
length, however, both classes - locos and cars - have to be distinguished.
Example 1: A steel-wheeled electric train with 2 power cars and 8 passenger
coaches is defined using the FRA-railway group „VHS Very High-Speed“
and the following traffic data:
•
number of trains: 60 during Daytime (4 trains per hour)
In this case, the length entered for locos as well as for cars corresponds to either default lengths (check box „Length“ on dialog „Train Class“ is
deactivated). So, the number of vehicles to be entered for each category is:
•
•
number of locos: 120 during Daytime (8 per hour)
number of cars: 480 during Daytime (32 per hour)
Example 2 corresponds with example 1 regarding the number of trains. The
number of vehicles, however, is entered in a different way.
As the noise emitted by the pantograph of the locos is linked to the number
of locos, the two locos in each train cannot be entered as a single source of
type FRA_VHS_EL_LOC while doubling its length. This would lead to a
wrong emission as the pantograph’s aerodynamic emission is per vehicle and
not per length. So, the service numbers for locos have to be kept.
For the cars, however, the 8 passenger coaches per train could be counted as
a single unit with a length of 8 * car length (8 * 18.59 m = 148.72 m). In this
case, the number of locos and car compositions passing by are:
•
•
number of locos: 120 during Daytime (8 per hour)
number of cars: 60 during Daytime (4 per hour)
Both ways to specify the emission lead to the same emission level.
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2.6.10 FTA / FRA
The FTA-model applies a correction for the throttle setting with dieselpowered locos and Diesel Multiple Units (DMUs) only (see table 6-4, FTAreport). In CadnaA, throttle setting is applied to all sources of type LOCO
instead. Consequently, the user has to ensure that the throttle is zero for all
other FTA-loco-types besides the two mentioned above.
Throttle setting
The emission level LeqL(1h) for a train class resulting from the specified
parameter is displayed here.
Emission Lm,E,i (dB)
see chapter 2.6.1 "Common Input Data", section "Number of Trains"
Library with Number
of Trains
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2.6.10 FTA / FRA
2
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2.6.11 Further Procedures for Railway Noise
2.6.11
2 253
Further Procedures for Railway Noise
Information on the following standards or guidelines for railroad noise can
be found in the German version of the CadnaA reference manual:
•
ONR 305011, Austria
•
DIN 18005 (1987), Germany
•
Semibel, Switzerland
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2.6.11 Further Procedures for Railway Noise
2
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2.6.12 Train Class Libraries
2.6.12
Train Class Libraries
The global library for train classes (via Tables|Libraries (global)| Railway
Groups) provides the emission data of various guideline-specific train classes
with their parameters. This library is accessed when editing a local train list
(with numbers of trains) on the dialog Railway, but also when compiling a
train list in the local library (Tables|Libraries (local)|Numbers of
Trains).
This global library of train classes can be edited for a number of railway
guidelines and extended by the user. As with any global library it is available
in any CadnaA project without any further import operation.
Table Train Classes (or Railway Groups) from the global library
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Local Library
2
Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
In order to use a global train class in a project the required data sets have to
be copied to the local library first. Alternatively, the train classes are selectable
from the global library via list box „Train Type“ on dialog Railway:Train
Class.
This depends, however, on the calculation guideline selected as some
calculation methods just use the global train classes (e.g. Schall03 (1990),
Schall03 (2014), SRMII, ONR 305011, Nordic Prediction Method, FTA/
FRA) while for others the global train classes have to be copied to the local
library (e.g. NMPB-Fer 1996, NMPB-Fer 2008, CNOSSOS-EU). For further
guidelines the guideline-specific train classes are just coded in CadnaA
internally and can, therefore, not be edited (e.g. Semibel, CRN, SRM II).
Inserting a new train class
In order to define a new train class insert a new line into the local or global
library (via the context menu command Insert before/after). With a doubleclick on the new row the edit dialog of the new train class opens.
Application
Depending on the guideline selected the dialog will be adjusted. The option
„Application“ acts as a filter. For example, with the application „Schall 03
(1990)“ selected here, these train classes are available from the list box on the
dialog Railway:Train Class, in case Schall 03 (1990) has been selected on
the dialog Calculation|Configuration, tab „Country“.
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2.6.12 Train Class Libraries
The data box may contain any kind of text.
Name
This data box must respect the rules applying to CadnaA objects (i.e. no
blanks or special characters or symbols, besides the underscore „_“, starting
by letters).
Train Type/Short Name
Some calculation methods for railway noise offer to set up user-defined trains
composed of locomotives and wagons/cars (e.g. ONR 305011,
Schall 03 (2014), NMPB-Fer 1996/2008, FTA/FRA). When the option
„Train Composition“ is selected from the list box, user-defined trains can be
edited using the existing train types/classes. Enter in the list the number and
the train type/class available from the library of train classes by double
clicking in column „Train Type“ and select the train class from the dialog
Train Composition.
Train Composition
Train composition for FTA/FRA:
train composed of 2 locos and 8 cars
Enter also a name and a short name for train type (see above). When
selecting this train composition via the dialog Railroad the entered short
name/name will be displayed on the list box „Train Type“. A train
composition may consist of 11 lines (data sets) at the most.
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2
Application Schall 03
(1990)
2
Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
With the application of Schall 03 the following input data is required to
define a new train class:
•
•
•
•
•
Name and Short Name
Percentage of Disc Brakes p (%)
Speed v (km/h)
Length of one (single) train l (m)
Type Correction Dfz (dB), alternatively selectable form the list box.
Dialog Library:Train Class: new train class for Schall 03 (1990)
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2.6.12 Train Class Libraries
The procedure Schall03 (2014) /26/ makes use of relative spectra which are
added to the specified A-weighted sum level. In case measured (absolute)
spectra are to be used enter zero for the A-weighted sum level.
Application
Schall03 (2014)
2
The following input data for a new train class are required:
•
•
•
type of brake
reference speed (in km/h), usually v0=100 km/h
reference number of axles
For each relevant sub-source m (first column, see table 5, Schall03 (2014)) the
relevant octave band level spectrum has to be entered. To this end, enter x
for each relevant source height in column „valid“. This activates this subsource. Enter a space to deactivate this sub-source.
Dialog Library|Train Class: entering a new train class for Schall03-2014
In the local list „Number of Trains“ (on Railway dialog) the following train
classes are listed:
•
•
individual locomotives, cars, carriages, and all trains according to table 4,
Schall03 (2014), and
train compositions as defined in the global library of train classes,
indicated by the prefix „ZZ_“.
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Application Nordic
Prediction Method
2
Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
Nordic Prediction Method requires spectra of parameters a and b to define a
new train class. The following input data is required to define a new train
class:
•
•
•
Name and Short Name
Diesel engine yes/no
octave band spectrum for parameters a and b
To enter the spectrum click into the respective cell of the table.
Dialog Library:Train Class: new train class
for Nordic Prediction Method
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Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
NMPB-Fer 1996 requires an octave band emission spectrum to define a new
train class. The following additional input data is required:
•
•
•
•
•

Name and Train Type/Short Name
Variation of v: equation describing the variation of emission vs. speed (e.g.
30 * log10 (v/vref))
Reference Speed vref (km/h)
number of bogies: applies to loco and cars (also several cars)
options „Tram“ or „Pneu“ on/off
In case both options „Tram“ or „Pneu“ are activated the source will
radiate omni-directional, compared to non-pneu trams and other
ordinary trains using a pre-defined directivity.
To enter the spectrum click into the respective cell of the table
Dialog Library:Train Class: new train class
for NMBP-Fer 1996
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Application NMPB-Fer
1996
2
262
2
Application NMPB-Fer
2008
2
Sub-Source Table
Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
NMPB-Fer 2008 requires multiple third-octave band emission spectrum at
several heights (at 0.0, 0.5, and 4.0 m) to define a new train class. The
following additional input data is required:
•
Name and Train Type/Short Name
•
options „Tram“ or „Pneu“
NMPB-Fer 2008 requires to define sub-sources for a new train class at a single or several heights. In this case, in column „valid“ a letter x is entered to
activate that respective row. Type space to deactivate a row.
•
vref (km/h): reference speed
•
Slope: variation of emission vs. speed (e.g. „30“ for 30*log10(v/vref))
•
Num: number of bogies, applies to loco and cars (also several cars)
•
third-octave band emission spectrum per sub-source
To enter the data click into the respective cell of the table.
Dialog Library:Train Class: new train class
for NMBP-Fer 2008
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Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
FTA/FRA requires to define sub-sources for a new train class at a single or
several heights. In this case, in column „valid“ a letter x is entered to activate
that respective row. Type space to deactivate a row.
Application FTA/FRA
2
Dialog Library:Train Class: new train class for FTA/FRA
Besides the sound exposure level SEL the FRA/FTA-emission model
considers:
•
•
•
•
Emission Model
default length (m), used for length correction
reference length len_ref (m), used for emission correction
reference speed S_ref (km/h) and speed factor K
sub-source type (see below)
The FRA-source heights for all types of sub-sources result from tables 5-2
and E-1 in the FRA-report. As the source height specified for horns from either tables differ (12 vs. 13 ft), just the height of 12 ft has been considered in
the emission table.
As far as source height with FTA-source heights are concerned, CadnaA applies a height of 12 ft for horns, of 8 ft for diesel-electric-locos and 2 ft for all
other types of sources (see table 6-5 in the FTA-report). The horns as point
sources do not require a default length.
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Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
Default Source Lengths
The default source length for FRA-train classes is the physical length of each
vehicle (loco, car/wagon), irrespective what reference length len_ref is used
to specify the source emission (see chapter 2.6.10). As FTA-report evaluates
the emission per car/loco this value is not relevant in this case.
Source Types
The following source types are used (see FRA-report, tables 5-2 and E-1, and
FTA-report, table 6-4):
2
HSWH
HSPR
HSAE
LOCO
CAR
HORN
Option „Length“
High Speed Source - Wheel-Rail Interaction
High Speed Source - Propulsion
High Speed Source - Aerodynamic (with different heights)
locomotive source
all other types of vehicles (cars, coaches)
warning horns
With FTA/FRA train compositions ensure that the option "Length" in each
train class is deactivated. This will cause the total length being the sum of all
locos and cars. Entering a length for train compositions is not required, nor
recommended.
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2.6.12 Train Class Libraries
In conjunction with CNOSSOS-EU, it requires first to import or define train
classes and/or train compositions in the local or global library of train classes.
Subsequently, these will be selectable in the local train list (see chapter 2.6.9)
or in the table Number of Trains (see chapter 2.6.1 "Common Input Data",
section "Number of Trains").
Train compositions make use of previously defined train classes, e.g. a freight
train could be defined based a train class for a single electric loco and a number - say 16 - freight cars, thus making up an entire train.
Dialog Library: Train Class: new train class for CNOSSOS-EU
With the application of CNOSSOS-EU the following input data is required
to define a new train class:
•
•
•
Name and Train Type, Short Name
Maximum Speed vmax (km/h)
Reference Number of Axles
and (see next page):
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Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
Parameter
Options
Vehicle
Type
o other
d1 Diesel locomotive (c. 800 kW)
d2 Diesel locomotive (c. 2200 kW)
d3 Diesel multiple unit
e1 Electric locomotive
e2 Electric multiple unit
a generic freight vehicle (car)
Diesel loc/RENFE Dloco/1155kW
Diesel loc/NS6400 Dloco/1180kW
Diesel loc/TKOJ JT42CWR/Class66/2.2MW
with
traction
correction
w. superstructure
correction
+
+
+
+
+
-
+
Remarks
„o other“: any other kind
of cars, besides freight cars
(i.e. maintenance vehicles
etc.)
(caption for columns left:
+ = is included
- = is not included)
Break Type
min
max
c Cast iron tread brake
k Composite brake
n Disk brake
-
Contact
Filter
min
max
Axle load 50 kN - wheel diameter 360 mm
Axle load 50 kN - wheel diameter 680 mm
Axle load 50 kN - wheel diameter 920 mm
Axle load 25 kN - wheel diameter 920 mm
Axle load 100 kN - wheel diameter 920 mm
approx. CRN conditions
-
Wheel
Diameter
min
max
920 mm
840 mm
680 mm
1200 mm
wheel diameter 360 mm
not available due to missing data in table G-2 of
appendix G /16/
Wheel
Measure
n no measure
no further options
provided in /16/
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Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
The editing of new train classes for the following guidelines is described just
in the German version of the CadnaA reference manual:
•
ONR 305011
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Application for further
guidelines
2
268
2
Chapter 2 - Sound Sources
2.6.12 Train Class Libraries
2
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Chapter 2 - Sound Sources
2.6.13 Traffic-Count Calculator
2.6.13
Traffic-Count Calculator
The Traffic-Count Calculator dialog on the Extras menu enables to
redistribute the actual numbers of trains or of flight movements (i.e. traffic
counts) for the time periods Day/Evening/Night.
2
Especially with calculations according to the EC-Directive on Environmental
Noise the prevailing numbers of trains or flights for Day and Night may be
redistributed to the three time periods Day/Evening/Night. The variables
for the traffic counts of the three time periods are: nd for Day, ne for
Evening, and nn for Night.
The redistribution can be applied to:
•
•
•
all activated objects „Railway“,
all lists for „Numbers of Trains“ (and consequently for all objects „Railway“ referencing a respective train list), and
all activated objects „Air Route“.
In the example above, the actual traffic counts of the local train lists for Day
and Night will be redistributed, resulting in Evening counts being 25% of the
Day, plus 20% of the Night. Therefore, the original traffic counts are reduced
for the Day to 75% and for the Night to 80%.
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2
Option „Delete AllZero-Lines“
2
Chapter 2 - Sound Sources
2.6.13 Traffic-Count Calculator
When this option is active, all data sets of the selected object type/s
containing no data (empty or zero lines) will be deleted upon the next
recalculation. This option ensures that non-valid traffic data (e.g. from import
operations) is kept and exported afterwards.
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Chapter 2 - Sound Sources
2.7 Parking Lots
2.7
Parking Lots
The sound emission of parking lots can be calculated either
•
according to RLS-90, or
•
according to the parking lot study by the Bavarian Environmental Agency
LfU (several editions available), or
•
according to the Swiss standard SN 640 578:2006-07.
2
For the calculation of sound propagation, the German road noise standard
RLS-90 or the selected guideline for industrial sources may be applied. Depending on selected calculation method the dialog Parking Lot is showing
the respective input boxes.
Dialog Parking Lot
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Chapter 2 - Sound Sources
2.7 Parking Lots
Dialog Options
Type
2
The selected type of the parking lot determines whether the road noise standard RLS-90 or the selected guideline for industrial sources is used for calculation of sound propagation („public (RLS)“ or „private (Industry)“).

Calc emission according
to ...
Both, the LfU studies, as well as the Swiss standard SN 640 578: 200607 just represent an emission model, but not a propagation model.
The following options are available:
•
•
•
•
•
•
RLS-90 /17/
LfU study 1993 /49/
LfU study 1995 precise/approximative /50/
LfU study 2003 separate/non-separate /51/
LfU study 2007 separate/non-separate /52/
SN 640578 /66/

In LfU-study 1995 two types of procedures are described, an „exact“
and an „approximative“ procedure. Using the exact procedure requires
the noise from search and passage of vehicles to be modeled using the
object „Road“ while the approximative procedure makes use of a global
estimate.

With respect to the LfU-studies 2003 and 2007 the term „separated“
refers to the separate modeling of the noise by parking events and of
the noise from search and passage of cars. In this case, the noise from
search and passage of cars has to be modeled by separate roads. In case
the so-called „combined“ procedures are used (no „separate“ in the
designation) the noise emission modeled includes the correction KD to
consider the noise by search and passage of vehicles.
Further details on the calculation of emission according to RLS-90, the most
recent edition of LfU parking lot study and according to SN 640 578 are given in chapters 2.7.1 to 2.7.3.
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2.7 Parking Lots
•
input of the emission level L*m,E (dBA) for the time periods Day/Evening/Night
•
display of the A-weighted sound power level PWL (dBA) for the time
periods Day/Evening/Night
For calculations according to RLS-90, the editions 1993 and 1995 of the LfU
study, and the Swiss Standard SN 640 578 the number of lots is always the
relevant reference quantity. In the LfU study 2007, besides the number of
lots, also other reference quantities are used (e.g. net sales floor area).
Input/Display of Emission
2
Counts, Parking Spaces
First, select the type of parking lot via the file selector symbol
. Make
sure that the select numbers of events refer to the selected guideline. Upon
closing the table Parking Lot:Number of Events the reference quantity is
shown in the input box to the right of „Reference Quantity“ with LfU-Study
2007 selected.
•
Number of Parking Spaces: Enter here the number of parking spaces or any
other figure in units of the reference quantity.
•
Number of Spaces per Reference Quantity f: In this box the parking lot type specific figure f according to the table Parking Lot:Number of Events is
displayed.
Assuming the reference quantity is „1 m² net sales floor area“ and f=0.04,
this means that 25 m² net sales floor area is required each single parking
space (0.04 * 25 = 1).
•
Example
Events per Hour and Parking Space: In this box the parking lot type specific
number of events per hour and parking lot or reference quantity resp. is
displayed (as resulting from the table Parking Lot:Number of Events).
The number of movements for Day is also used for Evening.
The penalty Dp (accord. to RLS-90 and SN 640578) or Kpa (accord. to LfU
studies) can be entered or the type of parking lot is selected from the list box
(see chapters 2.7.1 to 2.7.3).
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Penalty for Parking Lot
Type
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2.7 Parking Lots
Option "incl. Interval
Maximum Penalty"
In conjunction with private parking lots activating this option - provided a
LfU study selected - enables to apply the correction for impulsive noise components Ki depending on the type of parking lot. The value displayed is in
this case the sum (Kpa + Ki).
Option "Penalty for Road
Surface"
When using the combined procedure according to LfU study 2007 a
correction KStro is used to take different road surfaces into account (direct input or selection from a list).
Operating Time (min)
With the parking lot type "private (ind)" selected, the operation time (in
minutes) can be entered here for parking lots not constantly operational. The
time specified refers to the time periods D/E/N as specified on the dialog
Configuration, tab „Reference Time“. When this check box is deactivated a
permanent emission is assumed.
Library with Number
of Events
The table Parking Lot:Number of Events can be accessed via the dialog
Parking Lot or from the Tables menu, Libraries (global)|Parking Lot
Movements. The data is saved globally and is thus available for further new
CadnaA projects as well.
2
When editing a new data set enter in box „Ref. Quantity“ an informative text
string. Enter the „Number of Spaces per Ref. Quantity f“ and the „Events
per Hour and Parking Space“ (or per Reference Quantity) for the daily periods Day and Night. The number of events for Day will be used for Evening/
Recreation Time as well. The box „Source“ offers to enter remarks regarding
the data’s origin.
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Chapter 2 - Sound Sources
2.7.1 RLS-90
2.7.1
2 275
RLS-90
The emission value of parking lots in RLS-90 is the mean level L*m,E at 25 m
distance from the center point of the parking lot area with unobstructed
sound propagation /17/:
Emission Value L*m,E
L*m,E = 37 + 10 lg (N * n) + DP
where
N: number of events per parking space and per hour (see below)
n: number of parking spaces on the parking lot or on a part of the parking lot
DP: correction for different types of parking lots

When assessing the number of parking events the approach and
departure of a vehicle is counted as one event each.
If the condition l <= 0,5 s (l: largest dimension of the parking lot (normally a
diagonal), s: distance center point receiver) is not met the parking lot’s area
has to subdivided into partial areas i. In case the parking lot’s area is screened
the condition to fulfill is: l <= 0,8 s.
accord. to RLS-90, table 5:
Type of Parking Lot
Number of Events per
Parking Space and Hour
Number of Events per Parking Space and Hour
Day
(6-22 hours)
Night
(22-6 hours)
park-and-ride parking
0.3
0.06
motorway service area
1.5
0.8

Per default, the number events for period Day are also used for the
period Recreation Time/Evening.
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Parking Lot Type
Chapter 2 - Sound Sources
2.7.1 RLS-90
accord. to RLS-90, table 6:
Parking Lot Type
2
Sound Power Level
PWL
correction Dp in dB
Parking: Auto
0
Parking: Motorcycle
5
Parking: Truck / Bus
10
Sound Power Level PWL in dB(A) for the daily periods Day/Evening/
Recreation results from:
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
2.7.2
LfU-Study (2007)
The A-weighted sound power level is the relevant emission parameter with
the various Bavarian parking lot studies, however, it cannot be specified directly. CadnaA always displays both emission parameters:
•
input of the emission level L*m,E (dBA) for the time periods Day/Evening/Night
•
display of the A-weighted sound power level PWL (dBA) for the time
periods Day/Evening/Night
Emission
For direct input specify the emission level L*m,E (dBA) (individually for the
time periods Day/Evening/Night). The value results from sound power level
PWL (dBA) according to:
Direct Input
The sound power level per unit area PWL“ of parking lots calculates
according to the „combined procedure“ (i.e. including noise from search and
passage of vehicles) according to edition 2007 of the Bavarian parking lot
study using number of events /52/:
Number of Events
where
PWL0 = 63 dB(A), initial sound power level for one movement/h on a Park-and-Ride parking
lot
KPA: penalty for parking lot type
KI: penalty for impulsive noise (just for the combined procedure)
KD: correction for search and passage of vehicles
KStrO: penalty for road surface
B: number of reference quantities B0
N: frequency of movements (movements per reference quantity and hour)
B · N = number of vehicle movements per hour on the parking lot area
S: total area or partial area of the parking lot
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
Applying the „separated procedure“ (i.e. including noise from search and
passage of vehicles) the correction terms KD and KStrO are dropped.
2

The calculation of parking lot emission according to former editions of
the Bavarian parking lot study is not described here. The calculation
according to earlier editions is still provided to ensure downward compatibility.
Parking Lot Type
penalty
KPA
dB
penalty
KI
dB
0
4
- standard shopping trolleys on asphalt
3
4
- standard shopping trolleys on pavement
5
4
- low-noise shopping trolleys on asphalt
3
4
- low-noise shopping trolleys on pavement
3
4
Parking: Nightclub + Discotheque (includes talking noise
and car radios)
4
4
Restaurant
3
4
Fast Food Restaurant
4
4
- Central Bus Terminal (Diesel engine)
10
4
- Central Bus Terminal (natural gas engine)
7
3
Truck Parking
14
3
Parking: Motorcycle
3
4
Type of Parking Lot
Park-and-Ride (includes parking areas near residential districts, visitors’ and employees’ parking areas, parking areas
at the fringe of the city centre)
Parking: Shopping center
Parking: Shopping center
Central Bus Terminal
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
When assessing impulsive noise according to the German regulation
(TALärm /109/) a special time weighting procedure is applied (maximum
level in intervals of 5 seconds). To account for this type of time weighting activate the option „incl. Interval Max. Penalty“. The same penalty for
impulsive noise Ki is applied for the „separated“ (special case) and for the
„combined“ procedure (normal case).
Impulsive Noise
Both procedures described in the LfU study are implemented in CadnaA:
the „combined“ procedure (i.e. including noise from search and passage of
vehicles) and the „separated“ procedure (i.e. without noise from search and
passage of vehicles).
Search/Passage of
Vehicles
The „combined“ procedure (normal case) applies the correction KD due to
search and passage of vehicles:
combined procedure
2
where
f: parking places per reference quantity
B: number of reference quantities (i.e. number of parking spaces, net sales floor area, beds)
with:
When using the separated procedure the noise level resulting from search and
passage of vehicles on the parking lot has to be modeled using the object
„Road“. Either the respective traffic counts are known or have to be estimated for the relevant routes.
At private parking lots (option „private (ind)“ selected), the roads have to be
converted into line sources afterwards to apply the propagation for industrial
sources (see chapter 11.13 in the manual „Introduction to CadnaA“). The
following conversion rule applies:
PWL’ = Lm,E + 19,2 dB
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280
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)

2
Road Surface
According to LfU study 2007 a velocity of 30 km/h has to be used.
When applying the combined procedure the road surface on the parking lot’s
has to be specified in addition.
Penalty for Road Surface
asphalt driving lanes
0
concrete block pavement, gaps < 3 mm
0,5
concrete block pavement, gaps > 3 mm
1,0
water-bound surface (gravel)
2,5
natural stone paving
3,0

Reference Quantity B
KStrO
dB
According to LfU study 2007 the penalty KStrO is not considered with
parking lots at shopping centers with asphalt or paved road surface as
the level increase due to trolley noise is already taken into account in the
penalty KPA for the parking lot type.
In LfU study 2007 the following reference quantities B0 are used:
•
•
•
1 parking place,
1 m² net sales floor area,
1 bed
When calculating the sound power level of several, distinct parking lots using
the same reference quantity (e.g. net sales floor area of a shopping center), the
reference quantity B has to be divided up according to the percentage of the
parking lot areas.
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
•
absolute: In this case, the total number of events per hour has to be
specified. Enter for „Number of Ref. Quantities B“ the value B=1.

A parking lot of type „motorway service area, refueling, cars“ with 100 movements per hour during Day for the following combinations:
•
2
When specifying the absolute number of events/movements, CadnaA
applies the product of the number of reference quantities B and the
movements D/E/N.
When using the separated procedure the same emission level results for
B=1 and N=100 movements/h or B=25 and N=4 movements/h (for
Day):
separated procedure: B=1 with N=100 movements/h and B=25 with N=4 movements/h
(Day) cause the same emission level, LwA,Day = 83 dB(A)
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Example
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
•
When using the combined procedure, however, just the input of B=1 and
N=100 movements/h (Day) generate the correct emission as the correction for search and passage of vehicles is calculated from the number of
movements only:
2
combined procedure: B=1 with N=100 movements/h (Day) and B=25 with N=4
movements/h (Day) cause different emission levels. Just B=1 and N=100 movements/h
(Day) yields the correct emission level (KD=0 dB as f*B<=10)!

As the combined procedure predicts the correction KD due to search
and passage based on the product (f*B), and as the parking lot types
with absolute number of events do not have search and passage passage
events, it follows from B=1 for the correction KD=0 dB.
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
Parking Lot Types
accord. to LfU-Study
2007
Name
Reference Quantity
B0
No. of Spaces/
RefQ
f
Events/h/RefQ
Day
N
Events/h/RefQ
Night
N
park-and-ride parking city
nonchargeable
1 Parking space
1.00
0.300
0.060
park-and-ride parking nonchargeable
1 Parking space
1.00
0.300
0.100
motorway service area, refueling, cars
absolute
1.00
40.000
15.000
motorway service area, refueling,
trucks
absolute
1.00
10.000
6.000
motorway service area, resting, cars
1 Parking space
1.00
3.500
0.700
motorway service area, resting, trucks
1 Parking space
1.00
1.500
0.500
housing estate, underground parking
1 Parking space
1.00
0.150
0.020
housing estate, parking
1 Parking space
1.00
0.400
0.050
discotheque
1m² Net public floor area
0.50
0.020
0.300
consumer market small
1m² Net sales floor area
0.07
0.100
0.000
consumer market big
1m² Net sales floor area
0.07
0.070
0.000
discounter and beverages market
1m² Net sales floor area
0.11
0.170
0.000
white goods market
1m² Net sales floor area
0.04
0.070
0.000
do-it-yourself (DIY) store and
furniture market
1m² Net sales floor area
0.03
0.040
0.000
public house in city
1m² Net public floor area
0.25
0.070
0.020
public house rurally
1m² Net public floor area
0.25
0.120
0.030
Tavern
1m² Net public floor area
0.25
0.100
0.100
Fast Food restaurant
1m² Net public floor area
0.25
0.400
0.150
Drive-In
absolute
1.00
40.000
6.000
hotel (beds <100)
1 Bed
0.50
0.110
0.020
hotel (beds >100)
1 Bed
0.50
0.070
0.010
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Chapter 2 - Sound Sources
2.7.2 LfU-Study (2007)
car park city chargeable (max 2 h)
1 Parking space
1.00
1.000
0.030
car park city chargeable
1 Parking space
1.00
0.500
0.010
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Chapter 2 - Sound Sources
2.7.3 SN 640 578
2.7.3
SN 640 578
The A-weighted sound power level LW,i of a parking lot according to
SN 640 578 (edition 2006-07) calculates from /66/:
Emission
where
LW,PVi: sound power level per movement and hour of a parking lot type with area i, in dB(A)
dMi: traffic correction, in dB
In CadnaA, an initial sound power level of LW,PV=66 dB(A) is used in
conjunction with a correction for the type of parking lot KPA (see below):
The traffic correction results from:
where
Bsub area i: number of events on sub-area i per hour (for Day/Night separately)
nsub area i: number of parking spaces on sub-area i
For direct input specify the emission level L*m,E (dBA) (individually for the
time periods Day/Evening/Night). The value results from sound power level
PWL (dBA) according to:
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Direct Input
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Chapter 2 - Sound Sources
2.7.3 SN 640 578
Parking Lot Type
Attribute
Value
PARTNR
2
Parking Lot Type
LW,PV
dB(A)
Correction for
Parking Lot Type
DPA in CadnaA
dB *3)
Level Correction
for Shopping
Trolleys *4)
1
Commercial Traffic
66
0
2
2
Park and Ride
66
0
2
3
Service Provider
66 *1)
0
2
4
Shopping Traffic
67 *1)
1
2
5
Leisure Activities
68 *1) *2)
2
2
6
Residents and Visitors
67 *1)
1
2
7
Waiting and Assembly
Areas
68 *1) *2)
2
2
8
Miscellaneous
67 *1)
1
2
9
Cars
76
10
1
10
Trucks
78
12
-
11
Motorcycles
69
3
-
*1) The sound power level includes noise due to door and hatch slamming.
*2) The sound power level includes noise due to car radios.
*3) with reference to the initial sound power level of LW,PV= 66 dB(A)
*4) The level correction for the use of shopping trolleys has to corrected for in CadnaA manually by the user
via the correction for the parking lot type Dp.
Search/Passage of
Vehicles
When calculating the immission level the noise due to search and passage of
vehicles is accounted for automatically by:
:
:
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Chapter 2 - Sound Sources
2.7.3 SN 640 578
The noise due to the passage of vehicles is modeled using the object „Road“.
According to SN 640 578 a velocity of 30 km/h has to be used.
Passage of Vehicles
The noise due to cars entering and leaving the parking lot is not considered in
CadnaA.
Entry & Exit Noise

The implementation in CadnaA only refers to the modeling of socalled „uncovered parking lots“ according to SN 640 578. The other
noise sources specified in this standard (underground car park, parking
garage) are not implemented.
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2.7.3 SN 640 578
2
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Chapter 2 - Sound Sources
2.8 Pass-By of individual Vehicles
2.8
Pass-By of individual Vehicles
CadnaA offers to calculate for roads, railways, and line sources the time history of the sound pressure level that would result from a single vehicle with a
specified emission passing by, according to the selected standard. The command Pass-By Level in the context menu of those types of line source is
only available if at least one receiver has been inserted.
For example, generating this pass-by level history enables to check:
•
whether the effect of a noise-control device, such as a barrier, would be
sufficient for all affected partial areas, or
•
which noise reduction may be expected by providing a reflecting building
facade with absorbent cladding, or
•
by which amount the sound pressure level resulting from single motor
vehicles traveling by is reduced if - for example - a zone with a speed limit
of 30 km/h is established in an ordinary inner-city street.

2 289
The feature „Pass-By Level“ is not available in conjunction with the
angle-scanning method (see chapter 6.2.2).
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Chapter 2 - Sound Sources
2.8 Pass-By of individual Vehicles
DIALOG OPTIONS
2
Receiver
Select the name of the receiver point where the pass-by level shall be
calculated.
Source Type
The available option depend on the type of object from the context menu of
which the command Pass-By Level was selected.
all object types: Userdefined
The option „user-defined“ is always available (for roads, railways and line
sources). In this case, all parameters can be specified individually.
Subsequently, the source is running along the route with the specified speed
and sound power level.
Object „Road“: light or
heavy
The sound power level of cars („light“) or trucks („heavy“) is determined
based on the speed specified on the dialog Road (see below). The sound
power levels correspond with the specifications in RLS-90 /17/.

Object „Railway“: train
class
The length of the vehicle is not relevant for the calculation of the passby level, but is only used in the animation.
On the list box all train classes from the dialog Railway are listed. When selecting a specific train class the sound power level is calculated according to
the specifications of Schall 03 (1990) /23/ (see below).
Emission/Sound
Power Level
Object „Road“
The sound power level for cars („light“) and trucks („heavy“) calculates from:
 v

LWA 1 car   Lm , E 1000 cars / h   19.2 dB  10 lg cars 
1
/
km
h


 v

LWA 1 Lkw   Lm, E 1000 Lkw / h  19.2 dB  10 lg  Lkw 
 1 km / h 
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Chapter 2 - Sound Sources
2.8 Pass-By of individual Vehicles
On the following table, the sound power level for cars and trucks is given as a
function of the speed are listed addressed to a single vehicle of each category
based on the emission value Lm,E according to RLS-90 (see chapter 2.4.2).
Vehicle
Category
Emission
Parameter
light (car)
heavy (truck)
2
Speed in km/h
30
50
80
100
120
Lm,E
58,5
60,8
64,8
67,2
69,4
LWA
92,5
97,0
103,0
106,4
109,4
Lm,E
71,5
74,3
76,9
-
-
LWA
105,5
110,5
115,1
-
-
Examples:
•
car at 100 km/h: LWA 1 car   67.2  19.2  10 lg100  106.4 dB ( A)
•
truck at 80 km/h: LWA 1 truck   76.9  19.2  10 lg80  115.1 dB ( A)
After selection of a train class the sound power level calculates from:
s
 v 

LWA 1 train   Lm, E 1 train   19.2 dB  Railway Corr  10 lg 
  10 lg 16 h * 3600 
h
 3 .6 

where
•
•
•
•
•
Lm,E: emission level at 25 m from the railway’s axis (according to Schall 03)
19.2 dB: relationship between the emission level Lm,E and the sound power level per unit
length PWL’ (according to Schall 03)
Railway Correction: When the option „Strictly according to Schall 03“ is enabled (see Section 6.2.11.1), a correction of 5 dB is considered. Otherwise, the value entered on tab „Railway“ is used.
v: train speed in km/h
16 h: A time correction is applied as the emission in Schall 03 refers to a time interval of 16
hours. This correction is a constant.
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Thus, the sound power level per unit length LWA’ for a single train with train
length l (m) is:
2
 l 
LWA ' 1 train   LWA 1 train   10 lg 

1 m 
Example
emission of an ICE train with a railway correction of 5 dB:
The sound power levels LWA and LWA’ result from:
 250 
LWA 1 train   50.2  19 .2  5  10 lg 
  47.6  130 .4 dB( A)
 3 .6 
 420 
LWA ' 1 train   130.4  10 lg
  104.2 dB ( A )
1m 
Object „Line Source“
When selecting the command Pass-By Level from the context menu of a
line source, the sound power level can be entered directly after selecting the
option „user-defined“.
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Both, the sampling time and the speed determine the section lengths through
which the fictitious vehicle or the source moves from one location to the
next. A sampling time of 1 s may be sufficient to check for the required calculation time, a value of 0.1 s may be appropriate to represent a level record
showing all level variations due to shielding and reflections.
Sample Time
The direction of traffic can be specified with respect to the direction in which
the road was inserted. „Positive“ (pos) means the driving direction is from
the first to the last point of the geometry, „negative“ (neg) vice versa.
Driving direction
negative/positive
By this option several pass-bys can be simulated consecutively with their level
history getting appended to each other. Keep the dialog Pass-by Level displayed and mark once again the same object or a different one with the right
mouse button and select again Pass-By Level from the context menu. Activate the option „Append to Diagram“ and select for the driving direction
„negative“ or „positive“.
Append to Diagram
By clicking and dragging the mouse arrow inside the diagram with the left
mouse button depressed in a horizontal direction the vehicle symbol will be
moved along the source line in the graphics.
Pass-By Diagram
Alternatively, select a value from the Animation menu. The pass-by then
will start running automatically with the selected speed.
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Auralisation
Chapter 2 - Sound Sources
2.8 Pass-By of individual Vehicles
Hardware requirement: sound card and loudspeaker or headphones
On the menu Auralization|Properties the saved sound file of the relevant
process is opened after selection of a sound type in the list box and is
reproduced - regarding volume - according to the calculated time history of
the pass-by level.
2
3D-Auralisation
By the option „3D-Auralization“ the Doppler effect - when switching from
approach to departure (by „Direction of Motion“ - will be simulated in a realistic way.
Listening direction at
Receiver Point
Automatically to source: viewing directly towards the source (with the shortest distance)
Direction (°)
view at the given angle towards the source, relative to the x-axis
Calibration
Select the desired volume from the list box and adjust the corresponding
playback on your audio device.
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Example
•
Test the Pass-By with a simple arrangement as in the following figure.
 Examples\
02_Sources\
Road\Pass-By.cna
Road with buildings and a receiver
•
Open the context menu by clicking the road axis with the right mouse key
and select the command Pass-By Level.
•
From the list box „Receiver“ select the desired receiver for which the
pass-by level shall be calculated - in our example IP1.
•
In the next box „Source Type“ select „light“.
•
Adjust the sampling interval to 0.1 s.
•
After confirmation with OK the diagram opens with the calculated level’s
time history. The calculation time depends on the complexity of the project.
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2
For a light vehicle calculated level time-history
•
Now move the mouse cursor in the diagram and press the left mouse button. On this position a vertical cursor line appears, whose time and sound
pressure level is indicated in the upper dialog bar and a symbol (black
box) indicates the vehicle’s position on the road in the graphic, in the driving direction on the road.
•
When dragging the cursor line horizontally ins the diagram the vehicle’s
symbol will move along the road.
•
Alternatively, select a value from the Animation menu.
Regarding the vehicle’s position relative to the location of buildings
reflections (increases in level) and shielding effects (reductions in level) can
be realized by respective level changes.
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The level’s time history can be copied to the clipboard to be pasted into other
software (e.g. like MS-Excel or MS-Word), either as sequences of numbers or
as a chart.
•
To this end, activate the Level-Time diagram on dialog Pass-by Level by
clicking onto it. The upper dialog bar gets highlighted. Now copy to the
clipboard by clicking the „Copy“ button (or by pressing the C key).
•
Paste the data into the other software and confirm either graphic or text.
Indicating the vehicle on the road with a symbol (black box)
and in the diagram with a vertical cursor line
•
Check for further options on the Pass-By dialog.
•
Vary the reflection of single buildings by switching them on and off alternately and watching the effect on the level’s time history.
This diagram also facilitates the optimization of barriers, because the effect
of a modification can be assessed immediately. Beyond the mere consideration of time-averaged levels, the pass-by feature offers a tool which enables
to examine and visualize the effects of level-reducing measures on the actual
level.
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Copy the Level’s Time
History
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2.8 Pass-By of individual Vehicles
Video
The pass-by can be recorded as a video using AVI format for replay using any
standard video software (such as Windows Media Player). Click the button
„Video“ to configure the recording options.
Video Options
•
Section: An existing and named section can be selected which is used for
the video output (standard: entire limits). It is useful to define a
calculation area within that section.
•
Option „follow source“: With this option activated the video section follows the moving point source.
•
Scale: Upon activation of the entered scale is used, otherwise the scale
defined in the project (default value 1:1000).
•
Resolution (dpi): When activated and with a value entered, this resolution
is used, otherwise the setting on the main window is used. The larger the
value, the finer the resolution and the greater the file size (default value 75
dpi).
•
Frame rate (fps): default value 15 fps
2

A bitmap used as a background image will not be displayed in the video.
To record a video, a respective compression algorithm (video codec) has to
be specified after having entered a file name.
After confirming with OK the pass-by is calculated and recorded.
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2.9 Optimisable Source
2.9

Optimisable Source
This type of source requires option BPL. BPL stands for „Back-Tracing
of Power Levels“.
2
This object enables to enter an area source the emission of which is
maximized by an optimization procedure. The characteristics of this type of
source are:
•
In the calculation, the area of the optimisable source is segmented into
sub-areas in the same way as with the general area source (see chapter 2.1)
taking into account the receiver distance and screening objects. Each subarea is replaced by a point source.
•
The configuration option on the „Industry“ tab „Obstacles within Area
Sources do not shield“ (see chapter 6.2.9) shall be activated when determining noise quotas using the optimisable source. This will cause screening objects inside the optimisable source’ area not to affect its emission.
•
On the dialog Optimisable Source, switch from Day to Night
depending on what period shall be used in the optimization. The
specified sound power refers to the selected period (sound power level
PWL or sound power level per unit area PWL“).
•
The further input parameters at the bottom of the dialog differ from the
"normal" area source. These parameters are required for the optimization
with respect to the allocation of noise quotas (or noise allotment).
Dialog Options
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Period Day/Night
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Chapter 2 - Sound Sources
2.9 Optimisable Source
Select the daily period which shall be used in optimization (Day or Night).
The specified sound power refers to the selected period.

The optimization procedure in conjunction with noise allotment occurs
in CadnaA for the levels Ld (Day) and/or Ln (Night) only. This means
that mixed level (such as Lden or Lde) cannot be used for an optimization calculation, since the emissions of the partial periods can not be
optimized separately. Therefore, make sure that the levels Ld and Ln are
selected for the first two evaluation parameters on tab „Evaluation
Parameters“ (see chapter 6.2.5).
In case a mixed level is selected as the first evaluation parameter (e.g.
Lde), the optimization occurs, however, for the level Ld. When the optimisable source is converted afterwards into a normal area source, the
receiver level increases by 1.93 dB assuming that the same emission
level Day=Evening/Recreat.Time was specified and, for example, with
13 hours for the Day period, 3 hours for the Night period and a penalty
of 6 dB for the Evening/Recreat.Time (here with Ld=Le=60 dB (A)):
Therefore, when optimizing the daytime level Ld and after having converted the optimisable source into an area source whose emission shall
be - in this example - decreased by 1.93 dB in order to respect the limiting value given as Lde, again assuming the same emission during Day
and Evening/Recreation Time.
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Enter alternatively the sound power level PWL or the the sound power level
per unit area PWL".
Power Level PWL or PWL"
This option is activated by default. In this case, a change in emission cause an
immediate effect.
Option „Apply
immediately"
The usability function assigns a usability value w% to any sound power level
per unit area. The continuous shape of the usability function is approximated
in CadnaA by two straight lines and a salient point.
Salient Point of Usability
Function
Via these input boxes the emission of the optimisable source can be
restricted:
Range PWL",min to
PWL",max
•
PWL",min: This value is the minimum required emission. It is determined
based on the absolutely necessary noise-relevant processes (e.g. a 10-minute truck ride across an area of 1000 m² results in a PWL"= 55 dB(A)).
•
PWL",max: This value is the maximum exploitable emission (depends on
the branch of industry and may be up to 80 dB(A) for industrial installations with permanent truck traffic).
After optimization the slider control bar is at the location of the resulting
emission value the value of which is displayed on the top of the dialog.
This button is no longer effective as the option "Apply immediately" is
always activated.
Button "Apply"
When clicking this button the sound power of the actual optimisable source
is optimized with respect to all active receiver points. In this case, the emission of all further optimisable sources is no changed. To optimize all optimisable sources in a project at once select the command Optimize Area
Sources on the Calculation menu.
Button "Optimize"
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Noise Allotment
Chapter 2 - Sound Sources
2.9 Optimisable Source
CadnaA supports this optimization in a flexible manner without applying a
specific fixed optimization strategy, but by use of user-definable usability
function. The optimization procedure aims at determining the permissible
emissions, ensuring that
2
Usability Function
•
the relevant limiting values at receiver points in the vicinity are respected,
and
•
the intended use of the individual areas is not restricted as far as possible.
In order to achieve this, a usability function is assigned to each area.
The decreasing slope of the function with increasing sound power level
means that a further increase in emission cannot be exploited due to the
intended use. On the other hand, the usability decreases excessively when a
particular emission required for the intended use is further reduced.
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2.9 Optimisable Source
•
•
Power Level PWL" (dBA) at the salient point: The emission value where
the gradient of the usability function changes. A reduction of the power
level by 1 dB below this point results in an even stronger reduction in
usability than the same reduction above the salient point. Enter here the
value that should be "retained" in the optimization (default value: 60
dBA).
Usability K (%) at the salient point (default value: 80%)
Due to this concept the individual requirements can be accounted for in the
maximization /99/. The usability function of CadnaA is approximated by
two lines. This requires three emission values for each partial area as a basis
for the maximization. The usability specified at the turning point determines
the curve and thus the "maximizing strategy". Common data for industrial
areas is:
PWL’’ min
57 dB(A)
Turning Point
80 % / 60 dB(A)
PWL’’ max
65 dB(A)
The bottom part of the edit dialog for the optimisable source contains a
horizontal scroll bar enabling to select an emission value within the range
from min to max like. The current value which is displayed in the dialog
above. For a first test, push the slider to the extreme right, thus selecting the
maximum emission value.
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Calculation
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2.9 Optimisable Source
The most critical receiver points are entered with their relevant limiting levels.
Clicking the calculator icon on the toolbar starts the calculation. If no
receiver turns red either for day, nor for night, this means that the limiting
levels are respected using the maximum value assumed. In this case, no
further reduction of the emission is necessary.
In the calculation, all sources existing in the project - roads, railways, industry
or aircraft noise - are taken into account. By the deactivating objects using
groups (see chapter 14.3) different scenarios can be analyzed. The procedure
described so far is the same as for the calculation of ordinary area sources.
65.0
65.0
(10/10)
(250/10)
70.0
So far, the described procedure does not differ from the calculation of
normal area sources.
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The red color shows that the limiting level is exceeded at a receiver point. In
this case, reduce the emission of the optimisable source with the strongest
noise impact on the relevant receivers in steps.
Manual Optimization
2
CadnaA does not require a new calculation for each step. Double-clicking
the respective optimisable source and shifting the position of the slider will
show the resulting change at the receivers immediately. Depending on the desired strategy, the emission values can be reduced until compliance with the
standard levels is ensured at all receiver points.
Apply this procedure separately for day-time and night-time as required.
Selecting the command Optimize Area Sources on the Calculation menu
causes to start an automatic, iterative reduction of the emission values. It is always the reduction of emission resulting in the smallest decrease of the arearelated usability according to the concept explained above which is carried
out in this step-by-step procedure.
With
Si
area in m² of the ith partial area
wi
area-related usability in % of the ith partial area
the total usability is
w
 wi  S i
 Si
This value is displayed at the beginning and the end of the maximization. After optimization, the position of the horizontal scroll bar represents the emission optimum value and is displayed in the top of the dialog.

The iteration step width is 0.1 dB by default. Alternatively, the iteration
step width can be controlled using a local text block (Name: BPL), for
example, in order to optimize the calculation time. The text DELTA_L=1.0 sets - for example - the iteration step width to 1 dB.
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2.9 Optimisable Source
The result calculated by CadnaA needs not be the best if further aspects, not
included in the usability function, are to be considered. In this case, the automatic optimization is a suitable starting point, whereas manual modifications
of the emission values using the slider enable to further adapt the scenario in
the required way.
see also: chapter 6.2.13 "Optimizable Source Tab"
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Chapter 3 - Obstacles
Chapter 3 - Obstacles
3
In CadnaA, the following types of objects cause a screening effect in the calculation of propagation, depending on the standard or guideline selected for
each noise type:
•
•
•
•
•
•
•
•
building,
cylinder,
barrier,
bridge,
embankment,
ground absorption area,
built-up areas and foliage,
3D-reflector.
The following types of obstacles may also have reflecting properties:
•
•
•
•
building,
cylinder,
barrier,
3D-reflector.
In order to specify the reflectivity of the surfaces of obstacles three options
are available in CadnaA.
Reflection Properties
No reflection is calculated for this object. This is the default setting.
No Reflection
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Chapter 3 - Obstacles
The subsequent options require that on dialog Calculation|Configuration,
tab „Reflection“ (see chapter 6.2.8) at least the reflection order 1 has been
selected.
3
Reflection Loss
Enter the reflection loss in dB due to reflection or click the file selector
symbol to select from a predefined list of surface classifications (resulting
from RLS-90, table 7 /17/)..
Dialog Building: specifying the reflection loss
Absorption Coefficient
Alpha
With this option activated, a single-number value, a formula, or the reference
to an absorption coefficient spectrum (see chapter 12.1 Local and Global Libraries) can be specified.

The reflection loss RL is evaluated from the absorption coefficient
Alpha according to:
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Chapter 3 - Obstacles
3.1 Building
3.1
Building
Buildings are modeled as a sequence of walls raising vertically from the
ground and forming a closed polygon. The floor plan can be of any shape, a
rectangular shape can be enforced however (action/command Force Rectangle, just applies to buildings with four polygon points, see chapter 11.4 in
manual „Introduction to CadnaA“). By default, buildings are modeled without a roof plate, although this is displayed in the 3D-Special view (see chapter
9.14). For sources above roof level the ground attenuation results from the
source height above ground and not above roof (as the roof is not a reflecting
surface).
There are no roof ridges and no gable walls considered by default as the
building is modeled from a series of barriers of the same height and having
no roof („open box“).
In order to include the screening effect by the ridge, it is recommended to enter a barrier along the ridge line inside the building’s floor plan with a height
corresponding to the ridge height (see chapter 3.1.5).
To account for the screening effect by gable walls additional polygon points
of the building polygon are entered (CTRL key). The height is specified using
the option „Height at every Point“ via the dialog Geometry of the building
(see chapter 3.1.5).
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Roof ridge and gable
walls
4
3
Internal Sources
Chapter 3 - Obstacles
3.1 Building
Before starting the calculation, CadnaA performs a consistency check (see
chapter 5.1.1) checking for sources inside the building’s floor plans. If so, a
message will be displayed.
3
Result of the Consistency Check
Ignoring the message (by clicking the „Continue“ button), the building’s
outer walls will be considered as barriers diffracting the sound across the
barrier’s top edge. So, in this case again, the roof is acoustically not existent
by default.

This restriction is due to the procedures in the respective calculation
standard or guidelines, and not a restriction specific to CadnaA.

In order to model the sound radiation from buildings, vertical area
sources are attached to the building’s facade the emission of which can
be specified based on the interior level (see chapter 6.1 in the manual
"Introduction to CadnaA" and see chapter 12.1.2 in this manual).
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Chapter 3 - Obstacles
3.1 Building
Dialog Options
3
Dialog Building
see chapter 4.4.2 in the manual "Introduction to CadnaA"
Name, Memo-Window,
ID, ObjectTree
By default, buildings are not reflecting sound (option „No Reflection“). Selecting one of the options „Reflection Loss“ or „Absorption Coefficient Al-
Reflection Loss/
Absorption Coeff. Alpha
pha“ enables to specify via the respective file selector symbol
either a
reflection type (according to RLS-90 /17/) or to address an absorption spectrum from the local or the global (by SHIFT-clicking) library of absorptions.
In this case, reflections from the building’s surface are taken into account applying the image source method, provided that on tab „Reflection“ (see chapter 6.2.8) in the configuration of calculation at least the first order of
reflection is selected.
see chapter 3.1.1
Option „Residential
Building“
see chapter 3.1.2
Acoustical Transparency
(%)
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Button "Geometry"
Chapter 3 - Obstacles
3.1 Building
Via the button „Geometry“ the building’s height is specified (see chapter 4.2).

3
Buildings lifted from the ground can be entered using the geometry
option „absolute Height/Ground at every Point“. Those „floating“
buildings are also displayed on the 3D-Special view as lifted above
ground. By contrast, in the calculation the ground will be automatically
triangulated to the base line of the building causing a screening effect
below the building. Background of this phenomenon is diffraction
model used by all existing which do not cover screening objects lifted
from the ground. Further, this is due to the normative restriction that by default - no reflective surfaces in the z direction exist besides the
ground.
 Examples\03_Obstacles\Building\Building Height Ground at every
Point.cna
Building floating
above the ground,
defined using the
geometry option
„Height/Ground
at every Point"
Level distribution
on the vertical
grid: The ground
is triangulated to
the base points of
the house causing
a screening effect
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3.1 Building
37
The option „Sources in Buildings/Cylinders do not shield“ is available for industrial sources (see chapter 6.2.9 "Industry Tab").
Sources in Buildings
do not shield
The command Deactivate point objects in buildings (from Extras menu)
offers to deactivate point like objects (e.g. height points, point sources) laying
inside of the building polygons. This feature can be applied after import
operations in order to delete all deactivated objects afterwards using the
command Modify Object (see manual „Introduction to CadnaA“).
Deactivate Point
Objects in Buildings
Further chapters regarding buildings:
•
•
•
•
•
•
•
•
•
command Edit Facades (see chapter 3.1.4)
Defining a roof ridge (see chapter 3.1.5)
command Generate Building (see chapter 3.1.6)
action/command Force Rectangle on the dialog Modify Objects and on
the context menu (see chapter 11.4 , see manual „Introduction to
CadnaA“)
entering receivers along facades (see chapter 5.1, section "Entering receivers at a building’s facade")
Snap Point on Building Facade (see chapter 3.1.3)
Building Evaluation (see chapter 5.4)
Building Noise Map (see chapter 5.4.1)
Import Building Height Points (see chapter 7.2.17)
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3
Chapter 3 - Obstacles
3.1 Building
3
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Chapter 3 - Obstacles
3.1.1 Residential and non-residential Buildings
3.1.1
Residential and non-residential Buildings
By default, a building gets marked as a „Residential Building“. For other types
of buildings this options may be deactivated. When calculating the population
density (using option XL, see chapter 15.4) only the residential buildings are
considered.
Option „Residential
Building“
Residential buildings and non-residential buildings may use different
hatchings.
Graphical Appearance
Residential building and non-residential building with different filling
There are two ways to achieve this:
•
For this, create a second layer of type „Simple“ for the object type „Building“ on the Appearance dialog (on the Options menu, see chapter 9.5)
with a different filling and enter the following expressions: WG_NUM
== 0 (for non-residential buildings) and WG_NUM! = 0 (for residential
buildings).
Dialog Appearance for object type „Building“
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Chapter 3 - Obstacles
3.1.1 Residential and non-residential Buildings
•
Alternative, activate for the object type „Building“ the option „Legacy
Display“ on the Appearance dialog (on the Options menu, see chapter
9.5) and select on the „Fill“ tab the filling type shown below (3rd in the
list):
3
In this case, residential buildings will be displayed with this hatching and
non-residential buildings with a vertical hatching.
Residents
The number of residents is a characteristic of the buildings. The value is
displayed as an integer value, despite figures with decimals result when
calculating the population density (see chapter 15.4).
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3.1.2 Acoustic Transparency (%)
3.1.2
3 11
Acoustic Transparency (%)
The object „Building“ may have a characteristic called „acoustic
transparency“ in %. The default value is 0% which means that the building is
acoustically non-transparent.

3
This option has been implemented based on user request.
Dialog Building, option „acoustic Transparency“
This feature enables to model more or less open structures, e.g., an
arrangement of pipes, tanks and other technical equipment penetrated by
sound. This is modeled using the object „Building“ with a transparency value
addressed.
With an acoustic transparency larger than zero it will be considered in the
calculation of the screening effect that the object is (partially) transparent.
This, however, applies with the calculation procedures VDI 2714/2720 and
ISO 9613-2 only.
For other calculation procedures and source types Industry, Road, Railway
and Aircraft Noise, the option „acoustic transparency“ has no effect unless
the propagation model is based on VDI 2714/2720 or ISO 9613-2. Presently
(as of 2017), the acoustic transparency has an effect - besides the industrial
standards mentioned above - for HJ 2.4 (Industry), Schall03 (2014) and ONR
305011 (both Railway) since they are based on the ISO propagation model.

Use acoustic transparency with VDI 2714/2720 and ISO 9613-2 only.
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ISO propagation model
12
3
Calculation Strategy
Chapter 3 - Obstacles
3.1.2 Acoustic Transparency (%)
The following calculation strategy is applied:
•
3
•
•
•
•
At first it is checked which objects cause diffraction applying the „ribbon
band method“.
An acoustic transparency of X% gives a transmission factor of X/100. If
the sound energy at the receiver is reduced by dE according to the screening calculation, then with a collective transparency of X% the energy (X/
100)*dE is added to the sound energy calculated with transparency zero.
The total degree of transmission for many buildings in path is the product
of all single transmission factors.
A building having no transparency or a barrier (i.e transparency is zero) in
path will cause a total transparency of zero which means that all buildings
are considered non-transparent.
The same rule applies to terrain, i.e. a screening terrain contour (explicit
or triangulated) in path will also cause a total transparency of zero.
At the receiver point two sound contributions are added energetically:
•
•

The first contribution is the diffracted sound over and if necessary
around the arrangement and is calculated as for non-transparent objects.
The second contribution is calculated as direct sound energy, not taking
into account the shielding objects, but multiplying this energy value by the
resulting transmission factor defined above. With direct sound
contribution Edir and the resulting transmission factor , this second contribution is Edir * .
This procedure was implemented due to user demands. It is not
described in any standard or guideline. The depth of an object with
transparency in ray direction has no impact on the calculation result.
The value of the acoustic transparency is considered to be the same for
all directions.
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Chapter 3 - Obstacles
3.1.2 Acoustic Transparency (%)
Examples
The example shows a point source with PWL=100 dB(A), a building and a
receiver. There are three variants defined in the file:
•
variant 1: non-transparent building
•
variant 2: transparent building (acoustic transparency 10%)
•
variant 3: without building
 03_Obstacles\Transparency\Example 1 - without lateral diffraction.cna
3
The calculations for all three variants without lateral diffraction (option Lateral Diffraction „none“ on tab „Industry“, see e.g. chapter 6.2.9.1 "ISO
9613").
Example 1 - without lateral diffraction, variant 2: building transparent
In the three following variants result level is calculated:
•
variant 1: SPL=40.2 dB(A)
•
variant 2: SPL=55.0 dB(A)
•
variant 3: SPL=64.9 dB(A)
From the referenced MS-Excel file the calculation procedure can be studied
leading to these results applying the strategy described above.
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 03_Obstacles\Transparency\Calculation
Example 1 - without lateral diffraction.xlsx
14
3
 03_Obstacles\Transparency\Example 2 - with
lateral diffraction.cna
Chapter 3 - Obstacles
3.1.2 Acoustic Transparency (%)
In this example, the calculations are carried out for all three variants including
lateral diffraction (option Lateral Diffraction „some objects“ on tab „Industry“, see e.g. chapter 6.2.9.1 "ISO 9613".
3
Example 2 - with lateral diffraction, variant 2: building transparent
For the three following variants the following receiver level are calculated (in
variant 2 again with an acoustic transparency of 10%):
•
variant 1: SPL=45.0 dB(A)
•
variant 2: SPL=55.3 dB(A)
•
variant 3: SPL=64.9 dB(A)
The level difference between the variants 1 without/with lateral diffraction is
4.8 dB (10 log 3) in this example, since object geometry causes that the lateral
path length difference is equal to the path length difference of the direct path
across the house. In this case, for the non-transparent building the resulting
level with lateral diffraction is 4.8 dB larger than the level without lateral diffraction.
 03_Obstacles\Transparency\Calculation
Example 2 - with lateral
diffraction.xlsx
From the referenced MS-Excel file the calculation procedure can be studied
leading to these results applying the strategy described above.

The above statements apply to grid and facade points analogously.
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Chapter 3 - Obstacles
3.1.2 Acoustic Transparency (%)
In real situations, sources may be located within a partially transparent plant
or plant sub-structure. For example, valves within bundles of pipes represent
point sources which should - in this case - not be shielded by the surrounding
partially transparent building.
Sources inside of
transparent buildings
3
The option „Obstacles within Area Sources do not shield“ (on tab
„Industry“, see chapter 6.2.9.1) enables to enter point, line and area sources
inside the buildings perimeter. When enabled, the building causes not shielding to sources inside. For sources outside of the buildings perimeter, however, the screening effect is calculated using the specified configuration.
Examples
option "Obstacles within Area
Sources do not shield" active:
source inside the (semitransparent) building is not
screened.
option "Obstacles within Area
Sources do not shield" inactive:
source inside the building is
screened. In this case, the level is
also determined by a semi-transparent building due to the transmitted energy.
NOTE: With this setting of the
configuration option the
consistency check in CadnaA
indicates that there is a source
inside of a building.
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3
Transparency at
Reflections
3
Chapter 3 - Obstacles
3.1.2 Acoustic Transparency (%)
An acoustically transparent building causes the same amount of reflections as
does a non-transparent building. This means that the transparency effect applies to the diffracted energy, but not to the reflected one.
Example
Building with no transparency
Building with transparency 80%: Level in front of building
(source side) remains the same compared to no transparency
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Chapter 3 - Obstacles
3.1.3 Snap Point to Facade
3.1.3
Snap Point to Facade
This action on dialog Modify Objects or from the context menu enables to
relocate objects (e.g. point, line or area source or receiver point etc.) at a defined distance in front of building facades after they have been inserted.
3
The objects are attached to the facade with the distance defined in the edit
box Distance Points-Facade.
Distance PointsFacade
The operation is applied for all points with a distance smaller than the snap
radius.
Snap Radius
This could be necessary, e.g.
•
•
•
after objects have been inserted without activated Object Snap (see
chapter 9.3) but shall have a defined distance to the facade
in case objects have been placed inside a building, but shall be moved and
located at a defined distance from the building‘s facade or
when points have been imported from external sources
Point Source
Area Source vertical
House
Receiver
Initial situation: Building with a point source, a vertical area source and a receiver point. These
objects shall be dragged in front of the facade with a distance of 0,05 m.
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3
 Examples\03_Obstacles\SnapePointFacade.cna
3
Chapter 3 - Obstacles
3.1.3 Snap Point to Facade
In the shown example objects are located near a building. The receiver point
and the vertical area source shall be dragged to the building facade with a distance of 0,05 m.
•
Click with the right mouse key into the white area of the screen.
•
Select from the command Modify Objects and the action „Snap Point to
Facade“.
•
Mark the „vert. Area Source“ and the „Receiver“ as shown and confirm
with OK.
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Chapter 3 - Obstacles
3.1.3 Snap Point to Facade
3 19
The receiver point and the vertical area source are snapped to the building‘s
facade.
3
With activated options „Copy ID resp. Name“ of building the contents of
these fields is copied into the corresponding fields of the objects snapped.
Point Source
Area Source vertical
House
Receiver
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Chapter 3 - Obstacles
3.1.3 Snap Point to Facade
3
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Chapter 3 - Obstacles
3.1.4 Edit Facades
3.1.4
3 21
Edit Facades
The command Edit Facades on the context menu of the object „Building“
enables to edit in the graphics sound sources attached to building facades. In
addition, bitmap textures can be assigned to the facades and the roof
facilitating the data input and the generation of attractive 3D views.
After selecting the command, the dialog Edit Facades is displayed.
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Chapter 3 - Obstacles
3.1.4 Edit Facades
The dialog consists of a specific toolbar, a status bar and the following views
of the selected building:
3
•
top: front view of the all facades shown in-plane,
•
bottom left: top view,
•
bottom right: isometric view.
The scale of the front view can be changed using the toolbar (Zoom in/out,
Zoom to Limits). By contrast, the standard of top view and the isometry cannot be changed.
Local Coordinate System
u, v
Coordinated Display of
the Mouse Pointer
On the status bar, the local coordinates u (increasing to the right) and v
(increasing upwards) are displayed in a local coordinate system whose origin
(u, v)=(0, 0) is located in the lower left corner of the front view (i.e. the base
point of the building’s first polygon-point). When entering objects using the
mouse or the keyboard, the object coordinates refer to the local coordinate
system (u, v).

Note that, by contrast, the source coordinates x, y displayed on dialog
Geometry refer to the global coordinate system as already been used by
the 2D plan view.

The coordinates displayed on the dialogs Facade-Bitmap and RoofBitmap, however, always refer to the local coordinate system (u, v),
although the designations „X (m)“ and „Y (m)“ are displayed for software related reasons.
When the mouse pointer is moved in the front view, CadnaA shows the corresponding point on both, the top view and the isometric as well. This feature enables to figure out the current cursor position in the uv plane and
regarding the height. The input data of the entered objects can be edited by
double clicking onto the object’s border.
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Chapter 3 - Obstacles
3.1.4 Edit Facades
The following objects and features are available from this toolbar:
Select Edit Mode
Zoom in
Zoom out
Zoom to Limits
Point Source
Line Source
vertical Area Source
Facade-Bitmap *)
Receiver
Link to Roof-Bitmap *)
Copy to Clipboard
Print
Toolbar
3
Close Dialog
*) These features are available only with the CADNAA option BMP.
After having entered a new object the respective edit dialog is accessed in the
usual way (double-click on the object’s border while in edit mode, or click
with the right mouse button while in input mode).
For entered objects, a context menu with the following commands is
available (subsequent references refer to the manual „Introduction to
CadnaA“):
•
Edit (see chapter 12.1)
•
Delete (see chapter 11.1)
•
Duplicate (see chapter 11.3).
Furthermore, all options for graphical editing of objects can also be used
with the dialog Edit Facades (see chapter 4.3 in the manual „Introduction to
CadnaA“).
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Context Menu
24
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Chapter 3 - Obstacles
3.1.4 Edit Facades
Edit Objects
Point Source
3
Line Source
vertical Area Source
The same procedures as applied on the 2D-plan are used when defining the
geometry of point and line sources in CadnaA (see chapter 4.2.1 and 4.2.2 in
the manual „Introduction to CadnaA“). Each source dialog provides the edit
boxes as usual (see chapter 2.1.1).
When defining vertical surface sources, however, consider that also on the dialog Edit Facades just the upper edge is entered. The vertical extension of
vertical surface sources is - as before - entered as a positive distance from the
top („z-Extend“) to the bottom of the vertical area source.

A conclusive example showing the input of sources is described in
chapter 6.1.2 "Editing Facades" of the manual „Introduction to
CadnaA“.
Receiver
Receivers are entered as point objects as conventional. The distance of the receivers from the facade plane is defined on the dialog Object Snap (see
chapter 9.3).
Insert Bitmap

... for Facades
This symbol enables to insert facade bitmaps for texturing each part of the
building’s facade separately or, by using just a single bitmap which is
repeatedly used for texturing of all facade sections of the building. This feature facilitates the positioning of sound sources on each facade section and,
furthermore, offers to generate stunning 3D representations of buildings.
Proceed as follows:
The subsequent features require the option BMP!
•
Select the icon „Facade-Bitmap“ from the toolbar.
•
Drag an area inside a facade section and click with the right mouse button
on the border of the bitmap object. Alternatively, change to edit mode
and double-click with the left mouse button to open the dialog FacadeBitmap.
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Chapter 3 - Obstacles
3.1.4 Edit Facades
•
Edit the bitmap’s coordinates on the dialog Facade-Bitmap (see chapter
10.1.1 "Bitmap Size and Position"). When the real dimensions of the texture are known, enter it’s size starting from the lower left corner at (u, v)
= (0, 0).
The following additional options are available on the dialog Facade-Bitmap:
•
Repeat in X (i.e. in u-direction): With this option activated the bitmap
addressed to this facade section is repeated in u direction to the edge of
the facade section.
 Repeat on all facades: With this option activated the bitmap will also be
used on all other facade sections.
•
3 25
Repeat in Y (i.e. in v-direction): With this option activated the bitmap
addressed to this facade section is repeated in v direction to the edge of
the facade section.
The activation of the respective options „Repeat“ and „Repeat on all
facades“ is symbolized by arrows on the bitmap edges:
Symbols
Explanation
option „Repeat in X“ activated
option „Repeat on all facades“ (in x resp. u direction)
activated
option „Repeat in Y“ activated
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Chapter 3 - Obstacles
3.1.4 Edit Facades
The following options are just relevant for display of the facade bitmaps, and
even then only when the building‘s height is changed after having assigned
facades bitmaps. If the latter is not true, no changes are necessary. When
changing the building‘s height subsequently, it has to be decided - with
respect to the graphics - as to whether the facade bitmap remains at the
previous base point (option „Save Heights relative to Ground of Point 1“) or
whether it is moved upwards according to the building‘s new height (option
„Save Heights relative to Roof (z) of Point 1“):
3
•
Save Heights relative to Ground of Point 1: The vertical alignment of the facade
bitmap refers to the height of the building‘s first polygon point.
•
Save Heights relative to Roof (z) of Point 1: The vertical alignment of the
facade bitmap refers to the building height z (building‘s upper edge) at the
building‘s first polygon point.
Example
Default situation: All facades have facades bitmaps assigned. As long as no change of the
building‘s height occurs, it is irrelevant which
of the two options is selected for the each
facades bitmap.
When changing, however, the building‘s height
(here: height + 5 m) is has to be decided with
respect to the graphical representation
whether the assigned bitmap remains at the
height of building‘s first polygon point (right
facade with option „Save Heights relative to
Ground of Point 1“) or whether it is moved
upwards according to the building‘s new
height (left facade with option „Save Heights
relative to Roof (z) of Point 1“).
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Chapter 3 - Obstacles
3.1.4 Edit Facades

The information regarding the size and the file path of the bitmap/s is
stored in text variables of each building. Do not alter the text variables
BMPxx (for facades) and BMPROOF (for the roof, see below) as incorrect assignments may result.
This symbol enables to insert a roof bitmap for texturing the building’s roof.
Proceed as follows:
•
Select the symbol „Roof-Bitmap“ from the toolbar to open the dialog
Roof-Bitmap.
•
Edit the bitmap’s coordinates on the dialog Roof-Bitmap (see chapter
10.1.1 "Bitmap Size and Position"). When the real dimensions of the texture are known, enter it’s size starting from the lower left corner at (u, v)
= (0, 0).
The following options are available on the dialog Roof-Bitmap:
•
Texture Alignment: This option determines how the loaded texture gets
aligned on the roof’s surface.
 Gradient: With this option the texture starts at the highest point of roof
surface. This option is useful to apply when the roof ridge is modeled
using the object „Barrier“ with the option „Crowing: Roof Edge (3D)“
(see chapter 3.2.2 "Barrier with special crowning"). In this case, the
roof texture extends starting from the ridge line to the eaves.
 Point 1 - Point 2: With this option, the texture starts from the first polygon point of the building, extending from point 1 to point 2 of the
building’s polygon. Thus, the texture is arranged parallel to the first
polygon part of the building.

For non-rectangular shaped buildings the triangulation procedure
applied may generate additional triangles on the roof surface which do
not comply with the real roof shape. This effect is due to the
triangulation procedure and cannot be avoided with non-rectangular
shaped buildings.
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... for the Roof
28
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Chapter 3 - Obstacles
3.1.4 Edit Facades
Example 1
The texture of a glass facade will be assigned to facade section 1 using the
following coordinates:
Assigning Facade
Bitmaps
So, the facades bitmap represents a facade part with a width of 8 m and a
height of 6 m, starting in the lower left corner at coordinates (u, v) = (0, 0).
 Examples\03_Obsta-
After activation of all three options („Repeat in X“, „Repeat on all facades“
and „Repeat in Y“) and closing the dialog Facade-Bitmap the texture is displayed on the dialog Edit Facades as shown below.
3
cles\Edit Facades\example
1a.cna
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Chapter 3 - Obstacles
3.1.4 Edit Facades
3 29
Close the dialog Edit Facades and select the command 3D-Special from
the context menu of the building. The texture covers all sections of the
facade based on that single texture patch being 8 m wide and 6 m high.
3
3D-Special view with textures on all sections of the façade
In addition, a roof bitmap is assigned to the flat roof of the building.
The roof bitmap represents a 3 x 3 m wide section of the roof, starting at the
first house-point polygon.
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Assigning a Roof Bitmap
30
3
 Examples\03_Obstacles\Edit Facades\example
1b.cna
Chapter 3 - Obstacles
3.1.4 Edit Facades
Select the option „Point 1 - Point 2“ and close the dialogs. Select the command 3D-Special from the building’s context menu to display the roof covered by the selected texture.
3
3D-Special view with textured facades and flat roof

Regarding the use of textures to sloped roofs see chapter 3.1.5 "Defining a Roof Ridge".
Example 2
In this example, instead of using a single facades bitmap, different bitmaps
are assigned to each of the four facades. It should be noted that the
coordinates represent local coordinates u, v.
 Examples\03_Obstacles\Edit Facades\example
2.cna
•
Select from the file selector symbol in row „File“ the appropriate bitmap.
•
Enter on the dialog Facade-Bitmap the real dimensions of the facade section, starting in the lower left corner at coordinates (u, v) = (0, 0).
In this example, each facade sections is 21 m wide (in u-direction) and 9.5 m
high (in the v-direction). Thus, the following coordinates for the first section
are entered:
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Chapter 3 - Obstacles
3.1.4 Edit Facades
3 31
3
Subsequently, the texture of the first facade section is shown on the dialog
Edit Facades:
•
Now, enter the real dimensions of the second facade section.
Since all facade sections have a width of 21 m and a height of 9.5 m, the second section starts at the lower left corner u1=21 m and ends at u2 = 42 m.
So, the following coordinates for the second section are entered:
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Chapter 3 - Obstacles
3.1.4 Edit Facades
3
•
Continue with the remaining facade sections.
•
Close the dialog Edit Facades.
•
Press the key combination CTRL+3 to display the 3D-Special view
showing the textured facade.
3D view of a building with a textured facade
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge
3.1.5
3 33
Defining a Roof Ridge
The ridge of building roof can be modeled using the object „Barrier“ with
the crowning type „Roof Edge (3D)“ (see chapter 3.2.2 "Barrier with special
crowning").
Proceed as follows:
•
Enter a rectangular building of 10 m height.
•
Select the object „Barrier“ and draw a barrier in the middle and inside the
building’s polygon (or enter the coordinates on dialog Geometry of the
barrier).

With a barrier representing a roof ridge line and extending to the
outside of the building’s polygon, the outside part of the barrier will also
cause screening, but this part is not displayed on the 3D-Special view. In
the wire-frame view (menu Options|3D-View), however, it is displayed.
•
Open the dialog Barrier and select the crowning type „Roof Edge (3D)“.
•
Enter a height of 20 m via the button „Geometry“.
•
Close the dialog with OK.
Building with Barrier, type "Roof Edge (3D)", height 20 m
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Entering a Roof Ridge as a
Barrier
34
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge
•
Press the key combination CTRL+3 to display the 3D-Special view.
3
House with screening roof ridge
The roof area generated and displayed (in 3D-Special view) using the crowning type „Roof Edge (3D)“ is not a reflecting surface. Reflections at the object „Building“ result - as previously - from the vertical walls of the building
only, provided they are reflective and, at least, the first order of reflection is
selected (see chapter 6.2.8).
Assigning a roof bitmap
Now, a texture can be assigned to the roof surface (requires option BMP).
Proceed as follows:
•
Select the command Edit Facades from the context menu of the
building.
•
Select the symbol „Roof-Bitmap“
dialog Roof-Bitmap.
•
Edit on dialog Roof-Bitmap the bitmap’s coordinates (see chapter
10.1.1). When the real dimensions of the texture are known, enter those
values starting from the lower left corner at (u, v)= 0, 0).
•
On option „Texture Alignment“ select the option „Gradient“ in order to
align the texture starting from the highest point of the roof (i.e. the ridge).
•
Close the dialogs Roof-Bitmap and Edit Facades.
from the toolbar to open the
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge
•
Press the key combination CTRL+3 to display the 3D-Special view.
3
Building with pitched roof and roof texture
The roof texture is also used for the gable walls of the building. However, the
eave edge is not a screening edge, only shown in the 3D-Special view.
In the following an additional gable wall is entered. Starting with a building
having a roof edge already proceed as follows:
•
Activate while in edit mode the building’s polygon using the left mouse
button.
•
Hold down the CTRL key and click at the two locations of the building’s
polygon intersecting with the (imaginary) extension of the ridge line.
This will insert two additional polygon points.
•
Open the dialog Geometry of the building.
•
Select the option „Height at every Point“ and enter for the additional
points - for example - a height of 20 m.
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Defining gable walls
36
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge

Alternatively, you may of course enter all the coordinates x, y, z on the
dialogue Geometry directly.
3
Entering the height of the gable wall
•
Close the dialog with OK.
•
Press the key combination CTRL+3 to display the 3D-Special view.
Building with gable walls, roof ridge and roof texture
In this case, both, the roof ridge and the eaves edges cause screening.
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge
In addition to the pitched roof shown in the previous example more roof
shapes are possible, such as hipped, gambrel roof or tent shape.
Other Roof Shapes
3
Roof shapes (barriers are dotted lines):
top-left: mansard roof, -right: tent (with option „absolute Height at every Point“)
bottom-left: gable roof, -right: hip roof
3-Special view of several roof shapes
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Chapter 3 - Obstacles
3.1.5 Defining a Roof Ridge
3
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Chapter 3 - Obstacles
3.1.6 Generate Building
3.1.6
Generate Building
The command Generate Building is available from the context menu of the
area source. This command generates a building of a defined height with all
facades and the roof covered with area sources (by default at a distance of
0.05 m off the facade). All sources will receive the same emission data as
specified for the original area source where the vertical area source get
addressed a directivity index of K0=3 dB by default.
•
First, insert a area source in the shape of the horizontal projection of the
building.
•
Switch to the edit mode and double-click the area source. This opens the
edit dialog.
•
Activate the Sound Reduction option and enter an indoor level, either
directly or with reference to a spectrum. Enter all further parameters for
this source, and click OK to close the dialog.
•
Then click the area source with the right mouse button and select
Generate Building from the context menu.
3
In the Generate Building dialog, you can enter the parameters for the
height of the building and, if required, the height of the terrain at the base of
the building, and an absorption coefficient - either a single-number value or a
reference to a spectrum (see chapter 12.1 Local and Global Libraries).
•
Height of building relative (m): relative building height > 0 m
•
Height of ground absolute (m): After activation the absolute ground
height at the location of the building polygon can be specified. The
entered ground height effects the shape of the terrain depending on the
settings on the "DTM" tab.
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40
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Chapter 3 - Obstacles
3.1.6 Generate Building
•
3
Absorption: After activation the absorption coefficient can be entered
numerically or a spectrum can be selected via the file selector symbol
from local or global absorption library. After selection of an absorption
spectrum the spectrum's ID code is displayed on this box.
When all boxes are completed close the dialog by OK. CadnaA generates
•
a building with a specified height – 10 m in this example,
•
the appropriate number of vertical area sources whose parameters are
adopted from the first area source, at a distance of 0.05 m in front of the
facades,
•
a horizontal area source at 0.05 m above the roof and
•
(in case) a surrounding contour line (see chapter 4.1.1) with the absolute
height as entered.
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Chapter 3 - Obstacles
3.2 Barrier
3.2
3 41
Barrier
The calculation of the screening effect is based on the standard or guideline
selected for each noise type (see chapter 6.2.1). The available calculation options consequently depend on this selection as well. Information on the handling of barriers by a standard or guideline can be found in the following
chapters:
•
Industry: see chapter 2.1
•
Street: see chapter 2.4
•
Rail: see chapter 2.6
Reflections at the surfaces of a barrier are taken into account according to the
image source method if
1.
a order of reflection > 0 is selected (see chapter 6.2.8) and if
2.
the barrier is defined as reflecting by entering a reflection loss or,
alternatively, an absorption coefficient.
Depending on the selected standard or guideline additional conditions may
apply to generate a reflection at a barrier (or at any other possibly reflecting
obstacle), for example a minimum size/dimension in relation to the wavelength.
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Chapter 3 - Obstacles
3.2 Barrier
3
Dialog Options
Name, Memo-Window,
ID, ObjectTree
see chapter 4.4.2 in the manual "Introduction to CadnaA"
option „No Reflection“
This is the default setting. In this case, no reflected rays are generated, even
when a reflection order larger than zero is selected.
Reflection Loss/
Absorption Coeff. Alpha
Either the reflection loss or the absorption coefficient Alpha can be entered,
for each side separately. The specification „left“ or „right“ is based on the
viewing direction from first to last polygon point.
Via the respective file selector symbols
either a reflection type (according to RLS-90 /17/) or an absorption spectrum from the local or the global
(by SHIFT-clicking) library of absorptions can be selected.
Floating Barrier
see chapter 3.2.1
Crowning
see chapter 3.2.2
see also: chapter 3.2.3 "Barrier with transmission"
see also: chapter 3.8.1 "Automatically Optimize Noise Barriers"
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Chapter 3 - Obstacles
3.2.1 Floating Barrier
3.2.1
Floating Barrier
The floating barrier is a special object which is not described in the existing
standards or guidelines for calculating the sound propagation outdoors.
Originally, it has been designed to be used for modeling barriers on bridges
(see chapter 3.3).
3
Due to further development of CadnaA this application is obsolete
meanwhile because barriers on bridges or viaducts can be modeled more
comfortably by using the option „Self-Screening“ of roads (see chapter 2.4.1)
and railways (see chapter 2.6.1).
Nevertheless, the floating barrier can be used to model - for example elevated components in a plant (e.g. elevated horizontal or vertical tanks or
containers).
If this option is enabled, then the lower edge of the barrier is above the
ground level. Thus, this barrier is no longer attached to the ground.
Option "Floating Barrier"
In this input box - in addition to the geometry defined on the Geometry
dialog - the vertical extent from the top edge to the bottom edge of the
floating barrier is entered.
Z-Extent (m)
With a barrier height (upper edge) of 10 m relative and as a Z-extent of 3 m
the height of the barrier’s lower edge is 7 m above ground.
Example
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3
Properties of the
floating barrier
Chapter 3 - Obstacles
3.2.1 Floating Barrier
A floating barrier with the lower edge lifted from the ground has the
following properties:
1.
The screening effect is calculated - depending on the selected standard/
guideline - for each ray hitting the barrier surface, considering all three
propagation paths (diffraction across the top edge and laterally around
the barrier).
2.
Rays passing underneath the barrier’s lower edge are not attenuated (i.e.
free propagation).
3.
A diffraction effect around the bottom edge is not taken into account.

The diffraction algorithms found in the present standards and
guidelines normally just hold for a barrier’s upper edge standing
vertically on the ground. The diffraction around the lower edge cannot
be calculated using these algorithms, as the more complex interaction
with the ground is not included. Since a diffraction model is missing in
the standards, CadnaA does neither consider a diffraction effect.
4.
Reflections of rays hitting the barrier’s surface are calculated according
to the image source method.
3
Barrier on a Bridge
The procedure described below when entering a barrier on road or railway
bridges is superfluous by using the option „Self-Screening“ provided for the
object types „Road“ and „Railway“ (see chapter 2.4.1 and 2.6.1, for both in
section "Self-Screening").
When a barrier is located on a bridge, the height of the barrier section on the
bridge must be entered either by entering
•
the height of the top edge above the base plate of the bridge, and the
„Building Height“ button in the Geometry dialog must be activated that means 3 m in our example - and the same value must be entered for
the z dimension after „Floating Barrier“ has been activated, or
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Chapter 3 - Obstacles
3.2.1 Floating Barrier
•

the height of the top edge as an absolute value (13 m in the example. The
z dimension remains the same (3 m).
In both cases, further polygon points must be inserted for the barrier
where it intersects contour lines.
3
The barrier is calculated correctly in both cases.
10-m
contour line
Bridge
2 additional polygon points
Interpolate height of contour line
first point 10 m, last point 0 m
First point
Barrier on bridge
0-m contour line
Inserting a barrier on a bridge
•
In the two dialogs below enter the height of a reflecting barrier as 3 m
above bridge level.
3-m-high barrier on a bridge in the 3-D front view
Activate Floating Barrier in the edit dialog
CadnaA - Reference Manual
Specify the barrier height above the bridge by
selecting the „Roof“ option.
 Examples\03_Obstacles\Bridge.cna
46
3
Chapter 3 - Obstacles
3.2.1 Floating Barrier
The vertical grid shows the level distribution due to the reflection at the barrier (in the upper right half sphere) and the screening effect caused by the
barrier on the left side of the bridge.
3
Sound level distribution on a vertical grid for a road on a bridge with a floating barrier
see also:
chapter 2.4.1 "Common Input Data", section "Self-Screening"
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Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
3.2.2
Barrier with special crowning
Barriers having a special crowning can be edited and calculated in CadnaA,
depending on the calculation standard selected. In this case, select the desired
crowning from the list box „Crowning“ on dialog Barrier.
3
Option „Crowning“
•
normal: models a vertical screen with no crowning
•
Cantilever to the left/right: The designation „left“ or „right“ refer to a
viewing direction from first to last polygon point of the barrier. Enter the
horizontal and vertical extent of the cantilever (in m). The location of the
cantilevered part is displayed in the graphics by a dashed line.

•
At the cantilevered surface is no reflection is calculated. So, the
cantilever is assumed to be fully absorbing. With a single barrier, the
level calculated with sources below and outside the cantilevered part is
valid.
T-shaped (only available with option MITHRA or NMPB08): Enter the
dimensions (in meters) of the T part perpendicular to the surface
(permissible value range 0.85 to 1.50 m).
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Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
•

3
•
Button "Geometry"
Cylindric (only available option MITHRA or NMPB08): Enter the diameter (in m) of the cylinder (permissible value range 0.60 to 1.00 m).
In CadnaA, the Mithra barrier crownings are considered only:
- with NMPB 08 (Industry, Road, Fer), whether Mithra option is on or
off (see chapter 6.2.2)
- with Mithra option activated (and hence Angle Scanning, see chapter
6.2.2): for every standard being selected.
Roof Edge (3D): When barriers are modeled inside buildings this option
caused the building polygon to be generated by triangulation using the
barrier’s and the building’s height. In this case, just the roof ridge modeled
by the barrier causes screening, but not the triangulated roof edges (see
chapter 3.1.5).
Via the button „Geometry“ the barrier’s height is specified (see chapter 4.2).
Additional
Information
Crowning "Normal"
The type „(normal)“ is applicable to all kinds of calculation methods. The
polygon describing the barrier is considered in the calculation of the screening effect. The diffraction algorithm according to calculation method selected
is applied.
Crowning with Cantilever
Whether the option „Cantilever top the left/right“ is applicable depends on
the calculation method selected. The following chapters contain related
information:
•
•
•
Guidelines for Input
Industry: see chapter 6.2.9
Road: see chapter 6.2.10
Railway: see chapter 6.2.11
Enter a value for the horizontal and vertical part of the cantilever. The height
of the barrier displayed on the dialog Geometry is the height of the
diffracting edge at vertical, plane barriers.
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Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
3 49
By selecting "left" or "right" the cantilever directs into this direction when
looking from the first to the last polygon point. The cantilevered part is
displayed using a dashed line.
As an example, the barrier height is 6 m (on dialog Geometry), and the
cantilever horizontal and vertical 1 m results in the following figure.
Barrier with cantilever displayed in 3D front view
Barrier with cantilever in 3D-Special view
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Crowning „T-shaped“
Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
Barriers with crowning attribute „T-shaped“ are valid for all calculation
methods with "Mithra-compatibility" activated.
The value for the width has to be between 0.85 and 1.5 m. The T-shaped
crowning is created symmetrically on top of the barrier, with half the width
on either side (is shown in 3D-Special).
3
Crowning „Cylindric“
Barriers with crowing „Cylindric“ are valid for all calculation methods with
"Mithra-compatibility" checked.
After entering a value for the diameter between 0.60 and 1.00 m a cylindric
crowning is created with the upper centre line of the barrier (is shown in 3DSpecial).
Crowning „Roof Edge
(3D)"
The triangulation of the roof surface inside a building’s polygon occurs just
for barriers having the option „Roof Edge (3D)“ selected. This enables to
model real roof structures, also for display in the 3D-Special view providing a
screening effect (see chapter 3.1.5 "Defining a Roof Ridge").
When modeling a roof ridge, however, this option does not generate gable
walls raising up to the roof ridge. In order to enter a gable wall up to ridge
height, additional points making up the building polygon are required (at the
intersections between roof and exterior wall). In this case, use the option
„Height at every Point“ from dialog Geometry of the building (see chapter
3.1.5 "Defining a Roof Ridge").
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Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
With regard to the practical application of barriers with cantilever the
following situations apply:
•
source below the cantilever,
•
source outside of the cantilever.
In order to calculate these situations correctly, the shortest ray path must be
found starting from the source around the cantilever’s edge to the receiver
point. The method applied will retrieve the shortest path difference for a single barrier in the entire space. Regardless of the receiver point’s location, one
or two diffracting edges are taken into account. As mentioned already, the
sloping surface of the cantilever is considered to be full absorbing. This feature enables to model porches or galleries alongside of roads with their lower
surfaces being absorbing.
Example: point source and barrier with cantilever
Vertical Grid: point source directly below the cantilever’s edge
Vertical Grid: point source below the cantilever (Dz without limit)
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Application Notes for
Cantilever
3
Source below the
cantilever
52
3
Source outside the
cantilever
Chapter 3 - Obstacles
3.2.2 Barrier with special crowning
The same procedure is applied with sources below the cantilevered part. The
levels are valid for single barriers within the entire space.
3
Vertical Grid: point source outside of the cantilever
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Chapter 3 - Obstacles
3.2.3 Barrier with transmission
3.2.3
Barrier with transmission
All calculation standards for the sound propagation outdoors treat the
screening at obstacles (e.g. at barriers) not accounting for sound transmission
through the obstacle. With this approach it is implicitly assumed that the
screening effect (possibly including lateral diffraction) is the dominating effect when calculating the sound propagation.
In order to ensure that this requirement is met, several calculation standards
specify a lower limit of the surface mass or a minimum (weighted) sound reduction index (transmission loss or STC) of the screening obstacle. For example, ISO 9613-2, section 7.4, states /8/:
3
Validity of diffraction
equations
„An object shall be taken into account as a screening obstacle (...) if it meets
the following requirements:
 the surface density is at least 10 kg/m²;
 the object has a closed surface without large cracks or gaps ...
Each object that fulfills these requirements shall be represented by a barrier
with vertical edges. ...“
Considering the transmitted energy through the barrier requires that the
weighted sound reduction index Rw (or STC) or the sound reduction
spectrum (transmission loss spectrum) of the barrier is available.
Proceed as follows to model a barrier with a finite transmission:
•
Activate the object snap on dialog Options|Object Snap with a
„Distance Points-Facade“ of 0.05 m (default value).
•
Place a receiver in the middle of the barrier on the sound source side.
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Considering a finite
sound transmission
54
3
Chapter 3 - Obstacles
3.2.3 Barrier with transmission
•
3

When the barrier has reflective properties, make sure that in the
configurations, „Reflection“ tab, a „Min. Distance Receiver-Reflector“ of
1.00 m and a „Min. Distance Source - Reflector“ of 0.10 m is specified
(see chapter 6.2.8).
In conjunction with the setting for the ObjectSnap, these standard configuration settings ensure that the level calculated at the receivers does
not include any reflection component (thus, being the free field level)
and that the sound power radiated by the vertical area source does not
include any reflection component from ray-tracing (i.e. the reflection is
considered by the directivity index K0=3 dB on the source dialog, see
chapter 2.1.1, section "K0 without Ground").
•
Calculate the receiver level, either as an A-weighted single value or as a
spectrum.
•
Enter on the far side of the barrier (as seen from the source) a vertical
area source (see chapter 2.1). Apply the command Parallel Object from
the barrier‘s context menu (entering a distance of 0.05 m, a height difference of 0 m, and a Z-extend of 8 m corresponding to the barrier‘s height).
The directivity index „K0 w/o ground“ of 3 dB is maintained as the
source radiates into half sphere (i.e. not considering the ground reflection
here).
•
The emission of the vertical area source results from the receiver level on
the source side and from the sound reduction index (or STC) of the barrier:
 when the receiver level on the source-side is an A-weighted level:
SPLi = SPLsource side + 4 dB
 when the receiver level on the source-side is a spectrum:
SPLi (f) = SPLsource side (f) + 6 dB (in each frequency band).

This numerical approach for the calculation of the interior levels compensates for the procedure used in the VDI guideline 2571 /37/ (see
chapter 2.1.1, section "Transmission Loss").
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Chapter 3 - Obstacles
3.2.3 Barrier with transmission
•
Activate the option „TransLoss“ on the dialog vert. Area Source and
enter into the box „Interior Level“ the value SPLi as determined or establish a reference to a sound level spectrum (after having entered spectrum
via the menu Tables|Libraries (local)|Sound Levels).
•
Enter the weighted sound reduction index or establish a reference to a
transmission loss spectrum (after having entered spectrum via the menu
Tables|Libraries (local)|Sound Reduction Indeces).
•
Restart the calculation.
Now, the resulting levels contain the transmitted energy fraction.

Note that the procedure described above is an approximation making
use of some assumptions. For example, this approach assumes a
uniform sound distribution on the source-side of the barrier. Moreover,
it is no taken into account that the sound reduction (transmission loss)
may depend on the angle of the inciding sound.
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Example 1: Procedure
with A-weighted levels
Chapter 3 - Obstacles
3.2.3 Barrier with transmission
The example file shows the following arrangement of objects (here for variant 2 „with Transmission“)
3
... with the following input data for the vertical area source when calculating
using weighted data (A-weighted interior level and sound reduction index, Rw
(STC) = 10 dB):
 Examples\03_Obstacles\Barrier with Transmission\example 1 barrier transmission using
A-weighted level.cna
Toggle variants „without transmission“ and „with transmission“ in order to
assess the influence of the transmission in this example.

In this example, the non-spectral ground attenuation according to ISO
9613-2, section 7.3.2, is used /8/.
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Chapter 3 - Obstacles
3.2.3 Barrier with transmission
The sample file shows the arrangement of objects (again for variant 2 „with
Transmission“)
Example 2: Procedure
using spectra
3
... with the following input data for the vertical area source for invoice with
spectral data (spectral indoor level and spectral transmission loss):
Toggle variants „without transmission“ and „with transmission“ in order to
assess the influence of the transmission in this example.

In this example, the spectral ground attenuation according to ISO 96132, section 7.3.1, is used /8/.
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 Examples\03_Obstacles\Barrier with Transmission\example 2 barrier transmission using
spectrum.cna
58
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Chapter 3 - Obstacles
3.2.3 Barrier with transmission
3
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Chapter 3 - Obstacles
3.2.4 Barrier staggered in height
3.2.4
Barrier staggered in height
The calculation procedures for sound propagation outdoors do not cover
barriers with sections staggered in height and having different absorptive
properties. Screens (and all other types of obstacles) always have a uniform
reflection loss or absorption coefficient on each barrier side.
3
Due to the practical relevance of such a barrier design, the recommended
procedure in CadnaA is described below. A barriers with sections staggered
in height is modeled by two distinct barriers, the base line of which are close
to each other (e.g., at a distance of 0.10 m).
To this end, the barrier having a higher absorption coefficient (larger
reflection loss) is facing away from the source, while the barrier having a
smaller absorption coefficient (smaller reflection loss) is placed on the
source-facing side.
Example 1: barrier with an absorbing lower part and a reflective upper part
(modeled from two barriers, vertical cross section):
Examples
 Examples\03_Obstacles\Barrier - staggered\example 1 - lower
part absorb - upper part
reflect.cna

In the 3D-Special view the sound rays are represented as line sources
having no emission (resulting from converting the rays being auxiliary
polygons).
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3
 Examples\03_Obstacles\Barrier - staggered\example 2 - lower
part reflect - upper part
absorb.cna
Chapter 3 - Obstacles
3.2.4 Barrier staggered in height
Example 2: barrier with a reflective lower part and an absorbing upper part
(modeled from two barriers, vertical cross section):
3

Limitations
In the same way, barriers can be modeled consisting of several sections
having different absorption.
The reflected ray paths, generated based on the heights of the source and the
reflecting obstacles, hit either the absorbing or the reflecting region of the
staggered barrier. Consequently, in a specific geometrical situation, the noise
increasing effect may not occur and at each receiver point.
In this example (vertical cross section), there are two receivers on a facade at
which reflections of 1st order occur at a barrier with sections staggered in
height. The level at the upper receiver is includes the reflection loss of the
rear, absorbing barrier, while the level at the lower receiver includes the reflection loss of the reflecting barrier in front.
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Chapter 3 - Obstacles
3.3 Bridge
3.3
3 61
Bridge
The object "bridge" represents a horizontal plate causing diffraction from
sources located below or above. This object was the only way in former
releases of CadnaA to model a screening plate lifted above the ground.
Due to the option „Self-Screening“ of the objects „Road“ and „Railway“ the
object „Bridge“ became dispensable for modeling of bridge plates (see section „Self-screening“ of roads, chapter 2.4, and of railways, chapter 2.6).
The object „Bridge“ has the following properties:
•
The bridge is a horizontal plate being a closed polygon. All sound rays not
intersecting the bridge remain unaffected.
•
When a sound ray by a source lies above the bridge plate intersects the
plate the diffraction is calculated for receiver points not directly below the
bridge’s plate.
•
For sound rays from sources lying below the bridge intersecting the plate
to receiver points above the bridge the diffraction is calculated due to the
bridge’s edge.
•
Diffraction into the space below the bridge is not considered. Therefore,
resulting levels below the bridge are irrelevant!
•
The bridge plate is assumed to have a plane surface being parallel to the
reference plane regardless of the terrain’s contour.
•
The height of the bridge is always taken from the first polygon point (dialog Bridge|Geometry). Heights entered for further polygon points are
not relevant.
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3
Chapter 3 - Obstacles
3.3 Bridge
•
The bridge plate is considered as if it were a building’s roof. When the
bridge’s height attribute is set to „Roof“ (dialog Bridge|Geometry) the
height above the bridge’s level is entered.
•
On the vertical grid or on the cross section the bridge plate is not displayed.
The sound diffracted downwards from roads or railway lines on top of the
bridge are calculated correctly considering the diffraction around the bridge’s
edges. Rays passing below the bridge causing an immission on the opposite
side are considered automatically.
Due to the „floating barrier“-option even barriers on a bridge can be modeled (see chapter 3.2.1 "Floating Barrier").
 Examples
see also directory “Examples\03_Obstacles\Bridge“
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Chapter 3 - Obstacles
3.4 Ground Absorption Areas
3.4
Ground Absorption Areas
The object „ground absorption“ causes an attenuation
•
if the selected standard or guideline (see chapter 6.2.1 "Country Tab")
applies the ground factor G (originally used by VDI 2714 /38/ and ISO
9613-2 /8/),
•
or a different parameter is used to specify the dampening effect of the
ground which can be transferred into an appropriate value of the ground
factor G.
•
When a standard or guideline includes several, different ground
attenuation models a further selection on the relevant configuration tab
for the a specific source type may be required (e.g. see chapter 6.2.9.1
"ISO 9613").
3
For more information regarding the guideline-specific procedures for calculating ground attenuation see chapter 6.2.9 "Industry Tab", chapter 6.2.10
"Road Tab", and chapter 6.2.11 "Railroad Tab".
In case the selected standard or guideline applies a generalized ground
attenuation model - i.e. the ground attenuation does not depend on the local
ground properties, but is just determined from the ray‘s geometry - the object
„ground absorption“ does not cause any damping effect.
Dialog Options
see chapter 4.4.2 in the manual "Introduction to CadnaA"
Name, Memo-Window,
ID, ObjectTree
value of the ground factor G (accord. to ISO 9613-2), default value G=0
Ground Absorption G
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Object‘s Geometry
Chapter 3 - Obstacles
3.4 Ground Absorption Areas
The object is entered as a closed polygon with the height specified - if any on the dialog Polygon: Geometry is not relevant.
With multiple ground absorption areas overlapping each other, the area on
top represents the overlap region. This is equal to a lower position of the respective absorption area in the table Ground Absorption (see Tables|
Obstacles menu).
3
Special Case: Road & Rail
In conjunction with the self-screening option for the objects „Road“ and
„Railway“ an additional width can be entered specifying the ground
absorptive properties within the road or railway track area (see chapter 2.4.1
and 2.6.1, both section "Only for Ground Absorption, no Screening").
„Ground Absorption“
tab
see Calculation|Configuration menu, „Ground Absorption“ tab (see chapter 6.2.7)
Default Ground
Absorption
This value specifies the ground factor G for areas not covered by the object
„Ground Absorption“ (default value 1, range 0<=G<=1).
Option „Use Map of
Ground Absorption“
This option enables - in case numerous ground absorption areas - to reduce
the calculation time by generating a map of ground absorption areas.
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Chapter 3 - Obstacles
3.5 Built-Up Areas and Foliage
3.5
Built-Up Areas and Foliage
Built-up areas are defined by a closed polygon and by its height (on dialog
Geometry). The resulting attenuation due to built-up areas depends on the
guideline selected for the respective type of source.
Built-Up Areas
3
With calculation according to VDI 2714 or ISO 9613-2 the attenuation due
to built-up areas is taken into account for areas as defined. When calculating
traffic noise with the setting „strictly according to RLS-90“ or „strictly
according to Schall03“, however, no attenuation occurs with built-up areas
(tabs Road“ and „Railroad“ on dialog Calculation|Configuration).
Dialog Built-Up Area
According to VDI-guideline 2714, section 6.4.2, the attenuation by built-up
areas DG for single sources and for propagation through scattered buildings
(i.e. no extending building facades):
DG = (m * B * sG - DBM) dB  0 dB
where
 m: average reciprocal length of edges in 1/m
 B: area coverage (of buildings) in %
 sG: length of sound path through the built-up area in m (for this reason
the height of the object „Built-Up Area“ is relevant)
 DBM: attenuation due ground & meteorology in dB
With single buildings the average reciprocal length of edges is 0.1 m-1 at
maximum. With scattered halls smaller values for m apply.
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Calculation according to
VDI 2714
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Chapter 3 - Obstacles
3.5 Built-Up Areas and Foliage
The length of sound ray sG through the built-up area is evaluated for a curve
radius of 5000 m from source to receiver. Enter the average height of
buildings with the area in dialog Built-Up Area|Geometry.
According to VDI-guideline 2714 the sum DBM+DD+DG is limited to a
maximum value of 15 dB (DD: attenuation due to foliage).
3
The application of the object Built-Up Area is useful where the geometry of
individual objects is not available. Otherwise, the object Building should be
used.
Calculation according to
ISO 9613-2
According to ISO 9613-2, annex A.3, the attenuation due to housing AHous,1
results from:
AHous,1 = 0.1 * B * dB dB
where: - B: area coverage in %
- dB: length of sound path through the built-up area in m
The attenuation due to housing AHous,1 is limited to 10 dB according to ISO
9613-2. The sum of attenuations Agr+Afol+Ahous, however, is not limited to
15 dB - compared with VDI 2714. Using a text block with the name
OLD_OPT_CALC this limitation can be engaged (text to be entered:
iso_asum_15db_x125=1).

The contribution of AHous,2 according to ISO 9613-2, annex A.3, is not
considered by CadnaA.
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Chapter 3 - Obstacles
3.5 Built-Up Areas and Foliage
Dense woods („foliage“) are defined by a closed polygon and by its height
(on dialog Geometry). The resulting attenuation due to foliage depends on
the guideline selected. In the following, the procedures according to VDI
2714, ISO 9613-2, and Schall 03 (1990) are explained.
Foliage
According to VDI-guideline 2714, section 6.4.2, the attenuation due to
foliage DD calculates from:
Calculation according to
VDI 2714
for A-weighted levels:
DD  0.05 dB / m  sD
for spectra:
1 / 3§

 f  
DD  0.006
  dB / m  s D
 Hz  

with sD: length of sound path through the foliage in m.
The length of sound ray sD through the foliage is evaluated for a curve radius
of 5000 m from source to receiver. Enter the average height of buildings with
the area in dialog Foliage|Geometry. The resulting attenuation just holds
for permanent (leaves!) and dense woods (i.e. with dense undergrowth).
According to VDI-guideline 2714 the sum DBM+DD+DG is limited to a
maximum value of 15 dB (DG: attenuation by built-up areas).
According to ISO 9613-2, annex A.2, attenuation due to foliage calculates
from:
Afol = Df * df
with df: length of sound path through the foliage in m.
with the attenuation Df as shown in the next table:
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Calculation according to
ISO 9613-2
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3
Chapter 3 - Obstacles
3.5 Built-Up Areas and Foliage
path length
df (m)
octave band
center frequency (Hz)
63
125
250
500
1k
2k
4k
8k
10 <= df <=
20
attenuation
(dB)
0
0
1
1
1
1
2
3
20 <= df <=
200
attenuation
(dB/m)
0,02
0,03
0,04
0,05
0,06
0,08
0,09
0,12

Calculation according to
Schall03 (1990)
The attenuation by built-up areas DG is not limited by ISO 9613-2.
The procedure corresponds with the calculation in guideline VDI 2714 for
A-weighted levels.
When performing road noise calculation with setting „strictly according to
RLS-90“ no attenuation due to foliage is considered.
Calculation according to
Schall03 (2014)
The attenuation due to foliage is not considered (see section 6.1 in /26/).
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Chapter 3 - Obstacles
3.6 Cylinder
3.6
Cylinder
The cylinder is screening object raising vertically from the ground. The
cylinder may have a reflective properties. When entering a cylinder using the
mouse, first click to it’s center point and then define the radius.
3
Line source
Immission
point
Source
Reflecting cylilnder
Screening at a circular cylinder
Reflections at a circular cylinder
By default, cylinders - as with the object „Building“ (see chapter 3.1) - are
modeled without a roof plate, although this is displayed in the 3D-Special
view (see chapter 9.14). For sources above roof level the ground attenuation
results from the source height above ground and not above roof (as the roof
is not a reflecting surface).
see chapter 3.1, section "Internal Sources"

When modeling the radiation by cylindrical buildings it is recommend
to convert the cylinder first into the object „Building“ (see chapter
11.13, manual „Introduction to CadnaA“) and then to apply the command/ action „Parallel Object“ (see chapter 11.19, manual „Introduction to CadnaA“) is a vertical circumferential surface source.
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Chapter 3 - Obstacles
3.6 Cylinder
Dialog Options
3
Dialog Cylinder
BEZ, Memo-Window, ID,
ObjectTree
see chapter 4.4.2 in the manual "Introduction to CadnaA"
Reflection Loss/
Absorption Coeff. Alpha
By default, cylinders are not reflecting sound (option „No Reflection“). Selecting one of the options „Reflection Loss“ or „Absorption Coefficient
Alpha“ enables to specify via the respective file selector symbol
either a
reflection type (according to RLS-90 /17/) or to address an absorption spectrum from the local or the global (by SHIFT-clicking) library of absorptions.
In this case, reflections from the cylinder’s surface are taken into account up
to the first order of reflection applying the image source method, provided
that on tab „Reflection“ (see chapter 6.2.8) in the configuration of calculation
at least the first order of reflection is selected.
Button "Geometry"
Via the button „Geometry“ the cylinder’s height is specified (see chapter 4.2).
 Examples\03_Obstacles\Cylinder - abs Height
- Input of Ground
Height.cna

Sources in Cylinders
do not shield
The option „Sources in Buildings/Cylinders do not shield“ is available for
industrial sources (see chapter 6.2.9 "Industry Tab").
When entering the absolute height and the ground height using a value
above the actual ground level the same restrictions specified in chapter
3.1 "Building", section "Button "Geometry"" hold for cylinders as well.
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3.7
3 71
3D-Reflector
The object „3D-Reflector“ is a special object not described by any standard
or guideline with respect to its properties and its screening effect.
3
Inclined, floating 3D reflector in the 3D view
The 3D-reflector models a freely orientated, arbitrarily shaped closed and
plane polygon area, where the shortest path difference between source and
receiver determines the screening effect. In addition, lateral diffraction and
reflections up to the 1st order are taken into account. Distinct edges of 3Dreflector can be excluded from the calculation of lateral diffraction (see below
„Exclude Edges“). This prevents for diffracting around the selected edge, for
example, at geometrically adjacent obstacles.
The reflector surface must form a flat surface. When polygon points are not
in a plane, a plane surface is generated by quadratic averaging. In these cases,
the reflector surface is still displayed as being defined originally by the suer
(for example, for display on the 3D special view).
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Normative
References
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3.7 3D-Reflector
The 3D-reflector as a special object is just compatible with such standards
and guidelines, using a diffraction model evaluating the path difference based
on path geometry only. Therefore, the 3D-reflector shows no effect with
standards and guidelines (i.e. no screening) which are based on a diffraction
model using, for example, an additional height h or which exclude certain
obstacles in the ray path from the diffraction calculation (e.g. „the most efficient barrier“ etc.).
By default, the 3D-reflector is, therefore, just compatible with the following
standards and guidelines whose diffraction models comply with the above
conditions and where the screening effect by multiple obstacles in the ray
path is evaluated by applying so-called „rubber-band-method“:
•
ISO 9613-2
•
RLS-90
•
Schall 03 (1990) and Schall 03 (2014)
For more information on guidelines-specific procedures for assessing diffraction and on the effectiveness of the effectiveness of 3D-reflector see chapter
6.2.9 "Industry Tab", chapter 6.2.10 "Road Tab", and chapter 6.2.11 "Railroad Tab".
Configuration of
Calculation
The configuration settings on tabs „Industry“, „Road“ and „Railway“ are also
relevant when calculating diffraction of the 3D reflector. Please note in special:
•
For the German procedures „RLS-90“ (road) and „Schall 03“ (railway)
the exclusion of the lateral diffraction and the suppression of the ground
attenuation is strictly regulated (option „Strictly acc. to ...“).
•
For industrial sources, the lateral diffraction can be accounted for or not
and the screen coefficients may be modified if necessary (see chapter
6.2.9 "Industry Tab").
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Dialog Options
3
see chapter 4.4.2 in the manual "Introduction to CadnaA"
Name, Memo-Window,
ID, ObjectTree
By default, the 3D-reflector does not reflect sound (option „No Reflection“).
Selecting one of the options „Reflection Loss“ or „Absorption Coefficient
Reflection Loss/
Absorption Coeff. Alpha
Alpha“ enables to specify via the respective selector symbol
either a reflection type (according to RLS-90 /17/) or to address an absorption spectrum from the local or the global (by SHIFT-clicking) library of absorptions.
In this case, reflections from the reflector’s surface are taken into account applying the image source method, provided that on tab „Reflection“ (see chapter 6.2.8) in the configuration of calculation at least the first order of
reflection is selected.
Regard the definition of „left“ and „right“ reflector side „right-hand-rule“
applies: Suppose the right hand being curved along the outer edge of the
polygon, the fingers pointing from the first to last point, the stretched thumb
points into normal direction of the „right“ side.
Left/Right Side
On the dialog Exclude Edges (see below) the reflector‘s edges can be
marked not to be taken into account in the calculation of diffraction. Up to
32 edges of the 3D-reflector can be excluded. A 3D-reflector consisting of
more than 32 edges, those further edges cannot be excluded.
Button „Exclude Edges“
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Dialog Exclude Edges
3
List „Excluded Edges“
Click once on the edge's designation (e.g. E01) to exclude this edge from the
next calculation of diffraction.
Graphic Display
An edge having been excluded is displayed in the graphics without a facade
point symbol (octagon) attached. A further click on the designation includes
the edge again into the calculation of diffraction.
On the lower graphics, the actually selected edge is marked by a thick black
line. Alternatively, a double-click onto an edge in the graphics excludes/includes this edge.
Zooming in the Graphics
After a mouse click into the graphics the sketch can be zoomed in/out.
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In conjunction with the application of the 3D-reflector, several questions
may arise which are answered in the following.
Additional Information
The majority of calculation standards or guidelines just allow for barriers
standing vertically on the reference plane, with the upper edge being straight
and possibly inclined. The 3D-reflector offers a solution for special cases
where one or more of the following characteristics have to be considered:
Restriction to specific
Standards/Guidelines
•
reflection from irregularly limited vertical surfaces,
•
reflection from surfaces which are neither horizontal, nor vertical,
•
diffraction at arbitrarily edges, including diffraction upwards.
This solution represents a „stand-alone“ solution, since the calculation of the
reflection and the diffraction at the 3D-reflector occurs without considering
the (potential) interactions with other screening/diffracting objects. In order
to calculate the screening effect, only those standards and guidelines are suitable which are just using the geometrical path length difference, not using an
additional height (e.g. in order to correct for a parabolic ray path across the
top edge). In addition, no standards or guidelines are appropriate, based on
the so-called „most effective“ barrier or similar criteria. These methods are
not suitable in the case of 3D-reflector since the edge determining the final
screening effect can be oriented freely in space where above corrections do
not apply.
The equations used by standards to calculate the screening effect just refer to
plane barriers. Thus, it requires to enforce a plane barrier by the software if
necessary. This is done in the first calculation step (see section "Software-internal procedures" below).
Restriction to plane
barriers
Since the 3D-reflector is freely orientable in space, reflecting rays from the
3D-reflector‘s surface (for 1st order of reflection) may point to the ground.
Restriction to 1st order
reflections
Further, since all algorithms used for prediction of the sound propagation
outdoors do not use image source to consider ground reflection (but based
on source/receiver height, as well as their distance), this ground reflection
could not be included into the image source method without violating the ba-
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3.7 3D-Reflector
sic principles of sound propagation models. Therefore, reflections higher
than the 1st order cannot not be allowed.
3
Note, furthermore, that reflections - as with all other types of reflective
objects - are included in the calculation only when the respective ray paths
can be constructed geometrically (with angle of incidence = angle of
reflection). In case a reflection path cannot be constructed, the reflection
from this object can, nevertheless, be relevant acoustically, but cannot be
included in the calculation because of limitations of the ray tracing approach.
This illustrates that the construction of reflecting paths using ray tracing just
serves as a reasonable approximation.
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As part of the calculation the following software-internal procedural steps are
carried out:
•
•
The input of a 3D-reflector occurs using a polygon having any shape and
with an individual height at each polygon point. In this step it is checked
whether the entered polygon creates a plane surface (see „user defined 3d
polygon“ in the figure below). If this is not the case, the new z-coordinates are determined causing all polygon points to be in-plane and the
sum of the squared height differences dH are a minimum (see „plane 3D
polygon used for calculations“). The entered object coordinates, however,
are kept for display.
The image source method is applied to calculate of reflections the reflection point, if any. The reflection (specified by the absorption coefficient
or the reflection loss) is taking into account only when the reflection
point lays inside of the polygon (causing a separate reflected ray).
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3.7 3D-Reflector
•
3
In the calculation of diffraction it is assumed that three diffracted rays
contribute to the receiver level: across the direct path and two lateral
paths. For this purpose, the following strategy is applied:
 If source and receiver are located at different sides of the 3D-reflector
(i.e. the line between source and receiver intersects with the 3D-reflector), the intersection point S inside the polygon is calculated (see figure
below).
 The ray path having the smallest path length difference and thus
provides the highest contribution is evaluated. This is achieved by calculating the distances of all polygon edges from the intersection point.
The shortest distance determines the edge with the largest
contribution. Using the length (Q-S1*-P) - (Q-P) the attenuation for
this path calculated (see figure below).
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3.7 3D-Reflector
•
•
The calculation of lateral screening is carried out as follows: The two
points S2* and S3* that are used for the calculation of lateral diffraction
are found by calculating the intersection of the straight line through S
(laying in the reflector‘s plane) having a right angle towards S-S1* (see figure below).
The contributions of these two lateral diffraction rays and of the
diffracted direct path results the final screening effect.
In the figure below all three diffracted ray paths are shown in blue.
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Joints to other obstacles
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3.7 3D-Reflector
Joints between normative objects (e.g. between buildings and barriers) are
recognized by CadnaA automatically, thus requiring no intervention by the
user.
With the 3D-reflector, however, interactions with other screening objects are
not seen and not considered. For example, is not checked and not
automatically detected whether a 3D-reflector is situated close to any other
obstacle (e.g. a neighboring building). In these situations, the diffraction
around the edge in question is not prevented for automatically (see also section "Screening effect" further in this chapter).
However, the user may exclude one or more edges of 3D-reflector from the
calculation of diffraction.
Please note again that the calculation of reflections and of the screening
effect of the object „3D-reflector“ is not treated in any standard or
guideline. The solution provided in CadnaA may be understood as a
plausible extension of ISO 9613-2, RLS-90 and Schall03 (1990) or
Schall03 (2014). Even with these standards or guidelines it cannot be
assured that always reasonable screening effects result in arbitrary object combinations.
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The following section describes what screening effect results using a single
3D-reflector or in combination with other screening objects.
Screening effect
With just a single 3D-reflector in the ray path, the strategy as described in the
section "Software-internal procedures" is applied (see above).
Single 3D-reflector in ray
path
With several 3D-reflectors in the ray path, the screening effect by each 3Dreflector is calculated individually, using the strategy as described in section
"Software-internal procedures". Afterwards the final screening effect equals
to the highest screening of all 3D reflectors in the path. This value is used to
calculate the final barrier attenuation Abar..
Several 3D-reflectors in
ray path
In order to understand this approach, the following hints are useful to
consider: The strategy (based on the shortest path difference of the direct
path) would, being applied consistently for multiple 3D-reflectors in path,
cause a more or less meandering path of the diffracted ray around all
obstacles. Since every 3D-reflector may have an arbitrary shape and freely
orientated, the diffracted ray would not travel always across the upper edges
of obstacles, but could travel once across the top edge, then across the
bottom edge or around the left or right edge. It will be appreciated that this
approach would lead to an unrealistically large path difference and thus an
heavily over-estimated screening effects. In the end, this effect must be
controlled and suppressed by the algorithm used.
When there are one or more 3D-reflectors and other „conventional“
obstacles in path (e.g. buildings, barriers, embankments etc.), first the
combined screening effect Abar,conv of these obstacles using the „rubberband-method“ is determined. Subsequently, for each 3D-reflector the
screening effect Abar,3D,n is determined individually (see above). The final
screening effect for this ray path equals to the highest Abar, conv or Abar, 3D,n
and is used to calculate the final barrier attenuation Abar.
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obstacles in ray path
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3.7 3D-Reflector
On the following, some situations are described, which may be modeled using either the 3D-reflector or another type of obstacle object or a
combination of obstacles. Some of the situations shown, can neither be modeled using the available types of obstacles or the solution provides just an approximation.
•
surface providing screening upwards with a source/s below or with a lateral obstacles in addition (keyword: „gas station roof“)
screening surface in free space
screening surface in free space
with lateral screening vertical surface
CORRECT: 3D-reflector used for
modeling a elevated screening surface above
the ground, no other screening objects
attached to its edges
WRONG: modeled using several 3D-reflectors (for wall and roof) or vertical barrier
(wall) and 3D-reflector (roof)
The sound power of the source/s below
needs to be increased to consider roof-toground multiple reflections.
Explanation: The ray path is not determined
by common path difference since the joint
wall/roof is not „seen“.
CORRECT: modeling by using a barrier
with a cantilever
The sound power of the source/s below
needs to be increased to consider roof-toground multiple reflections.
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•
3 83
cantilevered canopies at buildings („delivery/supply ramp“)
3
WRONG: modeled the canopy by a 3Dreflector attached to a building
CORRECT: modeled the canopy by a cantilevered barrier attached to the building
Explanation: The ray path is not determined
by common path difference since the joint
3d-reflector - building is not „seen“. The
screening effect in the ray path is determined by that obstacle only providing the
highest screening effect.
Explanation: At the cantilevered barrier the
common ray path, from the vertical and the
horizontal part of the barrier, is considered
for all path directions.
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The sound power of the source/s below
needs to be increased to consider roof-toground multiple reflections.
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•
semi-open or partially open enclosures etc. (source inside)
3
WRONG: modeled using several 3D-reflectors (for wall and roof) or vertical barrier
(wall) and 3D-reflector (roof) or barrier/s
with cantilever
Explanation: The ray path is not determined
by common path difference since the joint
wall/roof is not „seen“.
Even when just using barriers with
cantilever the interior level is not correct
since it does not include roof-to-ground
multiple reflections.
CORRECT: modeled using a building
and a vertical area source modeling the
opening
sound power of the area source does not
include the possibly increased emission due
to internal reflections,
A simplified approach would be to use a
point source instead of a vertical area source
attached to the building‘s facade.
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•
3 85
buildings on top of each other or with changing cross-section with height
or with inclined facades towards the ground
3
WRONG: modeled by a more or less
complex combination of 3D-reflectors
(each being triangles) arranged in free space.
Explanation: With multiple 3D-reflectors in
the ray path, the screening effect is not
based the common path length difference.
In addition, the joints between adjacent 3Dreflectors are not „seen“.
The easiest approach would be to replace
the complex combination of 3D-reflectors
just by a single (possibly floating) barrier,
perpendicular to the ray‘s direction.
CORRECT: using the object „Building“ to
model the exterior shape. Note that the
object „Building“ always raises from the
ground (i.e. not floating buildings possible/
allowed).
This approach represents an approximate
solution based on the available normative
obstacles. Alternatively, an arrangement of
barriers or floating barriers (see chapter
3.2.1) may be used.
see also: see chapter 3.1 "Building", section "Button "Geometry""
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•
comparing the screening effect caused by a 3D-reflector and a common
vertical barrier
3
Since the screening effect by the 3Dreflector results from the shortest path
length difference around all edges (plus lateral diffraction) the path across the top edge
does not necessarily cause the shortest path
length difference.
With the object „Barrier“ the screening
effect always results from the ray path
across the barrier‘s top edge (plus lateral diffraction).
A vertical 3D-reflector standing on the
ground will, therefore, not cause the same
resulting level for each source-receiver combination compared to a barrier with the
same dimensions and location.
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Embankment
The object „Embankment“ traces back historically to the modeling of road
noise (see, for example, RLS-90, /17/). At this time, terrain models were not
commonly used when modeling the sound propagation outdoors.
The embankment has the following properties:
•
In acoustical terms, the embankment represents a double barrier with
parallel diffracting edges at the distance of the „Top Width“ (vertical
spacing of the screen edges).
•
The entered polygon is the baseline of the embankment. A positive slope
generates the embankment to the right of the baseline, a negative slope to
the left of it.
•
The upper edge of the embankment above the reference plane is given by
the parameter „relative Height“.
•
Specifying a height on the dialog Polygon: Geometry raises the baseline
of the embankment by the value entered. In general, the relative height of
the embankment is zero (meter).
•
The embankment acts as a shielding object only, not as a reflecting one.
Embankment in plan view (2D view)
Sectional view of the embankment
For more information regarding the guideline-specific properties of the object „Embankment“, see chapter 6.2.9 "Industry Tab", chapter 6.2.10 "Road
Tab", and chapter 6.2.11 "Railroad Tab".
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3
Embankment in 3D-view
Furthermore, the following properties of the embankment with respect to
terrain modeling are relevant:
•
The slope shown in the 3D view is drawn starting from the baseline and
serves to identify the object as type „embankment“.
•
This slope shown in the graphics does not represent terrain and, therefore, does not influence the ground attenuation. In case a terrain model is
present in parallel, the resulting ground attenuation is just determined by
the terrain shape generated from the terrain model.

The embankment is - despite looking like a terrain formation in the 3D
view - not considered with other terrain-shaping objects (such as height
points and terrain contours) in the triangulation. In particular, the two
screening edges are not triangulated to nearby terrain contours, i.e.
forming a „gap-free“ terrain. This is not an error, but due to the fact
that the embankment is not a terrain-shaping object.
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Dialog Options
3
see chapter 4.4.2 in the manual "Introduction to CadnaA"
Name, Memo-Window,
ID, ObjectTree
This parameter defines the height of the embankment‘s upper edge.
relative Height (above
baseline)
The slope of the embankment being positive is drawn to the right, looking
from first to last point, while a negative value it will be drawn to the left.
Slope 1:
The perpendicular distance of the two parallel screening edges of the doublebarrier.
Top Width (m)
The object is an open polygon and the object height entered on the dialog
Polygon: Geometry refers to the embankment‘s baseline. In general, the relative height is zero (meter). Otherwise, all options on the dialog are available
(see chapter 4.2.2 "Line-like Objects").
Button „Geometry“
Further Information
The command Parallel Object from the context menu of a road enables to
generate an embankment parallel to this road by specifying the distance
(distance road axis - baseline, see chapter 11.19 in the manual „Introduction
to CadnaA“).
Parallel Object
When converting embankments to barriers (e.g. after a barrier optimization)
the height attribute HREL of the embankment is written automatically to the
attribute HA of the barrier (see chapter 11.13 "Convert to" in the manual
„Introduction to CadnaA“).
Conversion into barrier
see also: chapter 3.8.1 Automatically Optimize Noise Barriers
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3.8.1
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Automatically Optimize Noise Barriers
CadnaA is able to determine automatically the required height of a noise
protection wall/barrier which is needed to obey given maximum levels by
means of iterative calculation. The optimization occurs for up to four
evaluation parameters.

3
The wall optimization is limited to a maximum of 100 receivers. In
addition, due to the algorithm applied, no multi-threading is used in the
calculation, thus requiring more computation time - especially with
many active receivers - than a normal calculation at receivers.
Due to the object’s data structure, for such an optimization the object
„Embankment“ is used a nd not the object „Barrier“.
The following example shows the sequence of actions.
Road with a Noise Barrier and a Receiver Point
The represented road exceeds the permitted value at the receiver point.
Therefore a noise barrier shall be constructed in the given position in such a
way that the permitted value is not exceeded.
To perform an optimizing calculation it is necessary to assign the relevant
maximum value as a standard Level (in dBA) to the receiver points. It is not
relevant whether the maximum value has been entered directly or whether it
is determined from the type of land use. In the latter case, it might need to
define suitable types of land use first (see chapter 5.2.1).
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The optimization occurs for up to four evaluation parameters simultaneously.
3
Receiver: standard level assigned
The object „Embankment“ must be given
•
•
a slope of 1:0 and
a top width of 0
Do not enter a value for height - this is what CadnaA is supposed to
determine.
dialog Embankment: all values zero
In the next step we subdivide the noise barrier with the „Break into Pieces“
command from the context menu of the Embankment. In the example 10
sections of identical size have been formed. Now select an appropriate view
in the menu Options|3D-View, e.g. isometric.
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3
Options|3-D-View „Isometric“
In the toolbar of this dialog you can find the symbol „Optimize Barrier“. After clicking, the parameter dialog will open and we can define our strategy of
optimization. The table below shows two possible settings:
Settings A
Settings B
In the upper text box a pattern similar to the group definition can be entered
by which only the walls with identical ID-codes will be integrated into the
optimizing calculation. With settings A all activate embankments are
considered within the optimization, while with settings B only the
embankments with the string Barrier plus two additional characters.
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With every step of the calculation a barrier section is raised by the value given
in „element height“. The shorter the sub-elements are and the smaller the
element height is, the longer the calculation takes. The result of multiplying
„Element Height“ by „Maximum Number of Elements“ is the upper limit
for the height of the barrier.
In the following combo box you can select the name „area“ or enter any
other name, e.g., the product name of a noise barrier. In the first case, the
value 1, in the four subsequent boxes, will remain unchanged and
optimization is executed in a way that the entire surface of the noise
protection wall is minimized. With the setting A the further sample
calculation is executed.
With settings B in the right figure takes into consideration the fact that the
costs per square-meter can depend on the height of the noise barrier because
costs for a foundation have to be apportioned and because, with the
increasing height of the wall, greater wind pressures will have to be withstood. Optimizing is then executed in a way that will minimize the total cost.
Please note that the combo box „Cost/m²“ must not be left without an entry.
The cost schedule of a noise barrier can be saved/deleted with the
corresponding buttons. A saved cost schedule, valid for all projects, will be at
your disposal in the combo box.
After the setting A has been confirmed, the optimizing calculation starts.
Subdivision of the noise barrier into sections of 10m each
- Calculation with the settings A
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An element width of 3 m leads to the following representation.
3
Subdivision of the noise barrier into sections of 3m each
- Calculation with setting B
CadnaA first checks if the maximum value („Standard Level (dBA)“) has
been exceeded at the maximum height of all wall elements - in this case a
message box will pop up. After the corresponding modification of the
configuration the calculation will be restarted.
Please note that with optimizing barriers all settings of the program will be
considered. This is valid for projection, reflection and consideration of all activated elements. Owing to the large number of steps of calculation it is always advisable to deactivate all objects that have no effect on the result.
Another alternative is to cut the relevant part out of the entire project - the
optimized wall will then be imported into the project.
In the following example a noise barrier will be positioned in the given
location in front of a gap in a way that a maximum value, given for the
receiver point behind the gap, can be maintained.
Initial Situation
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In this case the wall is subdivided into 42 elements with a width of 1 m. This
leads to a contour of the upper edge of the wall as shown in the illustration
below. Calculation was executed „strictly according to RLS90“ with buildings
considered as non-reflecting.
3
Optimizing a barrier with calculation „strictly according to RLS-90“
Now, the calculation is repeated with buildings considered as reflecting, considering reflections up to the 5th order. Lateral diffraction will also be included, in opposite to the standard procedure of RLS-90. This is appropriate in
this case as this situation cannot be evaluated correctly ignoring lateral diffraction. As the result shows, a much higher wall would be necessary to meet
this non-trivial situation.
Optimizing a barrier with a 5th order reflection
With the optimization of barriers CadnaA is able to perform an efficient positioning of noise reducing constructions.
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Chapter 4 - Topography
41
Chapter 4 - Topography
The topography (or the terrain profile) has two major effects on the
propagation of sound and on the calculation of sound propagation:
1.
The topography determines the height of sources, of screening objects
and of receivers, provided the height has been specified as relative
height above the ground. The terrain profile may affect significantly, in
particular at short source-receiver distances, the path length difference
and thus the sound ray‘s length. The path length difference and the distance determine the screening (=Abar, i.e. the „barrier attenuation“ by
terrain), the geometrical divergence and the air absorption.
2.
Usually, by evaluating the ray path and the terrain profile, the ground
attenuation is calculated from the ray‘s average height and the distance
source-receiver. This procedure is used by the majority of ground attenuation models which consider the real terrain profile to calculate the
ground attenuation (for example, ISO 9613-2 /8/). More sophisticated
ground attenuation models do not use distinct rays, but consider the
complex ground impedance and add the direct ray and the ray reflected
by the ground, respecting the phase information (e.g. Harmonoise /4/)
.
Any sound propagation software considering the terrain profile during the
calculation evaluates the (absolute) heights of all objects involved in the
sound transmission and having relative object heights using the height
information available from the input data. In principal, this terrain model
may consist of terrain contours, height points, and lines of fault. Moreover,
also objects the absolute ground height which has been specified may
determine the local terrain profile.
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2
4
Practical Hints
4
Chapter 4 - Topography
In practice, often different levels of detail may be discovered with terrain
models which are mostly determined by the availability of input data. Since
the majority of terrain data are imported and not entered manually this data is
mostly used „as is“ without being in the position to adapt the level of detail
to the requirements of sound propagation calculation. Therefore, it may be
useful - especially at a high level of detail - to reduce the complexity of a terrain model in order to save computation time without loosing accuracy of
prediction.
The following points may be relevant when assessing the suitability of an existing terrain model to be used for sound propagation calculation:
Terrain Model from
Terrain Contours
•
In case the terrain model consists of terrain contours, height steps from 1
to 5 m are useful for the purpose of sound propagation calculation. This
means, for example, that adjacent terrain contours differ by 1 meter in
their absolute height. An even smaller vertical stepping leads - in general to longer computation times without causing an additional screening
effect. A vertical stepping being larger than 5 meters may cause relevant
terrain details (such as local cuts or peaks) to be ignored in the calculation of sound propagation.
Examples
3D-Special view of a terrain model with equidistant
height differences between the terrain contour of 1 m
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Chapter 4 - Topography
4
3D-Special view of a terrain model with equidistant
height differences between the terrain contour of 6 m
•
A terrain model consisting of individual height points may have
horizontal distances from 1 to 10 m between the height points. In case
such terrain models are imported from data provided by the local or
national ordnance survey the height points usually form an equidistant
grid. Nevertheless, terrain models may also consist of irregularly
distributed heights points (e.g. resulting from aerial surveys (laser dots) or
from surveys of road cross section).
Terrain Model from Height
Points
Examples
Terrain model of equidistant height points
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Chapter 4 - Topography
4
Terrain model from non-uniformly distributed height points
Terrain Model from
Terrain Contours and
Height Points
•
With a mixed case (i.e. the terrain model consists of both, terrain
contours as well as height points), it cannot be judged per se, whether the
resulting terrain model is useful and not over-determined.
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Chapter 4 - Topography
•
With just a few terrain forming objects - either being terrain contours
and/or height points - it must be assessed in each individual case whether
the terrain model is suitable and valid and whether it can be used in sound
propagation calculation. Remember when having a rough and sketchy terrain model that the triangles generated in the triangulation may be very
large and can, consequently, not represent properly the real terrain shape
(see chapter 6.2.6). The result will be a terrain model with spatially varying
precision representing the real terrain just to a minor extend.
Terrain Model with only
a few terrain forming
objects
4
Example
Terrain model with a few, unevenly distributed terrain contours
(solid lines) with non-equidistant height differences (2 to 4 m).
The triangulation (dashed lines) generates large triangles of
terrain with constant slope. In these areas, the digital terrain
model represents the terrain‘s real profile only approximately.
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4
Terrain Models and
Project Area
4
Chapter 4 - Topography
•
Terrain models should extend beyond the actual project area in order to
cover also ray paths propagating tangentially along the actual project area
(i.e. the area where the sources, the obstacles and the receivers are
located). Otherwise ray paths may exist propagating across terrain parts
being outside of the actual terrain model. In those cases, the terrain‘s
slope and thus the resulting screening effect by the terrain as well as the
ray‘s average height (ground attenuation) would be at random in this area
and depending on the limit‘s corners (see chapter 9.1).
Example
Town model with a terrain model being too small:
The rays (in blue color) extending from relevant sources (in this case
the road sections on the right) cross terrain without explicit height defined
by terrain forming objects (e.g. terrain contours).
The resulting screening effect of the triangulated terrain contours (dashed lines)
is at random, because it also depends on the location of the project‘s limits.
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Chapter 4 - Topography
In order to assess the required and reasonable level of detail, it is useful to
know the software-internal procedure when evaluating digital terrain models
in the process of sound propagation calculation. In the following, this processing of height information in CadnaA is described.
•
By default, each section of a terrain contour - whether it was entered or
whether it results from triangulation - generates a screening edge with this
line as the top edge (holds also for lines of fault). This replacing screen
stands perpendicular to the reference plane having an absolute height of 0
meters. The entered height of a terrain contour (on dialog Geometry) is
always interpreted as an absolute height.
•
When the terrain is solely modeled by using height points, these will not
provide any screening, but only the terrain contour lines resulting from
the triangulation. In this case, ensure that the option „Explicit Edges
Only“ on the „DTM“ tab (see chapter 6.2.6) is not activated.
•
Lines of fault are superfluous in conjunction with the triangulation, since
they can be replaced by two parallel terrain contours. Otherwise, the
heights left/right has to be specified and are not automatically derived
from the actual terrain model.
Prior to the calculation of propagation CadnaA calculates the absolute
heights of all vertices of all objects:
•
For objects with specified relative heights, the absolute level of the terrain
at the base point and the height above the reference plane are determined
using the local terrain height as resulting from the triangulation of the terrain forming objects.
•
For objects with absolute heights, this height represents the final height.
•
For objects the height of which has been specified using the height attribute option „Height above Roof“ the same procedure as with relative
heights applies, while, in addition, the height of the surrounding object is
considered when determining the absolute heights.
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Software-internal
Procedure
4
8
4
4
Chapter 4 - Topography
•
For objects that have been entered using the height attribute „absolute
Height/Ground at every Point“ just the object‘s height is taken into
account by default. In order to respect the ground it requires that the
option „Objects with Ground at every Point influence DTM"“ is
activated (see chapter 6.2.6).
•
The object height is evaluated
 for line-like objects (i.e. open polygon lines, e.g. line sources, roads,
railways, barriers etc.) for each vertex point of the polygon,
 for area-like objects (i.e. closed polygons, e.g. for area sources, parking
lots etc.) for each vertex point of the polygon,
 for buildings (being a closed polygon) just for the first polygon point.
This refers to the first polygon point as listed on the dialog Geometry
of the object „Building“ (first point).
Within the calculation of sound propagation a sound ray reaching from the
source to the receiver intersects with all intervening terrain contours and lines
of fault (and also with all other screening objects). In this course, the path
length difference and, consequently, the screening effect caused by terrain
edges and other objects is determined. In addition, from the height of the
sound ray above the terrain at all intersecting points and from the path
lengths between these points the average ray‘s height is calculated by iteration, finally resulting in the ground attenuation. The terrain height at the
source and the receiver are also considered.
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Chapter 4 - Topography
4.1 Terrain generating Objects
4.1
49
Terrain generating Objects
In general, the specification and the generation of a terrain model makes use
of the following terrain forming objects:
•
terrain contour or „contour line“ (see chapter 4.1.1)
•
height point (see chapter 4.1.2)
•
line of fault (see chapter 4.1.3)

The object „Line of Fault“ is superfluous when generating terrain by
triangulation and should, therefore, no longer be used in this case.
Furthermore, all objects having specified the local terrain height in the
object‘s geometry may determine the terrain height. This holds for the
following object types and their respective geometry options:
•
point objects: The option „Ground Height: input of value (m)“ is
selected. In this case, the entered value is relevant (see chapter 4.2.1).
•
line and area objects: The option „absolute Height/Ground at every
Point“ is selected. In this case, the values specified in column „Ground“
of the geometry table are relevant (see chapter 4.2.2 and 4.2.3).
However, these objects are relevant when generating the terrain as long as the
option „Objects with Ground at every Point influence DTM“ on the „DTM“
tab is activated (see chapter 6.2.6). In this case, the terrain heights of these
objects determine the terrain‘s level at this location.
Otherwise these objects, even though an individual terrain height has been
specified, will be ignored when generating the terrain model. In this case, the
object height results from the sum of the local terrain height and the object‘s
relative height. In case an absolute height has been entered for the object,
however, the entered local terrain height is ignored.
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Example
Chapter 4 - Topography
4.1 Terrain generating Objects
The height of a point and a line source are specified using the options
„Ground Height: input of value (m)“ and „absolute Height/Ground at every
Point“.
Option „Objects with Ground at every
Point influence DTM“ activated
Option „Objects with Ground at every
Point influence DTM“ deactivated
The entered ground height in the object‘s
geometry is considered when triangulating the
terrain.
The entered ground height in the object‘s
geometry is not considered when triangulating
the terrain.
4
blue: point and line source
blue: point and line source
red: triangulated terrain edges
(limits: 1000 x 1000 m)
red: There is just a single terrain edge at a
height of 0 m between the corners of the limits (from (x,y)=(0,0) to (1000,1000) m).
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Chapter 4 - Topography
4.1.1 Contour Line
4.1.1
4 11
Contour Line
The object „Contour Line“ is used - besides the object „Height Point“ - to
model the topography resp. the terrain‘s profile.
By the polygon of a contour line (terrain contour) a defined height above the
reference plane is defined. The height profile of the polygon is specified as
with line-like objects (see chapter 4.2.2). Prior to the actual calculation of
propagation, the final terrain profile is interpolated using the heights assigned
to the terrain forming objects, applying the procedure as specified on dialog
Calculation|Configuration, „DTM“ tab (see chapter 6.2.6) By default, the
triangulation method is applied.
In the calculation of sound propagation, the terrain profile may cause screening and affect the ground attenuation. The absolute level of objects whose
height has been entered as relative heights is determined from the object‘s
height and the terrain model. When calculating sound propagation the
contour lines are considered as being the upper edges of barriers. Terrain
contours generated by interpolation (e.g. by triangulation) between the
entered contour lines cause, by default, also screening (provided the option
„Explicit Edges Only"“ on tab „DTM“ is deactivated, see chapter 6.2.6).

When calculating the screening by terrain no lateral diffraction is
accounted for.
On the table Contour Line (on menu Tables|Obstacles) just the first and
the last point are listed (with option „Interpolate Height from First/Last
Point“). The height entered is always interpreted as absolute height.
Dialog Contour Line
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Chapter 4 - Topography
4.1.1 Contour Line
Dialog Options
4
Name, ID code, MemoWindow, ObjectTree
see chapter 4.4.2 in the manual „Introduction to CadnaA“
Option "Use Points as
Height Points"
This option offers to save a terrain model made from height points as
contour lines where the vertex points of each contour receive the height of
each height points (with geometry option „Height at every Point“).
In order to convert height points into a so-called height point cluster, see
chapter 4.1.2, section "Use Contour line as Cluster of Height Points".
By activating this option, the heights points making up the contour line are
displayed in the graphics using the height point‘s symbol, but using the color
setting for contour lines.
Button "Geometry"
see chapter 4.2.2 of this Reference Manual
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Chapter 4 - Topography
4.1.1 Contour Line
When having imported terrain contours from external file formats it may be
necessary to toggle the height attribute HA_ATT (see chapter 1.1 in the manual „Attributes, Variables, and Keywords“) from „Interpolate Height from
First/Last Point“ to „absolute Height at every Point“. Since the height information of terrain contours always represents absolute heights, changing the
height attribute may not be possible by using the default attribute abbreviations (see chapter as mentioned above).
In this case, proceed as follows:
•
Select the command Modify Objects from the context menu of the
CadnaA main window.
•
Select the action „Modify Attribute“ for the object type „Contour Line“.
•
From the subsequent dialog, select a height attribute HA_ATT.
•
Activate the option „Replace Strings“ and delete the entry under „Replace
with“.
•
Click OK and confirm the action with „All“.
Afterwards, the height attribute of the contour lines is set to „absolute Height
at every Point“.
Changing the height attribute HA_ATT of terrain contours
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Toggling the height
attribute of terrain
contours
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14
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Chapter 4 - Topography
4.1.1 Contour Line
4
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Chapter 4 - Topography
4.1.2 Height Point
4.1.2
4 15
Height Point
The object „Height Point“ is used - besides the object „Contour Line Point“
- to model the topography resp. the terrain‘s profile.
Note that when modeling terrain by using height points - in contrast to
contour lines and lines of fault - a screening effect will just result from the
triangulated terrain edges generated between the height points. This requires
that the option „Triangulation“ in the dialog Calculation| Configuration,
tab "DTM" (see chapter 6.2.6), is selected and the option „Explicit Edges
Only“ is deactivated.
Terrain model just made of height points,
option „Explicit Edges Only“ deactivated
Terrain model just made of height points,
option „Explicit Edges Only“ activated
Result: A shielding effect by triangulated terrain edges occurs.
Result: No screening effect occurs.
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Chapter 4 - Topography
4.1.2 Height Point
By using height points a defined height above the reference plane is assigned.
The height is specified according to the geometry of point-like objects. The
absolute height of objects having been entered using relative heights is calculated using the ground height resulting from the terrain model.
4
Dialog Height Point
Dialog Options
Name, ID code,
Memo-Window,
ObjectTree
see chapter 4.4.2 in the manual „Introduction to CadnaA“
x (m), y (m)
coordinates of the height point in the selected coordinate system
Height z (m)
absolute height of the height point
Button „--> RefPoint“
see chapter 4.2.4, section "Filling the List of Reference Points"
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Chapter 4 - Topography
4.1.2 Height Point
Many height points require a large amount of memory and, thus, increase the
size of the project file (also due to the fact that for each height point the
name and the ID have to be stored separately). To save memory you may
convert the height points into contour lines using the command Modify Object (action „Convert to“, object type „Height Points“). This action generates a cluster of height points where each cluster may consist of up to 1000
height points joined to a contour line. The contour lines can be converted
back again into individual height points.
Use Contour line as
Cluster of Height
Points
•
Open the file HP.cna containing about 4,000 height points.
 Examples\04_Topog-
•
Open the dialog Modify Objects, selected the action „Convert to“ for
object type „Height Point“ and confirm by OK.
•
On the dialog Convert Objects select the target object type „Contour
Line“.
•
Click OK and confirm by „All“.
•
Open from the Tables|Obstacles menu the table Contour Lines.
4
raphy\HP.cna
The height points have been converted into five contour lines. The file size
has been reduced by this operation by nearly a half.
•
Move the table a little aside and mark some table rows one after the other.
The respective height point cluster will be highlighted.
An ASCII file with xyz coordinates of height points can either be imported
using the command File|Import, import format „ASCII-Objects“ (see
chapter 7.2.18 "ASCII-Objects"), or via the ODBC-interface (see chapter 7.3
"Import via ODBC Interface").
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Import ASCII-File as
Height Points
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Chapter 4 - Topography
4.1.2 Height Point
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Chapter 4 - Topography
4.1.3 Line of Fault
4.1.3
Line of Fault
The object „Line of Fault“ is superfluous in conjunction with the terrain generation by triangulation (see chapter 6.2.6) and should, therefore, no longer
be used in this case.
When using the triangulation, the same effect on the terrain model is caused
by two parallel contour lines, the one having the height of the lower, the other
the height of the upper terrain level.

4
The line-of-fault has been used in conjunction with the historical methods for generating a digital terrain model (options „Search Contour
Lines (Average)“ and „Search Contour Lines (Local Inclined Plane)“ on
dialog Calculation|Configuration, „DTM“ tab (see chapter 6.2.6) to
cause a jump in terrain height on both sides by the nearest contour lines
or other height points (e.g. base points of buildings).
Dialog Line of Fault
Dialog Options
see chapter 4.4.2 in the manual „Introduction to CadnaA“
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Name, ID code, MemoWindow, ObjectTree
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Chapter 4 - Topography
4.1.3 Line of Fault
Button "Geometry"
4
Dialog Geometry of a Line-of-Fault
•
option „absolute Height at every Point“: After double-clicking into a row
of the polygon point table, the absolute height to the left and to the right
of the line-of-fault can be entered.
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Chapter 4 - Topography
4.2 Object’s Geometry
4.2
Object’s Geometry
CadnaA offers to specify the local ground height within the geometry of ob-
jects (option „Ground Height“: Input of Value (m)“ or option „absolute
Height/Ground at every Point“). Thus, depending on the setting of the
option „Objects with Ground at every Point influence DTM“ on the „DTM“
tab, these objects will influence the resulting terrain model (see chapter 6.2.6).
4.2.1
4
Point-like Objects
The geometry of point objects (such as point source, receiver etc.) is specified
by the coordinates x, y, and the (absolute) height z. These values are listed
on the respective columns of the corresponding object table (see chapter
11.1).

For the object „Cylinder“ there are, besides the x and y coordinates, the
cylinder‘s center and its radius.

For height points the entered height (z) is always interpreted as absolute
height.
Dialog Point-Geometry with point objects
On the dialog Point Geometry the height h (m) can be entered relative, absolute or relative to a building‘s roof. From the height h and the ground
height the absolute height z results.
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Dialog Options
Point Geometry
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4
Options for Height
Chapter 4 - Topography
4.2.1 Point-like Objects
•
Option „relative“: height (m) at the coordinate point (x, y) above ground
level. The (absolute) level of the ground results:
 from terrain forming objects (contour lines, height points, lines of
fault)
 from the standard height as specified on the „DTM“ tab (menu
Calculation|Configuration, see chapter 6.2.6) and
 from the method used for generation of the terrain between the
height defining objects (by triangulation per default).
4
Ground Height (m) &
list box
•
Option „absolute“: height above a reference plane, usually above mean
sea level (MSL). The reference height MSL might not the same to
different, even neighboring countries because different definitions and
references are in use.
•
Option „Roof“: In order to facilitate the height specification of sources
on top of roofs of buildings a relative height above roof level can be
entered using this option. When the source is within a building‘s outline
the final height results from the sum (building height + height above
roof).
The input box „Ground Height“ is just available with the option „Input of
Value (m)“ selected.
•
Calculate from DTM (default): With this option, the ground height is calculated by evaluating the present terrain model.
•
Use next building: With this option, the ground height of the nearest building facade within radius of 1.5 m is used. With no building facade be
located within this radius the height at this location is also calculated by
evaluating the present terrain model.
•
Input of Value (m): The ground height at this location can be specified by
entering a value.
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Chapter 4 - Topography
4.2.1 Point-like Objects
Besides the coordinates X and Y (m) the diameter (m) of the building
evaluation symbol can be specified.

4 23
Geometry Options for
Object „Building
Evaluation“
The diameter of all building evaluation symbols in a project can be
changed via the respective table (see Tables menu, Other Objects|
Building Evaluation).
4
Dialog Geometry of the Building Evaluation Symbol
This option enables to place a building evaluation symbol outside of the
building‘s outline. When this option is activated the building evaluation symbol can be placed outside of the building without losing the link to this building. The original coordinates are saved as well.
Procedure:
•
First place the building evaluation symbol inside of a building‘s outline.
•
Open the dialog Geometry and activate the option „Use different
Calculation Point“.
•
Close all dialogs with OK and move the building evaluation symbol outside of the building‘s outline. The calculation point is indicated by a auxiliary polygon.
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Option „Use different Calculation Point“
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Chapter 4 - Topography
4.2.1 Point-like Objects
4
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Chapter 4 - Topography
4.2.2 Line-like Objects
4.2.2
Line-like Objects
Line-like objects (e.g. line source, road, railway) are defined by a sequence of
polygon segments or, respectively, by a sequence of points making up the
polygon. The first and the last point of the polygon may have the same or a
different height (being relative, absolute or relative heights referring to a
building roof). In this case, the height of intermediate polygon points is determined by linear interpolation (option „Interpolate Height from First/Last
Point“). Alternatively, for each point of the polygon may a different absolute
height may be defined.

4
For contour lines the entered height (z) is always interpreted as an absolute height.
Dialog Geometry of a Line Source
List of polygon points: Shows the coordinates x, y, z and the ground height at
the respective point. A double-click into a table row opens the dialog Polygon Point. Using the command from the context menu of the table offers for example - to delete or insert polygon points.
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Dialog Options
Polygon: Geometry
26
4
List Box Height
Chapter 4 - Topography
4.2.2 Line-like Objects
option „Interpolate Height from First/Last Point“:
•
relative: height in meters (m) above terrain level at the coordinate (x, y).
The (absolute) height of the ground results from:
1. the height of objects forming terrain (contour lines, height points, lines
of fault),
2. from the standard height specified on "DTM" tab (menu
Calculation|Configuration, see chapter 6.2.6) and
3. by the method applied to from terrain between the objects defining terrain height (e.g. by triangulation).
4
•
absolute: Height above a reference plane, as a rule above mean sea level
(MSL). The MSL height does necessarily correspond for different, even
neighboring countries since different definitions and references are used.
•
Roof: This option facilitates the input of a height for sources on top of a
building's roof. The relative height above the roof plane is entered. For a
source within the building's border the source height results from the sum
(building height + height above roof).
option „absolute Height at every Point“: When this option is selected the
absolute height Z can in addition be edited in the list of polygon points or via
the dialog Polygon Point.
option „absolute Height/Ground at every Point“: When this option is
selected the ground height, besides the absolute height Z, can be edited in the
list of polygon points or via the dialog Polygon Point.
2D-Length
length of the polygon projected into the xy plane
Station
In order to generate station marks alongside of line-like objects an initial station value (in meters) can be specified (see chapter 9.11.4). The option "ascending/descending" defines as to whether the stationing starts increasing or
decreasing from the present location.
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Chapter 4 - Topography
4.2.2 Line-like Objects
Initially, when entering the objects „vertical area source“ (see chapter 2.1) and
„barrier“ (see chapter 3.2) in the graphics, these are represented by a 2D
polygon having no height. The height (or the z-coordinate) of the polygon
points for these objects (as entered via the Polygon: Geometry dialog) refers to the top edge of the object. The other dialog options comply with
those for line-like objects in general.
Additional information for objects
„vertical area source“
and „barrier“
With floating barriers, the z extend (see chapter 3.2.1) describes the vertical
height difference of the lower edge to the top edge as entered on the dialog
Polygon: Geometry.
vertical area source &
barrier: z-extension

The z-extend counts positive downwards!
Consequently, the bottom and top edge are always parallel and cannot be distinguished in the 2D-plan.
z-extend of a floating barrier: In this example, the barrier extends
at all polygon points 3 m downwards from the top edge.
When entering the object „Vertical Grid“ (see chapter 5.3.6) a height of the
top edge of 20 meters is set by default. The object can consist of two points
only (see dialog Polygon: Geometry). Further polygon points will be ignored.
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Additional information for object
„Vertical Grid“
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Height Extend of the
vertical Grid
Chapter 4 - Topography
4.2.2 Line-like Objects
The vertical grid extends from the height of the top edge (as specified on dialog Polygon: Geometry) down to the ground. Grid points below the terrain, however, are not displayed in the grid. Depending on the grid spacing,
this causes more or less white areas on the vertical grid.
Flat terrain:
The vertical grid
extends to the ground.
4
The dots indicate the
grid points (grid
spacing (1 by 1) m.
Non-flat terrain:
The vertical grid
(spacing (1 by 1) m also
extends down to the
ground, but grid areas
where the grid point is
below the
terrain profile are not
displayed (white color).
same as above, but now
with a coarser grid
spacing of
(5 by 5) m.
Again, the grid areas
where the grid point is
below the
terrain profile are not
displayed (white color)
Additional Dialog
Options for Road &
Rail
Besides the default geometry options of line-like objects, there are additional
dialog options available for the objects „Road“ (see chapter 2.4.1) and „Railway“ (see chapter 2.6.1).
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Chapter 4 - Topography
4.2.3 Area-like Objects
4.2.3
Area-like Objects
The geometry of area-like objects (e.g. area source, parking lot, building,
ground absorption) is defined by a list of polygon points with coordinates x,
y and the height z. Area-like objects represent with respect to their geometry
a closed polygon. In the same way, spatial objects (i.e. objects having a height,
e.g. buildings) are defined by a closed polygon representing the building‘s
outline in 2D projection and a height in addition.
4
Dialog Geometry of an area source
List of polygon points: shows the coordinates x, y, z and the ground height at
the respective point. A double-click into a table row opens the dialog Polygon Point. Using the command from the context menu of the table offers for example - to delete or insert polygon points.
Dialog Options
Polygon: Geometry
The options are consistent with those of line-like objects (see chapter 4.2.2).
In addition, the 2D surface is displayed:
List Box Height
area (in m²) of the polygon projected into the xy plane
2D-Area

For the source „Parking Lot“ a height of 0.5 m is used automatically
which is added to the entered height upon calculation.
Besides the geometry options for area-like objects as described above the following further points are noteworthy with buildings:
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Additional Information for object
„Building“
30
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Chapter 4 - Topography
4.2.3 Area-like Objects
•
With reference to the underlying calculation procedures buildings are, in
fact, modeled from a sequence of barriers, forming a closed polygon in
the xy plane and making up an „open“ box, having no roof which is acting as a reflecting surface. Therefore, the directivity index K0 or D of
point, line or area sources that are located within a building‘s outline is
considered based on their respective the height above the ground (and
not above the roof, since there is no actual roof accounted for).
•
When a building has assigned different heights at its polygon points, the
height of building will be determined based on the height of the first
polygon point of the building (see chapter 11.7 "Modify Order of Points"
in the manual „Introduction to CadnaA“).
•
When the option „Roof“ is activated, an area source that is located inside
a buildings outline will receive a uniform height at all polygon points
based on the height at the first building point. If necessary, select the
option „absolute height at every Point“.
•
A building may also be defined with a relative height on top of a further
building. To this end, activate the option „Roof“ for the inner building. In
this case, the input sequence is not relevant. The underlying calculation
standards just calculate the screening effect correctly with smaller buildings on top of larger buildings (like a pyramid), but not vice versa.
4
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Chapter 4 - Topography
4.2.4 Additional Input Features
4.2.4
Additional Input Features
In order to generate a proper sequence of a (open or closed) polygon curve
(e.g. a terrain contour) additional polygon points may be entered, the heights
of which are unknown. CadnaA can determine these unknown heights by
linear interpolation.
Proceed as follows:
•
Enter the polygon (e.g. a terrain contour or „contour line“) with the
required number of polygon points in order to generate a proper curve.
•
Select on the dialog Polygon: Geometry the option „absolute Height at
every Point“.
•
Enter the known absolute heights in column „z (m)“ at the known xy
locations.

•
4 31
Move both dialogs, the dialog Polygon: Geometry and the object dialog a little aside in order to see the polygon object in the main window.
The currently selected polygon point is highlighted.
Select in the table of points, those points one-by-one having an unknown
absolute height and press the space bar to delete the default value 0 m.
Dialog Geometry (here of a terrain contour): absolute height z
at a polygon point has been deleted using the space bar
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Interpolate unknown
heights of polygon
points
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Chapter 4 - Topography
4.2.4 Additional Input Features

4
Do not use the DEL key, since then the polygon point is deleted from
the table.
•
When closing the dialog CadnaA will recalculate the value by linear interpolation.
•
Reopen the dialog Geometry to display the interpolated value/s.
Dialog Geometry: The absolute height z
was interpolated between two polygon points.
Alternatively, only the polygon points with known heights can first be
entered and then using the editing of polygons (see chapter 4.3.1 in the
manual „Introduction to CadnaA“) additional points will be entered
graphically. Then delete the column "z (m)" of the polygon point list with the
space bar the initial value 0 m.
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Chapter 4 - Topography
4.2.4 Additional Input Features
Coordinates can be copied from the geometry of point objects as well as of
polygon objects (lines and areas) to a list of reference points for later use.
Consequently, there is no need to write down coordinates manually in order
to enter them later.
Filling the List of
Reference Points
Examples for using a list of reference points include the transfer of
coordinates to other objects with transformations (option „Match Points“,
see chapter 7.1.4) or the acquisition of coordinates when calibrating a bitmap
(see chapter 10.1.1 in this manual and chapter 9.1 in the manual „Introduction to CadnaA“).
In order to make use of a list of reference point with point objects proceed as
follows:
•
Click on button „Geometry“ in the dialog of point objects to open the
dialog Point-Geometry.
•
Click on the button „--> RefPoint“ to copy the coordinates of the point
to the reference point list.
•
From the subsequent dialog Reference Points, select one of the four
available reference points where the data will be copied to.
Dialog Reference Points: reference point 2 is selected
•
Close the dialog Reference Points by OK.
•
By clicking again on button „--> RefPoint“ you can check whether the
coordinates have been copied.
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Transferring reference
points for point objects
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Chapter 4 - Topography
4.2.4 Additional Input Features
4
Dialog Reference Points: Point coordinates have
been copied to the reference point 2
Transferring reference
points for polygon objects
In order to use the list of reference point list with polygon objects (lines or
areas) proceed as follows:
•
On the object‘s dialog click the „Geometry“ button.
•
Double click in the table of polygon points into the row whose
coordinates are to be copied as a reference point.
Dialog Polygon: Geometry: After a double click in a
table row the dialog Polygon Point opens.
•
Click the button „--> RefPoint“ to copy the coordinates of this point to
the list of reference points.
For additional features see section „List of reference points for point
objects“ (see above).
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Chapter 4 - Topography
4.2.4 Additional Input Features
When entering line-like and area-like objects in the graphics (not for cylinder)
right angles between individual polygon sections may be enforced.
4 35
Generating Orthogonal Polygons
Proceed as follows:
•
Select - for example - the object „Building“ from the toolbox.
•
Enter the first polygon point by clicking the mouse button.
•
Now, press the Shift key.
Now, the mouse cursor is trapped in fixed steps of 90 degrees with respect to
the preceding polygon section.
•
Click while holding down the Shift key at the position of the next polygon
point.
•
Proceed analogously till the last polygon point has been entered.
•
Click with the right mouse button to close the building‘s polygon.
By the last step, the first and the last point of the building are joined
automatically and, thus, closing the building‘s polygon.

When drawing rectangles, it is useful to start with the longer side. After
having entered the third point for the shorter side, position the mouse
pointer on the starting point. Please click on the starting point, to enter
the third longer side automatically with it‘s correct length. Close the
rectangle by a final click using the right mouse button. This procedure is
recommended especially when entering buildings having a rectangular
outline.
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4.2.4 Additional Input Features
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Chapter 4 - Topography
4.3 Topography-specific Functions
4.3
Topography-specific Functions
In this chapter, specific features (with examples) are described applicable
when generating and editing digital terrain models in CadnaA.
Preliminary Note
In each of the following chapters the range of application and the effects of
each feature are described. The presentation focuses on the software-related
functions and procedures, also addressing possible user criteria when applying a feature or function. Please consider that just the mere existence of a feature or function does not mean, however, that it may be appropriate to be
applied in a particular case.
4
The decision, which feature or function may apply in a particular case cannot
be taken by the software itself, but remains in the responsibility of the user.
The subsequent chapters cover the following program functions:
•
see chapter 4.3.1 "Fit Objects to DTM"
•
see chapter 4.3.2 "Fit DTM to Object"
•
see chapter 4.3.3 "Generate Terrain Contours from Height Points"
•
see chapter 4.3.4 "Generate a Grid of Height Points from Terrain Contours"
•
see chapter 4.3.5 "Generate Cluster of Heights Points from Bitmap"
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Functions
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4
Further Features for
processing Terrain
Data
Chapter 4 - Topography
4.3 Topography-specific Functions
In addition, further software features are available which can be used when
importing terrain data or in order to modify existing an terrain model. In
each particular case the user decides whether a specific software feature is
useful and appropriate.
•
4
see chapter 11.9 "Simplify Geometry" in the manual „Introduction to
CadnaA“
•
see chapter 15.6 "Close Polygons" (requires option X or XL)
•
see chapter 15.7 "Delete Height Points" (requires option X or XL)
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
4.3.1
Fit Objects to DTM
The basic functions of this command are described in chapter 11.24 of the
manual „Introduction to CadnaA“.
The data on object heights (e.g. roads, buildings) and terrain height (i.e.
height points, contour lines) often originate from different sources. In practice it occurs quite often that the given object heights (e.g. the road‘s height)
does not correspond with the terrain heights.
In these situations, CadnaA can fit the object height (e.g of a road or roads
or other line- or area-like objects) to the terrain height by means of the command Fit Object to DTM. With this, new vertex points will be generated of
the object‘s geometry, the height (z coordinate) of which will be adjusted to
the local ground level.
When using this command, it is assumed that the terrain model and, thus, the
local height (z coordinate, i.e. the absolute height) is correct and relevant.
This implies that the actual object heights are less correct and less relevant
than the local terrain height.
The decision whether the object heights or the terrain model is/are relevant
or not, cannot be decided by the software, it is up to the user.
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
Consequences
With regard to the effects caused by this command we will distinguish linelike and area-like objects in the following.
Line-like Objects
Examples of this type of object are line sources, roads or railways.
For these objects, the entered polygon line represents the central axis of the
object (especially with roads and railways). This means that even with a varying road width, the geometry (and hence the height) is known for the center
line only. Thus, fitting to the terrain can, therefore, just occur for this center
line, since the heights at the road‘s curbs (or on the edge of the railway track)
are unknown. This holds - regarding roads - especially when a lateral slope
has been entered for the road (see chapter 2.4.1). Even in this case, fitting to
the terrain just occurs for the road‘s center line.
The consequence is - regardless whether a lateral slope has been entered or
not - after using the command Fit Object to DTM the both road curbs may
either be covered by terrain or are floating above the ground. When no lateral
slope has been entered the road surface is assumed to be flat. Furthermore,
this may have the additional consequence that two emission lines of the road
may also be covered by terrain or may float above the ground. In case a lateral slope has been entered it will be kept when using the command Fit Object
to DTM. In both cases - with or without a lateral slope - no adaptation of the
road curbs to the local terrain height occur.
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
Example
4
Road with two contour lines
3D-Special view
The height is known at the polygon points of
the road. Here the two points are located in
flat terrain (the area between contour line at 0
m and the corners of the limits).
The road is covered by the terrain because
there is no height defining polygon points of
the road within the hill area.
When executing the command Fit Object to
DTM additional polygon points are inserted
to the object‘s geometry at all intersections
with explicit or triangulated terrain contours.
Their local ground height results from the terrain model.
3D-Special view
CadnaA - Reference Manual
The road is no longer covered the terrain. The
fitting of the object‘s geometry is based on the
center line of he road.
42
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
Nevertheless, the road may still be overlapped by terrain or be hovering
above the ground at the road‘s curbs.
4
After applying the command Fit Object to DTM the road‘s curbs
may still be covered by terrain or float above the terrain.
With a road having a lateral slope (in this case 20%) the fitting
to the DTM just occurs for the road‘s center line.
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
Examples of this type of objects are area sources and parking lots.
Area-like Objects
With area-like objects, explicit polygon points just exist for the perimeter line
of the source. Inside of the area object, however, there are no polygon points
the height of which could be fitted to an existing terrain model.
Consequently, with an area-like object just a defective fitting to a complex terrain may result when using the command Fit Object to DTM.
4
Example
An area source in a complex terrain
before applying the command
Fit Object to DTM
Situation after applying the command Fit
Object to DTM:
The polygon points of the area source‘s
outline have been fit to the local terrain
height. However, the areas inside the
source‘s outline are still below terrain.
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Chapter 4 - Topography
4.3.1 Fit Objects to DTM
In order to properly fit area sources to the terrain do not use the command
Fit Object to DTM, but enable the option „Area sources with constant
relative height follow terrain“ from the „DTM“ tab, on the Calculation|
Configuration menu (see chapter 6.2.6).
4
Fitting an area source to the terrain with option
„Area sources with constant relative height follow terrain“ enabled
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Chapter 4 - Topography
4.3.2 Fit DTM to Object
4.3.2
Fit DTM to Object
The basic functions of this command are described in chapter 11.23 of the
manual „Introduction to CadnaA“.
By the command Fit DTM to Object (in the context menu of objects or as
an action on the Modify Objects dialog) the entire terrain model will get
modified by cutting existing and inserting new terrain contour lines.
When using this command, it is assumed that the current height (height z, i.e.
the absolute height) of the object/objects, is correct and relevant to which
the terrain model is going to get fit. This implies that the actual terrain model
is assumed to be less correct and less relevant than the object height/s.
The decision whether the object heights or the terrain model is/are relevant
or not, cannot be decided by the software, it is up to the user.
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Example
Chapter 4 - Topography
4.3.2 Fit DTM to Object
In this example, the command Fit DTM to Object causes to „clear up“ the
road‘s surfaces from overlapping ground. Just from the existing data,
however, it is not possible to assess whether the resulting geometry
corresponds to reality in this area or not.
4
Terrain model prior to execution of the
command Fit DTM to Object
(roads having relative heights)
3D-Special view of a road canyon prior to execution of the command (roads partially covered by terrain)
Terrain model with additional, road-parallel
contour lines after execution of the
command Fit DTM to Object
3D-Special view of a road canyon with
terrain cuts after execution of the command
Fit DTM to Object
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Chapter 4 - Topography
4.3.2 Fit DTM to Object
Using this command may cause severe changes to the original terrain model
without being able to decide in advance, whether the resulting terrain model
is more „real“ than the previous one. Accepting that a measure for the accuracy would be the „real terrain profile“, it would require in any case that a terrain model with a finer resolution would be available for each project in order
to examine the deviations. This is, in practice, not possible for time and cost
reasons.
Consequences
4
It is, therefore, strongly recommended to not use this command routinely,
but only in situations where a preliminary study has shown that the resulting
heights difference before and after applying the command are deemed acceptable.
In the following, a procedure is described to display the height differences on
the grid before and after executing the command Fit DTM to Object. The
situation as shown in the former example will be used assuming that the two
situations are available in separate files:
1.
A file with contour lines prior to execution of the command.
2.
A file with contour lines after execution of the command.
Proceed as follows:
•
First, open the file containing the contour lines before executing the command Fit DTM to Object.
•
Now, sort the values in column „Height, top (m)" of the table height line
in ascending numerical order to determine the range of values of the
altitude.
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Chapter 4 - Topography
4.3.2 Fit DTM to Object
4
Sorting the first heights of the contour lines in ascending order
•
Check by scrolling in the table for the minimum and maximum height.
•
Open the dialog Grid Appearance from the Grid menu and enable the
„Level Range“ option.
•
Enter a value below the minimum and above the maximum height as
established by the scrolling from above (e.g. „70“ and „210“ for 70 m and
210 m).
•
Enter a class width of 5 m (meters and not dB in this case).
Thus, the interpolation will be run using these specifications. Make sure prior
to the calculation that no grid interpolation is set on the „General“ tab (menu
Configuration|Calculation).
•
Enter on the Grid|Specification menu a receiver spacing of 5 m by 5 m.
•
Now, execute the grid calculation by selecting the command Calc Grid
from the Grid menu.
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Chapter 4 - Topography
4.3.2 Fit DTM to Object
•
Toggle via the list box on the toolbar to the ground grid.
•
If necessary, adjust the grid appearance (see chapter 5.3.2).
•
Save the grid via menu File|Save As (e.g. using the filename grid prior
DGMtoObj.cnr).
•
Save the CadnaA file using a new name.
Afterwards we proceed in the same way with the file the contour lines after
execution of the command Fit DTM to Object.
•
Save the grid via the menu File|Save As (e.g. using the filename grid after
DGMtoObj.cnr).
•
Save this CadnaA file under a new name.
Now, the difference grid is generated from the grid files.
•
Open the file containing the contour lines after execution of the
command Fit DTM to Object, the dialog Grid Arithmetic from the
Grid menu.
•
Download both grid files and execute operation illustrated below with the
ground grids r1g and r2g from.
Generating the difference grid r1g-r2g
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Chapter 4 - Topography
4.3.2 Fit DTM to Object
•
If required, adjust the grid appearance by selecting a suitable color palette
for evaluation parameter LP1 (see chapter 5.3.2).
The following diagram
„pal_0_5_step_05".
makes
use
the
provided
color
palette
4
Grid with height differences (grid spacing 5 m by 5 m)
For the major part of the project area, the absolute height differences
between the two terrain models are less than one meter (light green and dark
green areas). In the street canyon, in the middle of the project area, however,
the absolute height differences are locally more than 5 meters. This is due to
the fact that the height profile of the road prior to execution of the command
was already below terrain. As a result, the biggest local changes in height occur when fitting the terrain to the road‘s geometry.

When using different grid spacings in the interpolation, different results
may occur different.
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Chapter 4 - Topography
4.3.3 Generate Terrain Contours from Height Points
4.3.3
Generate Terrain Contours from Height Points
This software feature enables to generate a new terrain model based on
sparsely distributed height points by using the interpolation provided by the
grid calculation in CadnaA.
Please note the following limitations when using this feature:
•
The subsequent generation of contour lines by grid interpolation
generally reduces the accuracy of the local height information compared
with the initial terrain model from height points.
•
The application of this feature is, therefore, useful only in cases where
there are just few, spatially sparsely distributed height points across the
project area available. In the triangulation, few height information results
in relatively large, flat triangles of constant slope. This means that the
height in these areas is approximative only.
•
For a given sufficiently dense - and perhaps equidistant - grid of height
points it is not recommended to use this feature.

Do not use this feature just because the resulting contour lines can be
interpreted easier visually on the screen or because it may be easier to
„imagine“ the terrain model.
Depending on the settings used for the grid appearance, option „Level
Range“ (see chapter 5.3.2), a more or less fine grid of lines of equal height is
generated. These lines are generated by linear interpolation from the heights
of the existing height points and are displayed as grid contours („Lines of
Equal Sound Level“) is displayed, which are afterwards converted into terrain
contours.
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Procedure
Chapter 4 - Topography
4.3.3 Generate Terrain Contours from Height Points
Initially, there is a file with height points.
4
Terrain model from non-uniformly distributed height points
Proceed as follows:
•
Specify the receiver spacing on the dialog Grid|Specification (in this
example: 10 * 10 m).
At these grid points the terrain height is calculated using the height data of
the height points.

•
The receiver spacing affects the accuracy of the interpolation, since
intermediate values (between the height points) are interpolated
linearly. A very fine spacing is not useful with respect to the resulting
file size, on the other hand, it would fake a higher accuracy of the terrain
model than had the original data.
Select from the list box of parameters on the toolbar of the CadnaA main
window the option „Ground“.
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4.3.3 Generate Terrain Contours from Height Points
4 53
At present, no ground grid existent, the ground grid is empty.
•
Start the grid calculation via the command Calc Grid on the Grid menu.
The ground grid is displayed using the current appearance settings for the
evaluation parameter „Ground“. In addition, in the right corner of the status
bar the ground height is displayed at the location of the mouse pointer („G:
xxx.xx“ m, with G for „Ground“) .
•
By moving the mouse across the grid area, study the value range of
heights on the grid.
•
Open the dialog Grid|Appearance and enter in the dialog range „Level
Range“ the lower and upper limits and the class width of the height range
of the ground grid.
•
Select the display option „Lines of Equal Sound Level“.
In this case, the values for lower and upper limit and for class width
represent heights (in meters) and not sound levels. Thus, the isolines are lines
of equal height.
•
Select a suitable color palette (see chapter 12.6.1) .
Please note that the color palette selected for the evaluation parameter
„Ground“ is not relevant when generating the contour lines. Always the values for „Level Range“ are used - even if disabled.
In order to display the interpolated ground heights at the grid points proceed
as follows:
•
If necessary, reopen dialog Grid|Appearance.
•
Select for „Grid Points“ the option „Values.
After closing the dialog with OK, the ground heights at the grid points are
displayed. If necessary, change the scale using the zoom tool to be able to
read the values.
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Chapter 4 - Topography
4.3.3 Generate Terrain Contours from Height Points
4
Ground grid with lines of equal height having a vertical difference of 1 m
(display range: lower/upper limit: 80/120 m, class width: 1 m)
Height points with interpolated grid of the ground height
showing the ground height in m at grid points (10x10 m spacing)
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4.3.3 Generate Terrain Contours from Height Points
4 55
Now, the contour lines are then generated from the displayed grid lines:
•
To this end, press the key combination ALT+F12.
4
•
Confirm the prompt with OK.
The lines of equal height are converted to the object type „Contour Line“.
•
Select on dialog Grid|Appearnce the option „No Grid“ to no longer
display the grid.
•
Disable the height points to just display the contour lines.
New terrain model based on contour lines
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Chapter 4 - Topography
4.3.3 Generate Terrain Contours from Height Points
When generating the lines of equal height the height at the corners of the
limits (see chapter 9.1) is considered as well. This means that the resulting
heights near the corners of the interpolated area are possibly not valid
because there is no valid height at those points (e.g. too few height points).
Therefore, if necessary, the contour lines generated in these areas need to be
cut or deleted.
In the above example this applies to the north-west corner of the limits (upper left corner). In the corner area there are no height points. Consequently,
the resulting height in this area is defined by the distance and the height of
the corners of the limits (option „Standard Height“, see chapter 6.2.6). The
triangulation ranges from the limit‘s corners to the nearest height defining
object. This means that the height in this area is at random and therefore not
relevant.
Enter a closed polygon that delimits the project area to get deleted from the
one not to be deleted. Select from the context menu of that polygon the
command Break Lines (see chapter 11.25 in the manual „Introduction to
CadnaA“) in order to cut the terrain contours. By selecting the command
Modify Objects from the context menu of that polygon the contour lines
outside can be deleted.
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Chapter 4 - Topography
4.3.4 Generate a Grid of Height Points from Terrain Contours
4.3.4
Generate a Grid of Height Points from
Terrain Contours
This software feature enables to convert a terrain model made from a
contour lines into a grid of equidistant height points. Depending on the spacing of height points, the terrain model can be simplified and reduced in size
(regarding the RAM required).
Application
4
Note again that the procedure described in the following may not be useful
and functional in any case. The decision on the application is with the user.
Initially, there is a file with contour lines.
Terrain model from contour lines:
The area in the upper right corner is supposed to be invalid
since the triangulation occurs from the last contour line to the
limit‘s corner (considering the local height at the corner).
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Chapter 4 - Topography
4.3.4 Generate a Grid of Height Points from Terrain Contours
Proceed as follows:
4
•
Open the CadnaA file with the terrain model based on contour lines.
•
Recalculate the limits wrap-around (via menu Options|Limits, „New“)
•
Close the dialog Limits by OK.

The recalculation of the limits intends to restrict the project area to the
area of the contour lines. Since the terrain is triangulated including the
limit‘s corners, the terrain height outside the area covered by contour
lines is usually invalid. Consider that despite the recalculation of the limits, there may still exist „invalid“ areas, especially with terrain models
having an irregular boundary.
•
Select the point source from the toolbox and place it at the lower left corner of the terrain model.
•
Double-click the point source and click the „Geometry“ button.
•
Enter the x and y coordinates.

•
In order to generate an equidistant grid of height points, it is
recommended to enter integer values. Of course, this is not mandatory.
Enter still a relative height of zero and check that the option „Calculate
from DTM“ is selected.
Point geometry with (x, y, z) = (5, 5, 0) m
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Chapter 4 - Topography
4.3.4 Generate a Grid of Height Points from Terrain Contours
•
Close both dialogs with OK.
•
Select from the context menu of the point source the command
Duplicate.
•
Calculate from the side lengths of the limits and the intended distance of
height points the number of points in x and y directions.
Example: The limits have side lengths of 4 km by 4 km. With a spacing
between points of 10 m, this results in 4000/10 = 400 points in each
direction (including the original point source).
•
Enter on the Duplicate dialog the calculated number of points and the
distance between the centers.
Dialog Duplicate
•
Select from the context menu of a contour the command 3D-Special to
update the terrain heights in the geometry of the point sources.
•
Open the dialog Geometry of a point source to check for the actual
ground height.
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Chapter 4 - Topography
4.3.4 Generate a Grid of Height Points from Terrain Contours
4
Example: The ground height calculated from
the terrain model at this point is 192 m.
•
Click with the right mouse button in an empty area of the screen (or
into the gray area outside of the limits).
•
Select the action "Convert to" for the object typ "Point Source" and click
OK.
•
Select the following dialog Convert Objects the target object type
„Height Point“.
Dialog Convert Objects, here to height points
•
Click OK and confirm with "All".
Subsequently, the point sources are converted to height points while
maintaining their geometry data. The height of the height points results from
the sum (ground height + relative height) of the point sources. Since the relative heights are zero, the z height of the height points correspond to the
height calculated from the terrain model of contour lines.
•
Disable or delete the contour lines via the dialog Modify Objects.
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4.3.4 Generate a Grid of Height Points from Terrain Contours
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4
Example: terrain model with contour lines and height points,
spacing of points (10 by 10) m (before deactivating/deleting the contour lines)
Example: A terrain model from height points having a spacing of 10 m by 10 m.
The terrain profile in the foreground is a result of the triangulation
to the limit‘s corners and must, therefore, be regarded as invalid.
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4.3.5 Generate Cluster of Heights Points from Bitmap
4.3.5
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Generate Cluster of Heights Points from Bitmap
When terrain height data is provided using a (geo-referenced) gray-scale bitmap ("GeoTIFF"), this data can be converted into clusters of height points.
The gray-scale bitmap may have a resolution of up to 16 bit.

Gray-scale bitmap with a resolution of 8 bits can represent 28 = 256
steps in height only!

Colored bitmaps can not be used with this feature.
•
Load the bitmap using the specific functions for the import of bitmaps
(see chapter 10.1 "Insert Bitmaps").
•
Click with the right mouse button into the white area of the CadnaA
main window and select the command Modify Objects from the context
menu.
•
Select the action „Convert to“ for the object „Bitmap“ and click OK.
•
On the dialog Convert to just the target object type „Contour Line“ is
available.
•
Confirm the prompt with OK.
The bitmap is converted into contour lines being clusters of height points
(see chapter 4.1.2 "Height Point", section "Use Contour line as Cluster of
Height Points").
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Chapter 5 - Immissions
For the calculation and the evaluation of receiver levels the following objects
are available in CadnaA:
•
receiver point (see chapter 5.1),
•
area of designated land use (see chapter 5.2),
•
calculation area or horizontal grid (see chapter 5.3),
•
vertical grid (see chapter 5.3.6),
•
building evaluation (see chapter 5.4).
Furthermore, this chapter explains the evaluation features available within the
CadnaA-option XL (see Chapter 15 - Options X & XL).
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5.1 Receiver
5.1
53
Receiver
Receiver points are distinct locations where the sound level is calculated. The
level calculation for receivers is started either via the command Calc on the
Calculation menu or by clicking the pocket calculator symbol
toolbar.
on the
After calculation select the respective evaluation parameter from the list box
on the toolbar top display the results in the graphics.
Compared to grid calculations (see chapter 5.3) the partial levels are stored
for all receiver points. Moreover, a detailed calculation protocol can be produced for receiver points showing all relevant intermediate values (see chapter 6.5 Calculation Protocol).
For receivers, the acoustic rays can be displayed up to the selected order of
reflection provided the option „Generate Rays“ has been activated on the dialog Receiver prior to the calculation.
Dialog Receiver
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Land Use/Standard
Value
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5.1 Receiver
When a limiting level or standard level is specified on the dialog Receiver (either by selection of a type of land use or entering values) it can be evaluated
after a calculation right from the graphics whether this level has been respected or exceeded. In case of excess the receiver point is displayed in red on the
graphics.

5
The color being used for receivers can alternatively be defined via dialog
Appearance using a formula.
Specifying Limiting
Values
Limiting levels or standard levels can be specified in two ways.
Option "Land Use"
By default, the option "Determine from Areas of Land Use" is activated. In
this case, the limiting or standard levels result from the type of land use and
the selected type of noise ("Use Standard Levels for"). The types of land use
are defined on the menu Options|Land Use (see chapter 5.2.1).
When the option "Determine from Areas of Land Use" is deactivated a type
of land use can be selected locally. After calculation, the respective limiting or
standard level is displayed.
Option "Standard Value"
When this option is selected a limiting or standard value for each evaluation
parameter can be entered directly.
Sound Pressure Level
Here the receiver level for each evaluation parameter specified is displayed
(see chapter 6.2.5). Either the selection „Type“ or the input for „Name“ is
used as a designation depending whether option „Name“ has been activated
or not.
Excess Level
Here the excess level value for each evaluation parameter is displayed.
Per default, the receiver symbol in the graphics changes to red if the limiting
value is exceeded for the selected evaluation parameter. Alternatively, a
different color may be used in a formula (see chapter 9.5).
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5.1 Receiver
If this option is activated prior to the calculation at receivers the sound rays
up to the selected order of reflection are displayed using auxiliary polygons
(see also chapter 6.1.7 "Displaying Sound Rays"). The ID of the auxiliary
polygons shows the partial level for the first evaluation parameter and the reflection order.

Option "Generate
Rays (as Aux. Polygons)"
In case the first evaluation parameter is a mixed level (e.g. Lden) the displayed of Ld in the ray/s is enforced.
5
The rays are deleted after having deactivated this option and recalculation.
components of the polygon’s ID:
• RAY: identification as a ray
• 660: partial level Day 66.0 dB(A)
• 00: direct path (0th order)
components of the polygon’s ID:
• RAY: identification as a ray
• 414: partial level Day 41.4 dB(A)
• 01S: ray 1st order, S: screened (i.e. ray is
diffracted by at least one obstacle)
This button appears only when a calculation protocol was generated (see
chapter 6.5). The subsequent dialog Protocol shows the calculation results
per ray. In case the option „Minimum Value for Lr“ is activated (see chapter
6.4), this will be ignored here.
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button „Protocol“
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5.1 Receiver

Level Spectrum (dB)
5
Since the rays are auxiliary polygons they are not shown on 3D-Special
view by default (see chapter 9.5.8). Activate the option „Show in 3D“
on the „3D“ tab of the object type „Aux. Polygon“ (see chapter 9.5) to
display them.
When the emission of sources is specified by spectra the dialog Receiver gets
expanded in order to display the resulting octave level spectrum for the selected evaluation parameters.
dialog Receiver
(type: spectrum in octave bands)
dialog Receiver
(type: spectrum in octave and
third-octave bands)
Note the following remarks regarding the displayed octave or third-octave
level spectrum/spectra:
•
The displayed A-weighted receiver level/s contains the partial levels of all
emission types: those of the sources with A-weighted emission, as well as
those with an emission spectrum in octaves or in third-octaves bands.
•
The octave level spectrum/spectra displayed contains the partial levels of
all sources with an emission spectrum in octaves or in third-octaves.
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5.1 Receiver
•
The third-octave level spectrum/spectra displayed contains the partial
levels of the sources with an emission spectrum in thirds-octaves only.
(see also table below)
emission type
source
... is included in ...
A-weighted
receiver level
spectrum in
octave bands
spectrum in
third-octave
bands
A-weighted
emission
+
-
-
emission in
octave bands
+
+
-
emission in
third-octave bands
+
+
+
•
When a level in an octave band of a single active source is missing, this
frequency band will not be displayed on table "Level Spectrum".
•
The weighting for octave bands can be specified via menu
Options|Miscellaneous (see chapter 6.7).
5
see chapter 4.2
Button „Geometry“
Clicking this button displays the A-weighted partial levels or the octave level
spectra of all sources contributing to the level at this specific receiver in the
table Partial Level (see chapter 5.1.2).
Button "Partial Level"

Partial levels are not displayed in third-octave bands, even when such
sources are present and activated.

In addition, the table Partial Level on the Tables menu shows all Aweighted partial levels for all receiver points.
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5.1 Receiver
Button "AzB-Level"
This button is available with option FLG only.
Entering receivers at
a building’s facade
In order to enter receivers at a distinct distance from a building’s facade, select the command Object Snap on the menu Options (see chapter 9.3).
The default distance is 0,05 m.
The generate receiver points for multiple storeys use the command Generate
Floors (see chapter 11.18 in manual „Introduction to CadnaA“).
5
Specifying the
Precision of Levels
By default, the receiver levels are displayed with a precision of one decimal.
This can be changed via the CadnaA INI-file. Proceed as follows:
•
Close all CadnaA-main windows.
•
Open the file CADNAA.INI and enter in section [Main] the following
text line: dBOutPrec=X (with X: number of decimals).

Regarding the location of the CadnaA INI-file see chapter 2.1 "Installing CadnaA" in the manual „Introduction to CadnaA“.
This setting is relevant for dialog Receiver and for the table Partial Level.
Dialog Receiver: Level with a precision of 2 decimals
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5.1.1 Consistency Check
5.1.1
59
Consistency Check
Prior to the calculation of noise levels at receivers and/or prior to the grid
calculation several input data is checked for consistency automatically. The
consistency check includes:
•
at receivers: object inside a building
•
at point, line, and area sources: object inside a building
•
at point, line, and area sources: no emission value
The objects type and its name are displayed on the dialog Consistency
Check.
Result of a Consistency Check: Point Sources inside Buildings
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5.1.1 Consistency Check
Dialog Options
5
Highlighting an Object
By a single mouse click into a line of the table the respective object is highlighted in the graphics.
Editing of Objects
For editing double-click in a line of the list. This opens the respective object
dialog. Alternatively, marking of a line can and clicking the button "Edit"
opens the dialog as well.
Synchronize Graphic
Clicking this button centers the selected object on the screen. Alternatively,
click into a line while holding the SHIFT-key depressed.
Button "Continue"
continues with the calculation
Button "Cancel"
terminates the calculation
Attribute
CONS_CHECK
This attribute is set (CONS_CHECK= 1) for all objects been displayed or indexed within the consistency check upon calculation. If not indexed CONS_CHECK = 0.
Subsequently, this attribute can be used - for example - to deactivate the objects being displayed within the consistency check:
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5.1.2 Partial Levels
5.1.2
Partial Levels
Clicking the button „Partial Level“ on the dialog Receiver opens the table
Partial Level. With several variants (see chapter 14.2), the partial levels are
displayed just for the variant most recently calculated.
5
List of partial levels at a receiver with all noise sources
and for all evaluation parameters
The list of partial levels displays for the currently selected receiver the Aweighted partial level and the linear or A-, B-, C- or D-weighted octave
spectra for the evaluation parameters defined and for all sound sources
considered in the calculation. The weighting for octave bands can be
specified via menu Options|Miscellaneous (see chapter 6.7).
Partial Level
Receiver
Select the Sort Column (see chapter 11.1.4) command from the context
menu to have the columns sorted by, e.g., partial levels in ascending order.
Double-clicking the cell of the receiver point opens the edit dialog of the
source with this partial level.
Sort Column
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5.1.2 Partial Levels
Overall Partial Levels
Selecting the menu Tables|Partial Levels opens an overall list of the partial
levels at all receiver points caused by all sources considered in the calculation.
Group
On menu Tables|Groups, the partial levels of all noise sources which belong to the group are displayed (see chapter 14.3).
Variants
In case several variants (see chapter 14.2) are defined and active, the partial
levels are displayed for the variant most recently calculated only.
Performance
Parameters with no
Partial Levels
For the following evaluation parameters no partial levels are displayed
(neither on table Partial Level for a receiver, nor on table via Tables|
Partial Level menu):
Suppress Display of
empty Table Lines
•
standard deviations Sigma D/E/N
•
loudest hourly level L1hMaxD/E/N
•
equation =f(x)
The display of "empty" lines in the table Partial Level can be suppressed by
a corresponding entry in the file CADNAA.INI. Add in section [Main] the
following line to achieve this:
NoEmptyPartLev=1
With that value being 1 no „empty“ spectra will be displayed.

„Empty“ spectra result from sources outside of the search radius or
from sources been excluded from the calculation due to a maximum
error specified.

Irrespective of this setting, the partial levels of all sources will be
displayed on dialog ObjectTree|Partial Level and on table Partial
Level on the Tables menu.
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5.2 Area of Designated Land Use
5.2
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Area of Designated Land Use
Areas of different land use allow for the description of the designated land
use in accordance with the Land Use Ordinance. Points within such areas can
thus be assigned the standard levels for the different types of noise (menu
Options|Land Use). This feature allows you to adopt the types of
designated land use for the entire CadnaA project directly from development
plans, and to calculate sensitivity maps. This leads to conflicting maps where
the differences between the rating levels calculated for each type of noise and
the standard levels, as per the designated land use, are calculated (requires
option X or XL).
CadnaA can also automatically assign the pertinent standard levels to all receiver points lying within a defined area of land use. The prerequisites are
1.
that the check box „Determine from Areas of Land Use“ is activated in
the edit dialog of the receiver point and
2.
an area of designated land use is inserted in which the receiver points
are included.
Enter the borderlines of the areas of designated land use after clicking the
icon on tool box.
In the edit mode double-click the borderline of the inserted area and select
the type of land use from the list box.
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5.2 Area of Designated Land Use
Population /
km²
(requires X or XL option) - The menu command Grid|Population Density
allows CadnaA to approximate the population density from the buildings,
and to assign it to the areas of designated land use (see chapter 15.4).
Monetary Data
(requires X or XL option) - A technique to evaluate the noise is described in
the Swiss BUWAL study /88/. This method is implemented in CadnaA (see
chapter 15.5).
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5.2.1 Type of Land Use
5.2.1
Type of Land Use
Via the menu Options|Land Use, the standard levels for the defined evaluation parameters (see chapter 6.2.5) applying to the different types of noise
and the appearance - filling pattern and color - are assigned to the different
types of land use. These different kinds of land use can be selected in the edit
dialog of the object Area of Designated Land Use (see chapter 5.2).
5
Via this dialog new types of land use areas can be defined.
•
Select a blank line in the Land Use table. Just click the white area.
•
Then enter a name and the pertinent standard levels in the boxes.
By default, the first item on the list of land uses is reserved for the type
„(ohne Nutzung)“ (i.e. „without/no use“). The position of this first item
shall no be altered for reason of correct assignment.
Land Use „(ohne
Nutzung)“
Colors, line style, and filling pattern for representation of the area can then be
selected as customary after clicking the color button.
Colors, Line Style, and
Fill
In practical work it will be useful to switch off the filling pattern of areas with
a certain land use for the clarity of the colored noise maps.
User-defined types of land use are saved with the project. They are not available for other projects.
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5.3 Receiver Grid
5.3
Receiver Grid
On the menu Grid the following features are available:
•
specifying the spacing and the height of grid points (see chapter 5.3.1),
•
launching grid calculations (see chapter 5.3.3) for up to 16 variants (see
chapter 14.2) and for up to four evaluation parameters (plus the ground
grid, see chapter 6.2.5),
•
selecting the type of appearance of the grid/noise map (e.g. as lines or
areas of equal sound levels, see chapter 5.3.2),
•
commands to open, save, delete, compress/decompress and to resample
grids.
5
The grid calculation for the specified evaluation parameters and the defined
grid spacing is launched by the command Calc Grid (see chapter 5.3.3).
Calc Grid
Selects the grid for the corresponding evaluation parameter from the list box
on the toolbar on the CadnaA main dialog.
Select Evaluation
Parameter
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5.3 Receiver Grid
Grid|Open
With the command Grid|Open a saved grid can be loaded into the present
file. Select the corresponding file via the dialog. Using multiple selections
several grid files can be loaded at once. A grid cannot be loaded via the
command File|Import.
different Evaluation
Parameters
In case a grid file contains several grids with different evaluation parameters
they will only be displayed if the same evaluation parameters also exist in the
current file.
Grid Formats
Following grid formats can be opened:
•
•
•
•
•
•
•
•
option „Keep Current
Grid“
CadnaA-grid (*.cnr) and CadnaA-files (*.cna)
ESRI ASCII-grid (*.asc, *.hdr, *.flt): Both, non-proprietary ASCII raster
files (*. asc) as well as proprietary binary raster files (*.hdr, *.flt) are
imported.
ASCII-grid (*.rst)
LimA grid (*.ert)
SoundPLAN grid (rlk_.*;*.gm)
Immi grid (*.ird)
AUSTAL grid (*.dmna)
NMGF grid (*.grd, from NMPlot, TNM, INM)
When the option „Keep Current Grid“ is activated you can load grids in the
current file without deleting the existing ones. The first existing calculated
grid in the current file sets the mash of the grid. With different grid spacings
of the present and the loaded grids, the resulting grid will be adjusted to the
original by interpolation.
This function enables the calculation of a large file using several calculation
areas on different computers sharing the file by calculating only one of the
calculation areas one after the other. Afterwards all the grids will be merged
into the original file via command Grid|Load with the option „Keep
Current Grid“ activated (see chapter 6.10 "PCSP - Program Controlled Segmented Processing").
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5.3 Receiver Grid
With the command Grid|Save as only the calculated grids will be saved, so
not the object data. The following file formats are available:
•
•
•
•
Save Grid as
CadnaA-Grids (*.cnr)
ASCII-Grids (*.rst)
LimA Grids (*.ert) and
NMGF Grids (*.grd).
When saving to an ASCII grid the evaluation parameters as entered or edited
will be used as a designation (see dialog Configuration, Evaluation Parameters Tab).
5
Furthermore, grid data can be exported as lines or areas or as an ASCII file
for ArcView (see chapter 13.3.2 "ArcView (*.shp)").
Text file with ASCII-grid data for 4 evaluation parameters (format *.rst)
By the command Grid|Delete the existing grid (for up to four evaluation parameters, plus the ground grid) is deleted and from the file (upon Save). This
command cannot be undone.
Grid|Delete
When deleting a grid, the settings for the grid spacing and for the grid
appearance are kept. However, when selecting the command Grid|Delete
while keeping the SHIFT key depressed restores the default settings for grid
spacing and grid appearance.
Selecting the command Grid|Delete while keeping the CTRL key depressed
will delete - after having confirmed a prompt - all grids in all variants.
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Grid|Compress,
Decompress
Chapter 5 - Immissions
5.3 Receiver Grid
By the command Compress on the Grid menu grids resulting from former
CadnaA releases can be compressed in order to reduce their volume. By contrast, the raster data from files created with CadnaA release 4.3 or later will
be compressed automatically upon calculation.
The command Decompress enables to decompress the raster data resulting
from releases starting from 4.3. Decompressing grids is required when grids
having different calculation areas shall be combined (see chapter 5.3.4 "Grid
Arithmetic").
5
Additional Information
The background of these two commands is the requirement to further reduce
the disk space required for large-scale grids, in particular. This is advantageous when loading, storing and calculating grids.
In CadnaA, prior to release 4.3, the grid area saved at tilted calculation areas
was given by the smallest enveloping rectangle. In fact, the grid area always
represented a rectangular section within the limits whose edges were parallel
to the coordinate axes xy.
Starting from CadnaA release 4.3 just those grid points are saved which are
distinctively located inside the calculation area(s), thus causing a compression
of the grid when being saved.
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5.3 Receiver Grid
The example below shows a tilted calculation area. When saving the grid with
a release version prior to 4.3 all the points within the left red rectangle have
been saved. This also comprises the grid points which are located outside the
calculation area.
Example
In contrary, the right red rectangle delimits the grid area, which is stored
starting from release 4.3. This area corresponds to the calculation area.
5
Saving of Grid Data prior to release 4.3
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Grid|Resample
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5.3 Receiver Grid
The command Resample offers to interpolate a grid with a given receiver
spacing into a new grid with a different receiver spacing.
Dialog Resample Grid
On the dialog Resample Grid enter the new receiver spacings dx and dy. After clicking OK, the resampling is processed.
Resampling is possible starting from a coarser grid (larger receiver spacing) to
a finer grid, but also starting from a finer grid (smaller receiver spacing) to a
coarser one.
Note that in particular when resampling a coarser to a finer grid the intermediate grid points are generated using linear interpolation. Moreover, by „upsampling“ and then “down-sampling“ - obviously - the initial grid cannot
not be regained.
Application
Resampling may be used in conjunction with grid arithmetics (see chapter
5.3.4) when rearranging several input grids with different receiver spacings to
a common resulting grid.
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5.3 Receiver Grid
(displaying the grid points as dots)
Example
initial grid
(10 x 10) m
5
initial grid
resampled to
(2.5 x 2.5) m
receiver spacing
initial grid
resampled to
(50 x 50) m
receiver spacing
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5.3 Receiver Grid
resampled grid
(50 x 50) m
again resampled to
(2.5 x 2.5) m
receiver spacing
5
The valid grid size has
reduced because - due to
the resampling to (50 x 50)
m spacing - a part of the
grid no longer exists (i.e.
lying outside the
calculation area).
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5.3.1 Grid Specification
5.3.1
Grid Specification
On this dialog the distance between grid points in x and y direction and the
receiver height in meters is specified. By default, a spacing of dx=dx=10 m
and a receiver height of 4 m is used.
Grid Spacing and Height
A smaller grid spacing results in a higher density of grid points which
enhances the contours in the graphics of the lines or areas of equal sound
level. On the other hand, a finer grid requires more calculation time.
By default, the grid height is relative with respect to the ground level. In order
to calculate using an absolute grid height, activate this option. In this case, the
grid does not follow the terrain’s shape. This will case that grid points below
terrain are ignored in the calculation.
5
absolute Grid Height
Dialog Receiver Grid with optional features
Both options are activated by default. In this case, no grid points are placed
into the horizontal projections of sound sources and buildings. Consequently,
no level is calculated at those grid points.
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Option „Exclude Sound
Sources/Buildings“
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5.3.1 Grid Specification
Option „Use Height of
Buildings“
By activating this option in addition to the option „Exclude Buildings“, the
horizontal projection of a building is excluded from the grid if the building
height exceeds the grid’s height. By default, this option is deactivated.
for all Variants
When more than a single variant (see chapter 14.2) is used, this option is activated by default. In this case, all active variants make use of the same grid
spacing.
By deactivating this option for a variant and by entering a different grid
spacing dx|dy, this option gets automatically disabled by CadnaA for all
other active variants. For these variants, however, the grid spacing itself
remains unchanged.
5

In case this option is deactivated (for one or for all variants) and the
grid spacing matches for all active variants, the option is activated by
CadnaA for all variants automatically.
Button „Options“
Option „Define Grid over
entire Limits“
With this option activated the grid covers the entire defined limits of the
project file (see dialog Options|Limits), provided no calculation areas have
been defined.
With this option deactivated, the calculation area can be restricted bey entering the x and y coordinates for the bottom left and the upper right corners of
the grid. Alternatively, a calculation area can be used to restrict the grid’s
area (see chapter 6.4 "Selecting Data for the Calculation").
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5.3.1 Grid Specification
In this example, building 1 has a height of 10 meters and building 2, a height
of 3 m. The grid’s height is at 4 m.
Example
•
Load the addressed file.
 Examples\
•
Activate on dialog Receiver Grid the options „Exclude Buildings“ and
„Use Height of Building“.
•
Set on the dialog Options|Appearance the fill of the buildings to
„transparent“.
•
In order to achieve this, select any type of hatching first and make sure
that the option „transparent“ is activated.
•
Deactivate on dialog Calculation|Configuration, „General“ tab, the
option „Extrapolate Grid ’under’ Buildings“. This will prevent the lines
are the areas of equal level to reach to the inside of the building’s borders.
•
Start the grid calculation (e.g. for a grid spacing of 1 by 1 m).
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5.3.1 Grid Specification
The following graphic results:
5
Grid after calculation at a height of 4 m
with activated option „Use Height of Buildings“,
building 2 is covered by the grid’s lines of equal sound level
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5.3.1 Grid Specification
The command Delete Grid Points from the context menu of a calculation
area is useful to „cut out“ calculated noise maps either to replace that portion
after a new calculation or to use only a section of a big noise map. The PCmemory used for the deleted section of the grid will be released.
Delete Grid Points
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total grid area
(white framed area: calculation area
inside the present grid area
By selecting the command from the context
menu of the inner calculation
area the grid points inside are deleted.
recalculated grid using LmE,D/N+ 3 dB
in the inner calculation area
total grid imported by Grid Open with
option „Keep Current Grid“ activated
Insert an arbitrarily shaped calculation area over a calculated noise map, highlight the polygon and select Delete Grid Points from the context menu. Select either inside or outside the polygon. The settings of the current grid will
be assigned to the imported grid.
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Grid Appearance
Via the dialog Appearance on the Grid menu the settings for displaying grid
results are defined. The dialog comprises of the following sections:
•
•
•

section „Show“: selection of display mode
section „Color Palettes“: selection of color palettes, globally for all evaluation parameters or individually for each evaluation parameter.
Level Range and Line Width: This section corresponds with the options
available in former releases of CadnaA. The display options resulting
from former CadnaA files will be displayed for color palette „(file)“.
When using color palettes, it is recommended to deactivate the option
„Level Range“.
Dialog Grid Appearance
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Button „Apply“
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5.3.2 Grid Appearance
When clicking the button „Apply“ the modifications are applied to the main
window immediately while keeping the dialog open.
Show ...
Lines of Equal Sound
Level
With this option the lines of equal sound level are displayed on the grid. The
value range and the class width (and all further settings) result from the select
color palette/s. The grid caption results from the specification for „Single
Value“ of the selected color palette (see chapter 12.4 "Symbol Library").
Areas of Equal Sound
Level
With this option the areas of equal sound level are displayed on the grid. The
value range and the class width (and all further settings) result from the selected color palette/s. The grid caption results from the specification for „Interval“ of the selected color palette (see chapter 12.4 "Symbol Library").
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In either case, the boundaries are interpolated (by linear interpolation). With
the option „Exclude Sound Sources/Buildings“ (see chapter 5.3.1 "Grid
Specification") activated, uncolored areas in the vicinity of buildings or area
sources may result, depending on the spacing of receiver point. In order to
avoid this, the option „Extrapolate Grid under Buildings“ on menu
Calculation|Configuration is activated by default (see chapter 6.2.2 "General Tab"). In this case, the colored areas of the grid start from the object’s
boundaries.
Raster, Oversampling
When the oversampling is set to 1 (default value) the representation applies
the resolution of the specified receiver spacing (see chapter 5.3.1 "Grid Specification"). With an oversampling of larger than 1 intermediate grid points are
generated additionally. The sound level at those intermediate points is determined by linear interpolation.
No Grid
With this option no noise map is displayed on the graphics (2D-view).
Nevertheless, on the 3D-Special view the colored grid is still displayed. To
avoid this, switch to the option „Ground“ from the list box on the toolbar of
the main dialog. This will cause the no grid being displayed on the 3D-Special view.
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5.3.2 Grid Appearance
On the dialog section „Color Palettes“ the color palettes for up to four
evaluation parameters and for the ground grid are selected. With the default
setting, the color palette selected for evaluation parameter 1 is applied to all
further evaluation parameters and the ground grid. To select a color palette
for each evaluation parameter and the ground grid activate the respective
check box.
Color Palettes
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Dialog Grid Appearance, section „Color Palettes“
By default, the color palette „(default)“ is preselected for all grids. The default
color palette corresponds with the formerly used grid appearance settings,
with respect to the type of grid shown (Raster, Oversampling 1) and the level
range.
Color Palette „default“
When loading a file which has been generated using a former version of
CadnaA the settings on dialog Grid Appearance will be displayed for the
color palette „(file)“. The color palette „(file)“ is stored in the local library of
color palettes (see chapter 12.6).
Color Palette „file“
After activation of the check box, color palettes from the local library can be
selected from the list box for each evaluation parameter. The text displayed
on the list box is the ID-code of the respective color palette in the local library.
Selecting Color Palettes
Color palettes from the global library are selected by clicking the file selection
symbol. SHIFT-clicking on the file selection symbol opens the local library of
color palettes.
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Examples
The palette „pal_35_85_step_5“ is
used for all four evaluation parameters (if any) and the ground grid.
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The palette „pal_35_85_step_5“ is
used for evaluation parameters 1, 2, 4
and for the ground grid.
For evaluation parameter 3 the palette „pal_0_20_step_2“ is used.
Compared to the last setting, now the
default color palette is used for the
second evaluation parameter.
For evaluation parameter 3 and for
the ground grid the palette
„pal_35_85_step_5“ is still used.
When loading a file from a former
release of CadnaA, the color palette
„(file)“ resulting from this file is used
for all evaluation parameters and for
the ground grid.
REMARK: In this case, the grid
appearance corresponds with the
appearance in former CadnaAreleases.
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5.3.2 Grid Appearance
This option may have three modes: deactivated (no tick mark), activated
(black tick mark), neutral (grey tick mark). In the neutral mode (default setting) the setting for „Progressive Color“ of the respective color palette applies. Thus, if a progressive color has been defined in the color palette it will
be used, and vice versa. With this option deactivated, color palettes with progressive colors show use distinct color with transition. With this option activated, color palettes without progressive colors show them, instead.
Progressive Colors
The option „Grid Points“ enables to mark the locations on the grid where
the level has been calculated (selection „Dots“) or of the calculated levels at
those locations (selection „Values“).
Grid Points
When displaying the terrain’s height (see chapter 4.5) the height in meters is
displayed with the option „Values“ selected. The same holds for attribute values resulting from ObjectScan (see chapter 15.1).
When loading a file created by a former release of CadnaA, the dialog Grid
Appearance displays the grid settings for the color palette „(file)“. The lines
and areas of equal sound level include - as it was the case with former releases
of CadnaA - the upper limit of every value range (i.e the option „Interval
Border to Lower Interval (lo < xxx <= hi)“ is activated, see chapter 12.6
"Color Palettes").
Level Range
The value in this box will just have an effect if either the option „Lines of
Equal Sound Level“ or „Areas of Equal Sound Level“ is activated. The class
width defines the width between adjacent lines of equal sound level.
Class Width
The lower and upper limits define the level range.
Lower/Upper Limit

The option „Level Range“ should nowadays not be used when defining
the grid appearance as it disables the selected color palettes.
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5.3.2 Grid Appearance
The grid captions as being defined can be inserted into the graphics and be
printed via the Plot-Designer by use of the object „Symbol“ (see chapter
9.11.3 "Symbol" and chapter 13.1.2 "PlotDesigner - Cell Types"). Furthermore, a grid caption can be added even to the 3D-Special view (see chapter
9.14.1,).
Line Width
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Provided the display mode „Lines of Equal Sound Level“ is selected, noise
contours can be highlighted by thicker lines in intervals. For example, in order to draw a thicker line in steps of 10 dB, activate the first option „Line
Width“ and select „??0.0" from the list box. Here, the question marks serve
as wild cards for any other figure. In order to draw a thicker line in steps of
5 dB in addition, activate the second option „Line Width“ and select „??5.0"
from the list box. The line widths are specified in tenths of millimeters (mm/
10).

Import of old PaletteFiles
As already with the level range, the option „Line Width“ is only used to
display grid appearance settings resulting from former CadnaA files.
Nowadays, the definition of the line width for each value range is part
of the color palette.
The button „Import old Palette-File“ enables to load files with color palettes
(file extension *.PAL) from former CadnaA releases. The imported color
palette is shown on the list box for the evaluation parameter 1 and simultaneously copied to the local library.
This feature can be used to import an arbitrary number of existing color palettes to the local library by multiple import.
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5.3.2 Grid Appearance
This option is enabled by default. In this case, the same settings for the grid
appearance are used for all active variants (see chapter 14.2).
Option „for all
Variants“
By deactivating this option for a distinct variant - after this variant been
selected - and specifying a different grid appearance for this variant, this
option is automatically deactivated by CadnaA for all other active variants.
For these variants, however, the current grid appearance settings are not
changed.

In case this option is deactivated (for one or for all variants) and the
grid appearance settings match for all active variants, the option is
activated by CadnaA for all variants automatically.
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5.3.3 Grid Calculation
5.3.3
Grid Calculation
The command Calc Grid in the Grid menu launches the grid calculation.
With more than a single variant active, the following dialog is displayed enabling to select variants:
5
Dialog Calculation (via command Calc Grid on Grid menu)
In this case, the grid of the active variant or the grids of all variants or a
selection of variants can be calculated.
With lasting grid calculations the following, estimated time intervals,
estimated based on the calculation progress and the project size, are displayed
on the progress dialog:
•
the elapsed time interval (format hh:mm:ss) and
•
remaining time interval for the calculation (format hh:mm:ss).
If no calculation area has been defined (see chapter 6.4 "Selecting Data for
the Calculation") the calculation is performed within the entire limits (see
Options|Limits menu). Otherwise, only the active calculation areas will be
calculated.
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5.3.3 Grid Calculation
The grid calculation takes into account all objects and sound sources, even if
they lie outside the specified calculation area (see also Check Consistency
chapter 5.1.1).
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Update during
Grid Calculation
With the activated option „Update during Grid Calculation“ (menu
Options|Miscellaneous) the calculated grid is built up by colored areas
while the calculation is still in progress.
Canceling/Interrupting
the Grid Calculation
A grid calculation may be stopped, or interrupted to be resumed later on, at
exactly the point where it was stopped. Click the „Stop“ button and wait until
CadnaA has interrupted the calculation.
Resuming a Grid
Calculation
In order to later relaunch a canceled grid calculation, first save the project file.
CadnaA will save with this the progress status of the grid calculation. Select
the command Grid|Calculate Grid. while holding the SHIFT key depressed
to resume the grid calculation.
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5.3.4 Grid Arithmetic
5.3.4
Grid Arithmetic
The dialog Grid Arithmetics offers to generate new grids from several input
grids, for example, in order to generate the sum or the difference of grids.
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Dialog Options
The current grid is assigned by R0 (or r0). By clicking on the file selector
symbols up to 6 saved grids can be loaded (file formats *.cna or *.cnr).
Use Grid
In these boxes a formula can be entered for each evaluation parameter
defined using the grids R0 and R1 to R6 respecting the rules for expressions
and operators (see Chapter 5 - Operators & Functions in the manual
„Attributes, Variables and Keywords). When clicking OK the new grid is
calculated processing the numerical expression/s.
Expression for new Grid
Example:
•
•
•
grid R1 with obstacles and screening
grid R2 without obstacles
difference grid R2-R1 showing screening effect (Abar) as a grid map
For further examples see the CadnaA-manual „Attributes, Variables, and
Keywords“.
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5.3.4 Grid Arithmetic
Input Boxes for Evaluation
Parameters
The check boxes in front of the four evaluation parameters enable to define
specific expressions for each evaluation parameter. Per default, none of the
check boxes is activated. This causes the expression for the first evaluation
parameter (Ld/Day for evaluation parameter LP1, see chapter 6.2.5) to be
applied to all other evaluation parameters as well. Activate the respective
check box to enter a different expression for this evaluation parameter.
New Grid is Intersection
of Input Grids
When several grids are loaded this option causes to just evaluate and display
the grid area which is an intersection of the input grids (i.e. where the input
grids are overlapping). This option is activated by default.
Grids in Variants
Provided the project file contains several variants these can be assigned as
well - besides the current variant (for table with variables, see section "Grid
Variables for Evaluation Parameters").
Examples
Grid Summation
Enter in the first input box „Expression for New Grid“ the formula r0+1.
Since the check-boxes for the other evaluation parameters are deactivated,
the calculation is applied all evaluation parameters in the same way.

The same effect would occur when activating all check-boxes and
entering into each input box, starting from the first one: r01+1, r02+1,
r03+1 and r04+1.
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5.3.4 Grid Arithmetic
In this example, the current grid (r0) and the loaded grids R_B.CNA and
RK_G.CNA are added energetically. From this sum the loaded grid
RK_STR.CNA are linearly subtracted. By using the settings below the
calculation occurs for all evaluation parameters using the same expression.
Energetic Summation
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In this example, the grid is calculated and saved using a point source in front
of a reflecting barrier. Afterwards this file is loaded to field R1. Now,
deactivate the reflection (by setting the reflection order to zero on tab
„Reflection“ in the configuration, see chapter 6.2.8) and restart the grid calculation.
Calculate the difference by subtracting the current grid (r0) from the loaded
grid R1 using the expression r1-r0. The resulting grid shows the level increase
due to reflection.
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Grid Variables for
Evaluation Parameters
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5.3.4 Grid Arithmetic
In a grid or a grid file up to four evaluation parameters plus a ground grid can
be saved. In case the designation for the variant Vyy is missing the current
variant is evaluated. The distinct grids can be addressed as follows:
R0
refers to the current grid with all defined evaluation
parameters. A grid arithmetics would effect all grids of
all evaluation parameters.
R01 to R04
refers to the current grid, just for one the defined
evaluation parameters 1 to 4
R0g
refers to the current ground grid
R1
refers to a saved grid loaded to input box R1 and effects
the grids of all evaluation parameters
R11 to R14
refers to the grid loaded to input box R1, just for one the
defined evaluation parameters 1 to 4
R1g
refers to the ground grid loaded to input box R1
R3 to R6
analogously as described above
R1V01
refers the grid of all evaluation parameters in variant
V01, loaded to input box R1
R1V011 to R1V014
refers the grid of one of the evaluation parameters 1 to 4
in variant V01, loaded to input box R1
R6V161 to R6V164
refers the grid of one of the evaluation parameters 1 to 4
in variant V16, loaded to input box R1
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NOTE - The reference to a variant must use a doubledigit (RxVyyEvalParaNo or rxvyyEvalParaNo with
x=1..4, yy=01..16, EvalParaNo=1..4).
Combining Grids using
different Calculation
Areas
When combining grids which are using different calculation areas, please
note that CadnaA compresses all grids automatically upon calculation in
order to save disk space. In these cases - especially when grid arithmetics is
displaying odd results - it requires to decompress all grids prior to applying
the grid arithmetics (see chapter 5.3 "Receiver Grid").
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5.3.4 Grid Arithmetic
When several grids are loaded this option causes to just evaluate and display
the grid area which is an intersection of the input grids (i.e. where the input
grids are overlapping). This option is activated by default.
option „New Grid is
Intersection of Input
Grids“
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Grid calculations for
EU-noise indices with
CRTN
Chapter 5 - Immissions
5.3.4 Grid Arithmetic
When applying the English guideline CRTN ("Calculation of Road Traffic
Noise") in conjunction with calculations according to the EC Environmental
Noise Directive /121/ the L10 grid can be converted to a Leq grid according
to method 3 of the TRL-study (/83/) in order to evaluate Lden and Ln.
The entire procedure requires several steps:
1.
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setup for calculation of initial levels LA10,18h for Non-Motorways and
Motorways: In order to calculate LA10,18h select the performance parameters Ld on the tab Performance Parameters (Calculation|
Configuration menu) with CRTN selected as road standard.
Later, the conversion of levels LA10,18h into levels Lden and Ln according to
TRL-study can be performed with both, non-motorways and motorways, in a
single CadnaA-file provided that non-motorways and motorways are addressed to two variants.
2.
Define three variants, for non-motorways, motorways, and for all roads.
Define groups according to IDs being different for non-motorways and
motorways, for example:
As the grid is calculated just for the active variant the grids for nonmotorways and motorways has to be calculated in two steps.
3.
Select variant "non-motorways" and calculate grid. Save this grid via
Grid menu, Save as (e.g. filename "non_motorways.cnr").
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4.
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Switch to variant "motorways" and calculate grid.
Next, the two grids for LA10,18h are converted into grids Lden and Ln.
5.
Activate the END-performance parameters 1: Lden and 2: Ln on the dialog Configuration (Calculation menu). Make sure that hours are allocated to the three daily periods D, E, N and penalties are entered.
6.
Convert grids using the following expressions via the dialog Grid
Arithmetic (on Grid menu) for „Expression or a new Grid“ with the
syntax:
crtn_X (LA10,18h_nonmot, LA10,18h_mot)
with the possible evaluation parameters X = (d, e, n, den)
At the first location within the brackets, the L10 grid for "non-motorways" is
referenced (e.g. LA10, 18 h_nonmot). At the second location, the L10 grid for
"motorways" is referenced (e.g. LA10, 18 h_mot). With the specifications as
in a following illustration the grids for Lden and for Ln result in a single step.
In the example above, the present grid is for „motorways“ (R0) while the
loaded grid R1 is the grid for „non-motorways“. The expressions to be
entered are:
for Lden:crtn_den(r11,r01)
for Ln: crtn_n(r11,r01)
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
Please consider that the first grid has to be always the grid for nonmotorways and the second for motorways.
7.
In this example, the result are grid for Lden (1st parameter) and Ln (2nd
parameter). Select variant "all" to activate both types of roads.
Explanatory Remarks:
The TRL-study /83/ lists regression formulas to recalculate Leq for the time periods
Day, Evening, and Night based on statistical evaluations. When just having daily traffic
counts available „Method 3“ of the TRL-study applies.
5
For non-motorway roads: Lday  0.95  LA10,18 h  1.44 dB
(Equation 1)
Levening  0.97  LA10 ,18 h  2.87 dB (Equation 2)
For motorway roads:
Lnight  0.90  LA10 ,18 h  3.77 dB
(Equation 3)
Lday  0.98  LA10 ,18 h  0.09 dB
(Equation 4)
Levening  0.89  LA10 ,18 h
 5.08 dB (Equation 5)
Lnight  0.87  LA10 ,18 h  4.24 dB
(Equation 6)
The above equations will be used in CadnaA when converting the grid for LA10,18h
into the resulting grids for Lden and Ln.
Additional features
for grid conversion
with CRTN
CadnaA offers additional commands for converting LA10,18h into Ld and Le.
The general syntax is:
crtn_x (LA10,18h_nonmot, LA10,18h_mot) where x = (d, e, n, den)
LA10,18h_nonmot: grid for non-motorways
LA10,18h_mot: grid for motorways
This conversion respects the allocation of hours and the entered penalties.
Example 1
The expression:
crtn_den (r01, r11)
converts the parameter 1 for non-motorways in the current grid (r01) and the
parameter 1 for motorways of loaded grid r1 (r11) into Lden-grid.
For evaluation the Lden-grid based on Leq-levels Ld, Le, and Ln the
expression is:
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Lden(day, evening, night)
This conversion respects the allocation of hours and the entered penalties as
well.
Having three grid for Ld, Le, Ln calculated the Lden-grid can be generated as
the 4th grid by entering the following expression:
Example 2
Lden(r01, r02, r03)
converts the parameter 1,2,3 of the current grid (r01, r02, r03) into Lden grid
see also:
chapter 11.2.1 "Editing the Result Table", section "Conversion to EUindices at individual receivers with CRTN / TRL"
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5.3.5 Generating a Grid from Noise Contours
5.3.5
Generating a Grid from Noise Contours
A noise grid can be generated in CadnaA from Iso-dB-lines (noise contours)
using an external file format. In some cases, there will be just Iso-dB-lines
(e.g. aircraft noise contours) available in some external format. In order to
add this information to the already existing grid it requires to generate a grid
using those geometrical lines, representing noise contours (see chapter 5.3.4
"Grid Arithmetic").
5
In a first step, the geometrical lines, representing noise contours, are exported
to DXF format (with activated option „Height is Level“ and deactivated
option „No Grid points“). Now, this exported DXF file is used to generate a
grid from these isolines. To this end, import the DXF file into a new
CadnaA file (thus, avoiding to recalculate the existing grids of evaluation
parameters, if any).
•
Select from File|Import menu the format „AutoCAD DXF“.
•
In the Options dialog import the Iso-dB-lines as contour lines (with
layer name *). Deactivate the auxiliary polygons at the end of the list.
This procedure, however, just works in case the level values are stored as
heights of the terrain contours in the import file.
•
Now, calculate ground grid (its calculated automatically with Grid|Calc
Grid command).
•
Enter class width and an upper and lower limit and specify the grid‘s
receiver spacing (menu Grid|Specification).

•
When calculating the ground grid, no source is required.
Open from the Grid menu the dialog Arithmetics and enter this
expression for new grid: r0g
By this, the grid of ground heights has been converted to a noise grid which
can be saved for further use. To do this select any evaluation parameter from
the toolbar (but not „Ground“ grid) and select command Grid|Save. The
saved grid file can be opened and used for further grid arithmetics (input
boxes R1 to R6).
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5.3.5 Generating a Grid from Noise Contours
When the level information is just available as text (so, not as a numerical
value stored, but e.g. in the ID of the terrain contours) there is a further possibility to extract the value form the string information.
5
Sound level values as text information in the ID,
i.e. the values are not assigned as height
Proceed as described in the following.
 Examples\05_Immissions\Raster_IsodB.cna
•
Change the string in the „ID“ column by applying the context menu command Change Column (see chapter 11.1.3) in a way that just the level
value remains. Using the example above, the following input generated
the desired result.
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expression for Replace Strings
remaining results are just the sound level values
Now, the values in the ID column have to be transferred to the column
„Height, Begin“. Therefore
•
Click with the right mouse key into the white area on the screen and select
the context menu command Modify Object.
•
Select the action „Modify Attribute“ for the object type „Contour Line“
and confirm by OK.
•
On the dialog Modify Attribute select the attribute HA (for height at the
first point) and the option „Arithmetic“, with „New Value“ = ID (you
may select this attribute via the double-arrow key instead).
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5
Settings to insert the sound level value from the ID box into the height column
•
Close the dialog with OK and confirm the subsequent dialog with „All“.
Subsequently, the level values from the ID column are inserted into the
height column.
Now, proceed as described at the begin of this chapter to calculate the
ground grid. In this example a grid spacing of 5 x 5 m has been used.
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Iso-dB lines imported as terrain contour lines
grid generated by using imported terrain contours (appearance: areas of equal sound level)
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5.3.6 Vertical Grid
5.3.6
Vertical Grid
By the object Vertical Grid grid calculations can be performed on vertical
sections resulting in a colored vertical noise map. Vertical grids may be printed, copied or saved and reopened. Furthermore, vertical grids are displayed
on the 3D-special view.
The following example shows a road and two buildings.
Example
5
Select the object Vertical Grid from the toolbox and draw a polygon with
two points determining the location of the vertical grid. An arbitrary number
of vertical grids can be entered. The default height for the vertical grid is 20
m. This height can be modified on the dialog Geometry. Up to this height
the grid calculation is performed.
Vertical noise map up to 50 m height in the 3D-Special View
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Dialog Options
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5.3.6 Vertical Grid
When opening the dialog Vertical Grid the graphics uses the same scale as at
the horizontal grid. By default, also the grid specification (see chapter 5.3.1)
and grid appearance settings (see chapter 5.3.2) of the horizontal grid are applied.
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Dialog Vertical Grid
Option „Global“
With this option activated (default) the settings of the horizontal grid are
used. After deactivation of this option, individual settings of the grid can be
edited using buttons „Specification“ and „Appearance“.
Button „Calculate“,
option „automatically
Clicking the button „Calculate“ starts the calculation of the vertical grid.
During this calculation the dialog remains open. When the option
„automatic“ is activated, the vertical grid will be recalculated each time the
horizontal grid is calculated. This requires to close the dialog first.
Button „Save as“
This button offers to save the vertical grid (file extension *.cnr).
Loading Vertical Grids
Saved vertical grids can be opened using the key combination ALT+o (letter
„o“)
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5.3.6 Vertical Grid
After calculation the sound level at the location of the mouse pointer is displayed in the upper part of the dialog (to the right of „Grid“).
Display of Level
Via this button the graphics is copied to the clipboard and can be inserted
into another application using the key combination CTRL+v.
Button „Copy“
With several active vertical grids in a file, the grids are displayed all together
on the 3D-View (see chapter 9.13) and in the 3D-Special View (see chapter
9.14).
3D-Special View
Via the Properties menu of the 3D-Special view a transparency (%) to the
vertical grid can be defined. This enables to display objects covered by the
vertical grid.
Grid transparency
Vertical grids can be referred to in PlotDesigner. This holds for the 3DSpecial view and laos for sections as shown on dialog Vertical Grid (see
chapter 13.1.3, section "„Plan“ tab").
PlotDesigner
The generation of level difference grids is possible also with vertical grids.
Proceed as follows:
Grid Arithmetics
•
Save the two grids to be subtracted from each other using the button
„Save as“ on the dialog Vertical Grid.
•
Now, load one of the two vertical grids using the command Open on
menu Grid.

A current grid r0 is required for the calculation. The resulting grid is
placed at the origin (x, y)=(0,0) in the xy plane. If necessary, expand the
limits to check for the resulting grid (menu Options|Limits).
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•
Open the dialog Grid Arithmetics from the Grid menu and load the two
vertical grids, e.g. for R1 and R2.
•
Generate the difference grid, e.g. using the formula R2-R1, and save the
resulting grid using a new filename.
•
Open the dialog Vertical Grid of the referring object and press the key
combination ALT+o (letter „o“).
After loading the file the level difference grid is displayed (check for the level
displayed when moving the mouse within the grid’s area).
•
Alter - as required - the options on dialog Appearance with respect to
the level range of the difference grid.
Dialog Vertical Grid displaying a difference grid, using the
color palette „pal_0_20_step_2“ with areas of equal sound level
see also: chapter 12.6.1 "Default Color Palettes"
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5.4
Building Evaluation
According to the requirements of RLS-90 /17/ and using the map symbols
defined in this guideline, there is a fairly simple way of demonstrating for a
building close to a traffic route whether the predefined and maximum permissible rate levels on the basis of designated land use have been exceeded. It
is also possible to ascertain which storeys this is true for and which values are
to be expected at the most exposed position of the facade during the day and
night.
•
We activate - for better understanding and not because it is necessary - the
option „No calculation of Building Noise Map“ in the menu
Options|Building Noise Map (see chapter 5.4.1).
•
Insert the object „Building Evaluation“ with the corresponding icon from
the toolbox. For that, click inside the building plan for that building for
which an evaluation is supposed to be made.
•
After placing the first symbol we should adjust the size if necessary. All
further inserted symbols then have the same size.
5
Procedure
 Examples\05_Immissions\Industry.cna
If several or even all buildings or only buildings with a certain condition of a
project shall be evaluated we can use the command from the context menu
Modify Object, action „Generate Building Evaluation“ to insert the Building Evaluation symbols all at once (see manual "Introduction to CadnaA").
In this case CadnaA automatically places these symbols in the selected buildings. The name of the building, entered in the identically named edit box in
the edit dialog, will be automatically transferred into the corresponding input
box of the building evaluation symbol.
In order to generate a building evaluation only for buildings e.g. with a certain
height and/or base area a corresponding numerical condition can be defined.
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Action „Generate Building Evaluation“ with condition
To insert an expression for a condition activate the pertinent check box and
either enter an attribute (see CadnaA-manual „Attributes, Variables, and
Keywords“) via keyboard or select them from the list which opens by clicking
the button with the double-arrows.
With the above example would be generated symbols for all buildings which
have a relative height higher than 3 m and a base area bigger than 50 m². In
this case both conditions must be „true“.
Symbol Size
Adjust the symbol sizes via the table Building Evaluation (Tables
menu|Other Objects) using the context menu command Change Column
(see chapter 11.1.3), and also define the type of Land Use (if any). First insert
just one symbol and specify all settings as required. CadnaA will keep the
settings for all further building evaluation symbols when using the action
„Generate Building Evaluation“.
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Default situation: The building evaluation symbol is set for the upper
left building. The calculation has not been launched yet
When a building is evaluated, levels computed by CadnaA for all storeys and
in front of all facades are compared to the pertinent limit values or standard
values. The latter can be defined in two ways.
•
Double-clicking on the building evaluation icon opens the corresponding
dialog.
•
Activate the appropriate option for the standard values.
If the option „Determine from Designated Land Use“ is deactivated, you can
select the type of area by clicking the card-index icon next to the „Land Use“
box, and the type of noise can be selected in the „Use Standard Values for“
list box.
Although this building evaluation was originally aimed at traffic noise, this
flexible concept can also be applied to other types of noise like, e.g., industrial
noise.
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Building Evaluation of a building in a residential
area (WA), with respect to road traffic noise
Designated Land Use icon
The second way is to click the Designated Land Use icon and assign a type of
land use to an area by drawing a closed line around it. Then activate the option „Determine from Designated Land Use“. The standard values to be
compared should then be known.
When all buildings have been provided with a building evaluation symbol,
and the calculation is triggered by clicking the Pocket-Calculator icon on the
toolbar, the progress bar window will first display the calculation for the
specified receiver points and then the progress of the building evaluation.
In this building evaluation, calculations are performed and evaluated one after the other
•
for all buildings bearing this symbol,
•
for all storeys which result from the ratio of building height to storey
height (storey heights may be edited under button „Options“ on the edit
dialog Building Evaluation), and
•
for all outer facades.
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Building Evaluation Symbol after calculation
Upon completion of the calculation, the top semicircle of the icon indicates
the range of storeys where excess levels occur. If it remains blank, no excess
levels occurred, or no area of designated land use has been assigned. The bottom quarters display the levels according to the selected „Averaging Method“
for the first and second evaluation parameter (see chapter 6.2.5). By default,
these are the daytime level Ld and the night-time level Ln.
I-VII
7060
I-II
6858
I-III
6757
I-II
6959
I-III
6858
I-II
6959
I-II
7161
I-II
7161
I-II
7261
I-II
6252
Labeling of the buildings after calculation
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5.4 Building Evaluation
In some cases it could make sense to place the building evaluation symbol
outside the layout of the house. For that you can check the option „Use
different Calculation Point“ on the dialog Geometry and place the symbol
somewhere outside of the house without loosing the connection to this
building. The original coordinates will be saved.
•
Insert the symbol within the building base.
•
Open the dialog Geometry and check the pertinent option.
•
Close all dialogs with OK and push the symbol outside the building.
The calculation point is displayed with a connecting line (auxiliary polygon).
Attribute: USE_PCALC
Activation via Change Attribute|string: „x“
When transforming the Building Evaluation Symbol (via dialog Modify
Objects or via the context menu, action/command Transformation) the
connecting line will be transformed automatically.
Excluding Facades
In the edit dialog Building Evaluation if you click on the button
„Option|Exclude Facade“ another dialog opens in which you can mark
facades not to be taken into account for a calculation.

For the calculation options „Facade points acc. to VBEB“ and „Facade
points acc. to CNOSSOS“ (see chapter 5.4.1), the exclusion of façades
is not possible for the time being.
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Dialog Exclude Facades
In order to exclude a facade, click once on the identifier in the upper table
(e.g. F01) or double-click on a facade in the graphics below.
Marked facades are excluded from the next calculation. On the lower graphic,
the excluded facade is marked by a thick black line and the black dot (facade
point) gets deleted. By clicking again on the identifier of a facade or doubleclicking in the graphics this will again be included in the calculation.
The exclusion of non-relevant facades can save a reasonable amount of
calculation time when evaluating a building noise map. At maximum 256
facades can be excluded.
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Importing Building
Evaluation Symbols
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5.4 Building Evaluation
In case the buildings and the accompanying building evaluations are saved in
separate files after a calculation run, no proper link between both objects is
established when re-importing the building evaluations into the file with the
buildings (via menu File|Import). This causes all building-related
evaluations to fail (e.g. via the ObjectScan, Grid menu - requires option XL),
since the corresponding data for the buildings does not exist (e.g. the building
noise levels HB_LP1 to HB_LP4). In those situations, the link between the
buildings and the building evaluations has to be reestablished. Use the
command Link Buildings to Building Evaluations on the Extras menu to
update the link.

Please consider that when loading the building evaluations via the command PCSP|Load PCSP-Tiles (Calculation menu) the link is
updated automatically (see chapter 6.10 "PCSP - Program Controlled
Segmented Processing"). The above statements just hold when
importing the calculated building evaluations via the menu
File|Import.
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5.4.1 Building Noise Map
5.4.1
Building Noise Map
Using the object „Building Evaluation“ (see chapter 5.4) enables to display
the maximum sound level across the storeys of a building where an exceedance of a limiting value occurs. Furthermore, a colored building noise map
based on the level calculated for each storey is produced.

In conjunction with the use of variants (see chapter 14.2) to calculate
different scenarios, also level difference maps at building facades can be
generated (see chapter 5.4.3) and displayed.
•
Insert the object „Building Evaluation“ with a mouse click on the
building plan.
•
In edit mode, double-click on the border of the building evaluation symbol and define a standard value by selecting the pertinent option.
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5.4.1 Building Noise Map
The options for the data displayed on the building noise map are available on
the menu Options|Building Noise Map.
5
•
If necessary deactivate the option „No Calculation of Building Noise
Map“ and set the further desired parameters by input or selection.
•
Start the calculation with the pocket calculator from the toolbar or with
menu command Calculation|Calc.
Dialog Building Noise
Map/ Building
Evaluation
Dialog Building Noise Map/Building Evaluation (on Options menu)
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5.4.1 Building Noise Map
DIALOG OPTIONS
Calculation
Selecting the method used to generate facade sections:
•
Facade points via facade lengths: The distribution of the facade points
along the facades of the buildings is based on the minimum and
maximum facade length.
•
Facade points according to VBEB: The distribution of the facade points
follows the regulation in VBEB /113/. The minimum facade length is
therefore 2.5 m, the maximum 5 m.
•
Facades according to CNOSSOS: The distribution of the facade points
follows the regulation for CASE 1 from CNOSSOS-EU /16/. Select the
option „Facade points via facade length“ to apply CASE 2 from
CNOSSOS-EU and enter 5 m for „maximum facade length“.
Facade points via/acc. to
...
5
CadnaA subdivides the facade based on the entered length and inserts a level
symbol into each section.
minimum/maximum
Length of Facade
This value specifies at which distance the facade points are generated off the
buildings facade surface. In conjunction with the configuration setting for
„Minimum Distance Receiver - Reflector“ (see chapter 6.2.8 "Reflection
Tab") this will define whether the facade levels consider the reflection at the
building’s facade or not.
Distance ReceiverFacade (m)
The default value is 0.05 m. The default setting for „Minimum Distance
Receiver - Reflector“ of 1 m means that, the reflection at the building’s facade
is not considered in the facade levels.
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Additional Free Space
Is the distance from the facade point to the next obstacle smaller or equal to
the value entered, no façade point/s will be generated and calculated. This
may be useful when buildings have been imported having small gaps between
each other, but should calculated as without gaps. The default value is 0 m.
Averaging Method
This selects the method for the calculation of the characteristic noise level of
each building from the noise level of the facades (arithmetic, energetic
average value, minimum or maximum value). The resulting value is shown
inside the building evaluation symbol for the first two evaluation parameters
(see chapter 6.2.5 "Evaluation Parameters Tab").
No Creation of Building
Noise Map
By activating this option, no noise map is calculated and displayed for the
buildings. The building evaluation, however, is still executed as long as the
symbol/s are activated.
5
Appearance of
Building Noise Map
Show Facade Points
Select from the list box the facade points/levels to be displayed on the building noise map. The floor numbering as selected on the dialog Miscellaneous
is used (see chapter 9.15).

The storey’s designation can be displayed on the Result Table using the
string variable STW (see chapter 2.1 in the CadnaA manual „Attributes,
Variables, and Keywords“).
Symbol Type
Either „Octagon“ or „Ribbon“ can be selected.
Size of Exceeding/Not
Exceeding Symbol
The size of the facade point symbols exceeding or not exceeding the limiting
value may differ. Selecting the unit (m) will adjust the size of the symbol
when change the scale, but not when selecting the unit (mm).
Color Symbols according
to Level
Activating this option will colorize the facade point symbols according to the
color palette specified via the menu Grid|Appearance.
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When this option is activated (default setting) the facade level displayed for
each face point will apply the rounding rule as specified in the respective
building evaluation symbol. Otherwise, the level not being rounded off will
be displayed (integer value). In conjunction with the color palettes (see chapter 5.3.2 "Grid Appearance" and chapter 12.6 "Color Palettes") and the option „Size of Exceeding/Not Exceeding Symbol“ this option can be used to
define a rule for the color and the size of the facade point symbols applying
the rounding or not.
option „Use rounded values“ activated
(file BuildNoiseMap - Option Use rounded
values ON.cna):
option „Use rounded values“ deactivated
(file BuildNoiseMap - Option Use rounded
values OFF.cna):
The level at the lower left facade point is larger
than 64.0 dB(A), but smaller than 64.1 dB(A). So,
the limiting value of 64 dB(A) is respected considering the rounding rule 0.1 dB.
The rounding rule is not considered when
displaying the facade point levels. So, all levels
larger than 64 dB(A) will be exceedances and displayed as such. *)
Use rounded values
5
*) This setting corresponds with former releases of CadnaA (prior to release 4.1).
Open the file BuildNoiseMap-Option Use rounded values
ON.cna in directory Examples\05_Immissions. The limiting value in this
example is 64 dB(A) and the rounding used is 0.1 dB. Thus, applying this rule
to 64.1 dB(A), for example, will cause a rounded value of 65 dB(A). Values
form 64.0 to 64.1, however, will be rounded off to 64 dB(A) and respect the
limiting value, consequently. Displaying the Result Table it can be checked at
which facade points on the ground floor the level ranges between 64.0 and
64.1 dB(A).
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5.4.1 Building Noise Map
In the next figure, the nominal level exceedances are indicated by a red color
and an enlarged size of the facade point symbol.
Print in Symbols
Activation of this option will show either the level - in addition to coloring within the level symbol. Alternatively, the number of the facade point number generated by CadnaA is displayed. The facade levels can be displayed in
the Result Table (see chapter 11.2) by selecting from the list box „Receivers
from Building Noise Map“. The facade point numbers can be displayed in
the Result Table by use of the string variable FASSNR.
Apply
By clicking the „Apply“ button, the actual the settings are applied
instantaneously, without closing the dialog. When changing now the facade
length the effect is just visible after a new calculation. By clicking the
„Cancel“ button the altered settings will be ignored.
3D-Special View
The building’s facades are also displayed in colors on the 3D-special view according to the specified grid caption after a calculation.
Dialog Options
Arithmetic
With the „Arithmetic“ field you are able to calculate different formula for or
with the noise map of buildings, e.g. level-difference-map for building noise
(see chapter 5.4.3)
5
In case a horizontal receiver grid has already been calculated you can allocate
interpolated grid values to facade points. A separate calculation of a noise
map for buildings is unnecessary which would save calculation time.
Independent from the number of defined evaluation parameters (see chapter
6.2.5) the calculation results of the horizontal receiver grid provides a basis
for the building evaluation.

Prior to the allocation is that building evaluation symbols have to be
addressed to the relevant buildings and the facade points been
generated which can be generated by a „dummy“ calculation with a
point source.
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5.4.1 Building Noise Map
1.
calculate the receiver grid
2.
generate face points with calculation of one single noise source (e.g.
point source - all other noise sources deactivated with Modify Objects,
action „Activation“, „Deactivate“ for all objects except the buildings
and the building evaluation symbols
3.
calculate the dummy noise map of buildings with the calculator symbol
on the toolbar
4.
On dialog Building Noise Map, dialog range „Arithmetic“ enter the
expression r0 and click the button „Perform Calculation“.
By the expression r0 the interpolated calculation results of the horizontal grid
will be allocated to the corresponding evaluation parameters of the facade
points, not depending in what evaluation parameter’s input box (in this
example Day|Night) the expression was entered. Subsequently, when selecting one of the evaluation parameters from the list on the toolbar, the respective results are displayed within the facade points.
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To address interpolated results of the horizontal receiver grid, coordinates or
the ground height to the facade points, the following additional expressions
can be used in a formula:
5
Example
Input
Result
r0
allocation of the results from the horizontal grid to all the corresponding
evaluation parameters
r01 to r04
allocation to the corresponding evaluation parameter LP1 - LP4
(r01 allocates the result to LP1, r02 to LP2 etc. - special application)
x|y|z
evaluates the corresponding x-, y- or z-coordinate of the facade point (z
allocate the z-coordinate to the facade point - special application)
g
evaluates the ground height at the facade
iif(STW==1, r0, LP1)
(in words: if it is the first floor then address the interpolated result from the
grid - otherwise not, i.e. keep the existing value)
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5.4.1 Building Noise Map
Using the CadnaA option X or XL (see Chapter 15 - Options X & XL) also
facade points are selectable as object type for evaluation.
Option XL
For the facade points the following attributes are available:
Attribute
Explanation
TOT_EINW
total no. of inhabitants of a building to which the corresponding
facade point belongs to
FAC_EINW
number of inhabitants assigned to a facade point, with the same
number of inhabitants is assumed per facade length
FAC_EINW_xy
number of inhabitants assigned to a facade point, weighted by applying the following options:
- for x:
L inhabitants weighted using the length of each facade section
C inhabitants per facade section
- for y:
A for all facade points (includes also the deactivated ones, if any)
(blank) just the „active“ facade points are considered
STW
floor identifier (ground floor=0, 1st floor=1, 2nd floor=2 etc.)
FAC_NR
number of facade points counted from the first point of the building
(FAC_NR=1, FAC_NR=2 etc.) to the last facade point
FAC_LEN
corresponding facade 2D-length (m) of the facade point
TOT_LEN
sum of all facade lengths referring to the facade points
TOT_LEN_N
sum of all facade lengths referring to the facade points, facade lengths
deactivated by the option „Additional Free Space“ are not considered
FAC_AREA
corresponding facade area (m²) of the facade point
TOT_AREA
sum of all facade areas referring to the facade points
TOT_AREA_N
sum of all facade areas referring to the facade points, facade areas
deactivated by the option „Additional Free Space“ are not considered
TOT_FAC
number of facade sections
TOT_FACPTS
number of facade points
TOT_FACP_N
number of facade points, facade points deactivated by the option
„Additional Free Space“ are not considered
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5.4.1 Building Noise Map
CENTER_X
x-coordinate of the buildings center point
CENTER_Y
y-coordinate of the buildings center point
CENTER_ANG
angle between the buildings center point and a facade point, North
direction = Zero
BLDG_AREA
building‘s ground area, for facade points
BLDG_ID
building ID (for facade points) - for internal use only
LPFLMAX1 .. 4
maximum level per storey for evaluation parameters 1 to 4
LPCNOSS1 .. 4
level according to CNOSSOS-EU per storey for evaluation parameters 1 to 4 (see chapter 15.1, section „CNOSSOS“ in the CadnaA
Reference Manual for details)
If, e.g. the assigned number of inhabitants to a facade point should be
evaluated select „Facade Point“ as object type and enter the following
attributes and expressions in the input boxes:
for „Formula for Summation“: FAC_EINW
for „Formula for Total“: sum/num
for more information see chapter 15.1 "Object-Scan"
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5.4.2
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Result Table for the Building Noise
With the generator of the new result table you can define a table showing the
results in a desired form.
Immission Point
Land
Name
ID Storey
IP 01
IP 02
IP 03
Building 01
Building 01
Building 01
Building 02
Building 03
Building 05
Building 06
Building 07
Building 08
Building 08
Building 13
Building 19
Building 19
EG
EG
EG
EG
EG
1.OG
EG
EG
EG
EG
EG
1.OG
1.OG
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
MI
Limiting Value
Day
Night
dB(A)
dB(A)
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
64
54
rel. Axis
Station Distance Height
m
m
m
22
21.51
0.50
0
53.58
1.50
51
35.94
1.50
123
9.19
2.50
126
8.80
2.50
133
12.08
2.50
107
9.70
2.50
91
8.83
2.50
61
12.24
5.30
43
11.82
2.50
26
11.71
2.50
165
9.57
2.50
162
9.67
2.50
81
8.59
2.50
141
12.78
5.30
138
12.81
5.30
Lr w/ Noise Control
dL req.
Day
Night
Day Night
dB(A)
dB(A) dB(A) dB(A)
59.6
49.3
53.2
43.0
51.2
41.0
68.3
58.1
4.3
4.1
68.7
58.5
4.7
4.5
65.1
54.9
1.1
0.9
68.1
57.9
4.1
3.9
68.6
58.4
4.6
4.4
66.7
56.5
2.7
2.5
66.9
56.7
2.9
2.7
66.8
56.6
2.8
2.6
64.5
54.2
0.5
0.2
64.5
54.2
0.5
0.2
65.7
55.4
1.7
1.4
66.4
56.2
2.4
2.2
66.4
56.2
2.4
2.2
Result table with receiver points taken from the noise map for buildings
If you want to look at the results for the receiver points taken from the noise
map of the building in addition to the standard receiver points, please activate
the option „Receivers from Building Noise Map“ on the dialog Edit Result
Table and choose the desired levels/storeys from the list box.
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Dialog Edit Result Table
To show also the column Storey, insert a new line in the edit box’s result table
if necessary.
A double-click on the line will open the edit box’s table column.
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Column-Edit dialog of the Result Table
Enter the parameters shown above and close the dialog box by clicking OK.
The string variable STW represents the corresponding storey.

The string variable STW displays the pertinent storey identifier.
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5.4.2 Result Table for the Building Noise
Following string variables can be used in the Result Table to view more information about the facade points of a Building Noise Map:
STW
floor identifier:
EG = ground floor
1.OG = first floor
2.OG = 2nd floor
etc.
FASSNR
facade point number of the building noise
map, starting with the first polygon point of
the building.
Example: On the basis of the facade partitioning (menu Options|Building Noise
Map) 12 level icons are generated together
for all sides of the building. Consequently,
they will be covered intern with the facade
numbering from 1, 2, 3 etc. till 12. If each
level icon has even 5 storeys so each storey
will be assigned to the corresponding facade
number.
DIR
degree No. 0-360 where 0 is the North direction
HIRI
direction with one letter (N-North, O-East,
S-South, W-West)
HIRI2
direction with two letters if necessary (e.g.
NW-North-West, SO-South-East)
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5.4.3 Level Difference Map for Building Noise
5.4.3
Level Difference Map for Building Noise
With the so-called Building Noise Map in conjunction with using variants the
differences in facade levels at buildings can be calculated easily.
First, we calculate the building noise maps for all variants with Calculation|Calc, option „All Variants“. If we toggle variants by selecting the
variant name at the toolbar the respective result is displayed on the screen.
5
To better recognize the levels, displayed in the symbols, deactivate the option
„Color Symbols according to Level“, if necessary, or choose a different color
palette with Open Palette in the menu Grid|Appearence| Option (see
chapter 5.3.2).
We calculate the level differences by subtracting the results of the variants.
For that, open the dialog Options|Building Noise Map and enter a formula
in the dialog range „Arithmetic, assign active Variant“.
Calculate Level
Differences
Example
We calculate the first variant V01 with the actual situation and the second
variant V02 with the actual situation plus noise protection measures, e.g. a
noise protection wall. What level differences does the noise protection wall
gain at the facades?
After calculating all variants (Calculation|Calc, option „All Variants“), we
create another variant, e.g. V03 - differences - and activate this variant by
selecting its name from the list box in the toolbar.
In the dialog Options|Building Noise Map, option „Arithmetic, assign
active Variant“ enter the following:
LP1V01 - LP1V02
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- Variants.cna
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5.4.3 Level Difference Map for Building Noise
Click the button Perform Calculation. With this expression all evaluation
parameters will be calculated if no other arithmetic field of has been checked.
5
If you want to calculate only a specific evaluation parameter you have to
indicate the number of the desired evaluation parameter (LP1..4).
The expression in the above dialog means evaluation parameter 1 (LP1) of
the variant 1 (V01) minus evaluation parameter 1of the variant 2 (V02).
The row names of the arithmetic fields (in this example „Day“ and „Night“)
are changing depending on the name defined in the Calculation|
Configuration, „Evaluation Parameter“ tab.
The button „Apply“ displays the result immediately without closing the
dialog. Otherwise close the dialog by clicking the OK button.
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5.4.3 Level Difference Map for Building Noise
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In this example the variant V03 will be overwritten if we calculate all
variants again. The calculation of the level differences must be
refreshed. The map of level differences for buildings is always displayed
in the activated variant and therefore overwrites the existing result.
The functions, which you can use in the Arithmetic box, are identical with
those from the Result Table.
For function and operators see CadnaA-manual "Attributes, Variables, and
Keywords".
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Chapter 6 - Calculation
CadnaA enables
•
the calculation of sound propagation according to standardized
procedures
and
•
with settings that are defined by the user.
This chapter deals with the second task and its possibilities with CadnaA and
is therefore more concerned with the physical aspects of sound propagation.
This is very important because CadnaA is used for expert work, in scientific
work at universities and in lectures. Although the professional usage requires
a strict application of the procedures fixed by standards and guidelines, it can
be very useful the be able to process special calculation tasks which are not
covered by the regulations in detail.
Especially, this concerns the handling of reflections with higher order.
According to the standard procedures a reflection of the first order is only
dealt with according to the mirror image method, So just a single reflection
of a ray at a flat surface. In case more orders of reflections contribute to the
total result (e.g. at the building facades on both sides of a road), this will be
taken into account - in the majority of road and railway noise standards - by
calculating analytically a correction for multiple reflections from the geometrical and acoustic parameters.
This strategy fails if the geometry of the building lateral to the road is completely different and varies from building to building. The same problem exists with the noise level in backyard locations. Those cases can just be treated
by calculating higher orders of reflection.
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6.1 Sound Rays and Reflection
6.1
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Sound Rays and Reflection
CadnaA is able to calculate reflections completely up to higher order. It is
clear that this increases calculation times, because the number of rays grow
exponentially with this reflection order. With the possibility to show all these
calculated rays at the screen, CadnaA is a very helpful tool when teaching
about sound propagation.
The chapter chapter 6.1.1 "Sound Rays at Point Sources", chapter 6.1.2
"Sound Rays at Line and Area Sources" and chapter 6.1.4 "Reflection" treat
the contents of a major publication, see reference /102/. It explains the way
of segmentation of extended sources, like line and area sources and the projection technique applied with this. Furthermore, the calculation of multiple
orders of reflections is explained, again applying the projection technique. It
is worth mentioning that there are still some software packages available that
do not apply any projection technique when segmenting area sources to assess the direct path. The partial levels of reflections evaluated with extended
sources - like roads or parking lots - are arbitrary in this case and not conform to the specification found in the respective standards or guidelines.
Chapter 6.1.7 explains how paths of rays can be displayed. Because of the selective display possibilities for the different orders (by using groups), the handling might look a bit complicated, but it is an excellent tool for clarifying the
executed calculation and therefore can be helpful in a technical report in
many cases. We recommend that the detailed examples be understood step by
step. Once you have taken this initial hurdle the inclusion of ray representations in drawings and text documents is easily possible.
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6.1.1 Sound Rays at Point Sources
6.1.1
65
Sound Rays at Point Sources
In a physical sense a wave field goes out from a source Q which transports
the sound power in all directions via the movement of the air particles. Because the surface of the spheres’ hull expands with increasing distance, and
the sound power is distributed over the hull over a certain period of time, the
sound intensity decreases and therefore the sound pressure level, too. With
increasing distance source - receiver it becomes quieter.
6
Sound propagation from Source Q to Receiver Point RP physical (left) and numerical (right)
If CadnaA calculates, the distance between source Q and receiver RP will be
determined and, with the sound power level of the source, the sound pressure level at the receiver point will be calculated with analytical formulas
which have been derived from the physical model. The wave field is in a certain way replaced by one ray from source to receiver.
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Chapter 6 - Calculation
6.1.1 Sound Rays at Point Sources
If there are many sources there are also many sound rays which have to be
considered in the calculation. For all receivers affecting sound rays the calculated proportion of the level will be added energetically.
IP1
IP1
Q6
Q6
Q1
Q1
IP2
Q2
IP2
Q2
6
Q3
Q3
Q4
Q5
Q4
Q5
IP3
5 Sources and 3 Receiver (IP)
IP3
The Sound Rays
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6.1.2 Sound Rays at Line and Area Sources
6.1.2
Sound Rays at Line and Area Sources
Even in the case of calculating the noise level from an extended source as the
area source shown in fig. A, a distance has to be found that can be used in the
equation of propagation. This may be wrong if the pivot of the extended
source is used as starting point of the ray. Since, actually, each arbitrary portion of the area source emits sound, the same value of a level must result if
the total stripe according to figure B is to be subdivided and the sound pressure level at the receiver point is calculated as the sum of the levels of the 5
contributions from the partial sources FQ1 till FQ5.
6
IP
FQ
A: Area source with sound ray
IP
FQ1 FQ2
FQ3 FQ4
B: Partitioning of the area sources
However, the partial sources, according to figure B, result in different partial
levels because of the different distances. On the basis of the energetic
addition a higher sound pressure level results from fig. B than from taking
into account only one ray emitted from the pivot as shown in fig. A.
This error has been avoided in CadnaA by partitioning each extended line or
area source in sufficiently small parts for automatic calculation.
But these partial areas do not have the same size as shown in figure B. They
become even smaller the closer the corresponding section of the extended
source is to the receiver.
This dynamic division, which must newly be calculated for each receiver,
leads to a considerably faster calculation in comparison to the equal division.
The following figure shows the sound rays, which CadnaA takes into
account, with the irregularly shaped area source provided below.
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6.1.2 Sound Rays at Line and Area Sources
IP
6
The sound rays of an area source considered by CadnaA.
The same applies to line sources. By the road shown in the following figure
the borders of the stripe are the axis of the outer lanes which are each considered as line sources and taken into account in the calculation of level .
IP
The sound rays of a roads considered by CadnaA.
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6.1.3 Projection at extended Sound Sources
6.1.3
69
Projection at extended Sound Sources
The automatic division of an extended sound source into smaller partial areas
depending on the distance of the receiver (see chapter 6.1.2 "Sound Rays at
Line and Area Sources") is not sufficient to avoid errors in the calculation of
sound pressure levels.
6
IP
Calculation of the area source „soccer field“ with two sound rays
Let us take the example of a soccer field as in the upper figure. For a noise
calculation at the remote receiver point IP CadnaA would split the soccer
field into two partial areas and would therefore take into account two sound
rays. This is correct for the shown situation. Now a shielding club house with
a height of 8 m is located in the position shown in the following figure.
IP
Clubhaus
Soccer field with partially shielding club house
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Chapter 6 - Calculation
6.1.3 Projection at extended Sound Sources
In the calculation of both displayed sound rays, screening and therefore a
lower sound pressure level occurs in each case. But, in fact, not all partial areas, which are included in the calculation with the paths of the two rays, are
shielded by the building. The resulting sound pressure level would be too low
in the present example.
CadnaA avoids this error by using a projection method.
6
With that, in the first step the area sources will be divided into shielded and
non-shielded areas and in the second step subdivided according to the relation of area size to receiver distance. In this way, in the present example, 12
partial areas are created: altogether, nevertheless, because of the large distance from the receiver (340 m), 8 areas are not shielded and 4 areas are
shielded.
IP
Clubhaus
Two step division according to shielding objects in the path of rays
and the distance of the receiver
In the present example the calculation results in 44 dB(A) of free sound
propagation, 39 dB(A) in the calculation of the situation with the club house
without using the projection method and 42 dB(A) with correct division resulting from the use of the projection method.
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6.1.3 Projection at extended Sound Sources
6 11
The next figure shows the projection method with a road.
Projection method for a road
Both axis of the outer road lanes - that is the margin of the road stripe in the
CadnaA presentation - are first divided according to the shielding objects between receiver and road. Then a subdivision occurs according to the distance
criteria.
Projection method for reflecting sound parts
Much more complicated are the relations in the projection of the reflecting
sound parts dealt with in the next chapter. The figure 3 above shows the construction of both sections for the axis of the outer road lanes which are necessary because of the reflecting building. The same method - graphically
hardly to explain - will also be applied by CadnaA for the multiple reflections
dealt with further on.
Although the projection method naturally extends the calculation considerably it should always be switched on for a detailed calculation like „acoustical
zoom“. After all, even in the simple situation 12 paths of rays instead of 2
must be calculated.
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6.1.4 Reflection
6.1.4
6 13
Reflection
Additional sound rays appear in the sector of the path of sound propagation
from reflective objects which affect the receiver and could increase the sound
level.
The mirror-source method will be applied regularly by the calculation of reflection and it is therefore assumed that the reflective areas are „acoustically
even“. In the experience of engineering the numerical calculation of diffuse
reflection has only been achieved over the statistical approach for the density
of scattering objects (see e.g. /96/). A numerically correct resolution for
point-precise calculation with diffuse reflection is dealt with in /100/. But
this is still a lavish resolution for the professional practice.
On the other hand the mirror-source method has been proved excellent for
the propagation of sound, also in cases strictly without even areas. The propagation of sound including reflection up to an extremely high order has been
described precisely (see to this /101/ and /41/) for industry halls in which
the surfaces areas are anything but even (through extensions such as pipelines
and so on).
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6.1.4 Reflection
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6.1.5 Reflection of the 1st Order
6.1.5
6 15
Reflection of the 1st Order
The calculation of the first reflection is required by certain standards if this
reflection contributes to the sound level at the receiver (e.g. according to the
guidelines RLS-90 /17/, Schall03 /23/ and ISO 9613-2 /8/).
The calculation occurs in three steps which have to be carried out for each reflective area according to each pair source (Q) - receiver (IP).
1.
constructing the position of the mirror sources,
2.
sectioning the connecting line of the reflected source - receiver point
with an area and determining the breakhrough-point,
3.
calculating the part of the sound level according to the longer path of
the ray over the reflecting area including the absorption coefficient of
this area.
In the example shown below two parts of sound level are taken into account
at the receiver (IP) which are calculated from the displayed paths of rays.
The paths of rays with the reflection of the first order
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Chapter 6 - Calculation
6.1.5 Reflection of the 1st Order
Important for the correct calculation of reflection, according to the mentioned guidelines, is that all reflections of the first order be checked and, if
necessary, be included in the calculation. That is not obvious - software programs exist which check, starting at the receiver, a ray only till the first reflector crosses the path of the ray in the plan, even if this reflector is not affecting
anything because of the low height and the area lying behind which reflects
the ray. The calculation of reflection must, as in the example of picture A,
also find a level-raising contribution if, as in picture B, a low obstacle at the
base seems to block the ray’s path.
6
H=8m
IP
H=1m
Q
The paths of rays for the reflection of the first order with
obstacles in the path of the ray.
A typical example of this case is shown in the next figure. The program only
investigates up to the first reflector which is found, then at the house on the
left side of the road the amount of reflection which is caused by the high
building is not taken into account only because a 1 m high wall is located
between this high building and the four lane road. This calculation is not in
accordance with RLS-90 in this case.
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6.1.5 Reflection of the 1st Order
6 17
Besides this, CadnaA takes into account reflections if screening objects obstruct the path of the reflected sound ray. The part of the sound level which
was caused by the reflecting sound at the receiver point is then reduced by
the value which results from the screening calculation for the path: mirrorsource - receiver.
6
For the calculation of the sound level at the left residential building, according to RLS90, the
reflection of the traffic noise on the high right building has to be calculated despite the low wall
between the road and the building.
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Chapter 6 - Calculation
6.1.5 Reflection of the 1st Order
CadnaA also calculates the reflection for extended sources such as line or
area sources, but these objects will be split into sufficiently small partial
sources. The figure shows the already familiar soccer field with three buildings located in the neighborhood and the paths of rays taken into account.
6
The paths of rays taken into account in a calculation of sound levels on a soccer field
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6.1.6 Reflections of Higher Order
6.1.6
6 19
Reflections of Higher Order
In calculating reflections of second order all valid mirror-sources have to be
reflected again on all reflecting areas to prove the validity of each reflection
and to calculate the corresponding path of the ray.
The number of rays with a further order of reflection results from the product of the number of reflections from the last order multiplied by the number of valid reflectors. The specification of this numeric method is found in /
100/.
It is obvious that the number of possible reflections explodes with an increasing number of orders. Calculations up to higher orders are only completely possible for very restricted arrangements. On the other hand, a
reflection has to be calculated first before its contribution can be evaluated as
irrelevant.
CadnaA enables the calculation of reflections of high orders for all type of
sources. The paths of ray can be displayed and the sound level contributions
of the reflections are separately identified. According to the specifications of
the standards for the source type Road and Railway with activating these
standards only reflection of first order are calculated using mirror-image
method - reflections of higher order are taken into account with a penalty for
multiple reflections.
An example for the complete calculation of reflection up to the 10. order is
shown with the backyard in the next figure. A point source located in front of
the opening beams into the backyard, and the sound level shall be calculated
at the represented receiver IP.
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Chapter 6 - Calculation
6.1.6 Reflections of Higher Order
Q
1.Ordnung
Q
2.Ordnung
6
Q
Q
Q
3.Ordnung
5.Ordnung
7.Ordnung
Q
Q
Q
4.Ordnung
6.Ordnung
8.Ordnung
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6.1.6 Reflections of Higher Order
Q
9.Ordnung
Q
6 21
10.Ordnung
All ray paths for each reflection order in a backyard
6
Q
0. - 10. Ordnung
All possible ray paths of rays in a calculation up to the 10. order
Arbitrary arrangements of objects can be taken into account for a calculation
of reflections. With this technique it is possible to perform the calculation of
the sound level corresponding to the reality in cases not corresponding to the
valid guidelines.
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6.1.6 Reflections of Higher Order
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6.1.7 Displaying Sound Rays
6.1.7
6 23
Displaying Sound Rays
When the option „Generate Rays“ is activated in the dialog Receiver all
calculated rays with this target point are inserted as auxiliary polygon lines.
With double-click on such a ray its contribution to the sound level at the
receiver is indicated. This sound contribution is shown in the field „ID“ with
its proportionate level, e.g., RAY_419_00 which signifies that the direct
sound ray (_00) contributes 41.9 dB.
The rays are shown on screen as if they cross screening objects straightly nevertheless screening is calculated taking into account vertical and lateral
diffraction. In this case an s will be attached in their identifier. A shielded ray
of the eighth order for which a calculation of diffraction has been enforced
may have an identifier RAY_419_08s.
Due to this, rays with a certain order of reflection can be displayed or
switched off easily in CadnaA with the efficient group function (menu
Tables|Groups see chapter 14.3 "Groups"). If the rays are displayed, all
diffracted sound rays can be switched off in the representation by
deactivating the group with the expression *_??s.
With corresponding settings for all deactivated objects in Options|
Appearance (see chapter 9.5 "Object Appearance") you can enforce the
diffracted and non-contributed, mostly irrelevant rays to disappear completely.
But the best is learning by doing - trace step by step the following example.
•
Start CadnaA
•
In Options|Limits enter the values for the limit as shown in the
following dialog.
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Chapter 6 - Calculation
6.1.7 Displaying Sound Rays
Insert the following objects
•
Point source with PWL 100 dB, Name Q1 - coordinates 20/5/5
•
2 buildings with a height of 25 m and Reflection loss of 0 dB:
- building 1 (80/60, 85/60, 85/100, 80/100)
- building 2 (0/130, 5/130, 5/160, 0/160)
•
Click in the toolbox on the icon and enter the value 80 via the keyboard hereby an edit dialog opens to enter a polygon point - press the TAB key
and enter the value 60 - confirm with OK and enter the next value for the
second pair of coordinates.
•
After inserting the coordinates of the first building, quit the insertion
mode by clicking with the right mouse button.
•
Again with the right mouse button, click once on the line of the building
plan - the edit dialog opens.
•
Click on the button „Geometry“ and enter a building with a relative
height of 25 m.
•
Repeat this for the second building. The building height is adjusted
automatically.
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Chapter 6 - Calculation
6.1.7 Displaying Sound Rays
•
2 Receiver points:
I2 (35/110/5) and
I3 (35/170/5)
•
Click on the corresponding icon in the toolbox
•
Enter the coordinate via keyboard and close the edit dialog Polygon
Point by clicking OK
•
Open the edit dialog by clicking with the Right mouse key on the margin
of the receiver point.
•
Confirm with OK.
•
In Calculation|Configuration|Reflection adjust a maximum reflection
order of 2 or more
The rays for the receiver I3 shall be displayed.
•
In the edit mode, open the edit dialog for receiver I3 by double-clicking
on its border and activating the option „Generate Rays“.
•
Now start the calculation with a click on the Pocket Calculator symbol on
the toolbar.
The following representation occurs after the calculation. CadnaA has calculated the direct ray, a reflection of the first order and a reflection of the sec-
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6.1.7 Displaying Sound Rays
ond order. (CadnaA calculates reflections completely up to the specified
order - shall we bet that there are no more possible paths?)
H o us e 2
I3
I2
H o us e 2
H o us e 1
I3
I2
Ho us e 1
6
S our c e
situation
S o ur c e
after calculation and display of rays
After double-clicking a ray - or by Tables|Other Objects|Aux.Polygon you can identify the rays on the basis of its ID, e.g., RAY_419_00 which
means that the level contribution of this ray is 41.9 dB and the last two digits
indicate the order of reflection. Double zero is the direct ray without
reflection, 01 is a reflection of the first order, 02 of the second order and so
on.
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Note the possibility in CadnaA in the tables - if you click on a data
record, e.g., of the table Other Objects|Aux. Polygon the corresponding ray in the diagram will be marked and can easily be identified.
Now only rays of the second order shall be displayed. This is in our example
simplified by directly switching off the non-desired ray in the corresponding
edit dialog on its ID field. But the deactivation of rays described in the following way is, however, with complex layouts the only realistic alternative.
•
Insert in Tables|Group a new table row (press the INS-key), doubleclick it and enter the expression *_02 in the same-named field and confirm with OK.
•
Insert a second line after the first one and enter the expression R*.
•
Deactivate this group (just enter a minus character - in the column Mark
„M.“). After confirming with OK you will only see the desired group with
rays of the second order.
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 Examples\06_Configuration\DisplayRays.cna
Chapter 6 - Calculation
6.1.7 Displaying Sound Rays
If the deactivated rays are displayed as bright grey dashes, let them disappear
completely - this representation would still cover all activated rays in more
complex situations. For this, use Options|Appearance| (deactivated) see
chapter 9.5 "Object Appearance".
To get to know the deleting of rays and the handling with shielded rays we
recommend you do the following exercise.
•
Activate all groups again in Tables|Group
•
Click on the House 1 and copy it in a position with a left offset so that
only a ray of the second order is intersected (see following figure)
6
House 2
I3
I2
House 1
Source

 Examples\06_Configuration\DisplayRays2.cna
The rays need not to be deleted. Just restart the calculation and the rays
are updated.
Now start a new calculation - click on the Pocket Calculator in the icon bar.
The ID of the ray which intersects the new building now contains the identi-
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6.1.7 Displaying Sound Rays
6 29
fier RAY_220_02S. To eliminate only the shielded rays from the representation
•
insert a new row in Tables|Group,
•
enter *s in the field expression and deactivate this group.
The screened ray has disappeared.
6
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6.2 Configuration
6.2
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Configuration
In developing CadnaA, it was, and continues to be, our goal to give the professional user the desired freedom of choice and control while relieving those
only interested in overall results from having to master all the available options. This complexity and flexibility of CadnaA is particularly evident when
large stocks of data have been entered which are then to be processed under
the Calculation|Configuration menu.
To meet the requirements for the calculation according to EC-Directive on
Environmental Noise CadnaA offers a flexible concept for defining and calculating evaluation parameters (see chapter 6.2.5). This concept enables to select from a number of pre-defined evaluation parameters (levels for single or
combined time intervals) and some more specific parameters (such as the uncertainty Sigma). Furthermore, you may define your own evaluation parameters using formulas.
In CadnaA up to four evaluation parameters can be calculated
simultaneously, either for single receiver points or in a receiver grid (in
addition to the ground).
The dialog Calculation|Configuration serves to specify all settings
required for the calculation, and, quite conveniently, to save these settings
with the calculated project file. There are various tabs for groups of options
within this dialog. Click the tab for the desired group to specify and select the
options.
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6.2 Configuration
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Chapter 6 - Calculation
6.2.1 Country Tab
6.2.1
Country Tab
6
From the list box „Country“ a country’s name or a group designation is
selected where specific standards or guidelines for all noise types are linked
to. In the list boxes for „Industry“, „Road“, „Railway“, and „Aircraft“ the respective guidelines/standards used in a calculation are displayed.
Country
When selecting the option „user-defined“ from the list box „Country“ a calculation procedure - depending on availability - can be selected for each noise
type individually. Please consider that not all standards/guidelines are linked
to a group designation „Country“.
Option „user-defined“
Depending on the actual selection the options available on the various
configuration tabs differ.
Via the buttons „Open Configuration“ and „Save Configuration“ the
configuration settings (including all settings on all further tabs) can be
opened and saved.
see also chapter 14.7 Prototype File
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6.2.1 Country Tab
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Chapter 6 - Calculation
6.2.2 General Tab
6.2.2
General Tab
6
Sound sources, whose contribution to the sound immission at the receiver
point is negligible, will be ignored in the calculation if the overall error
induced by this simplification is not larger than the defined value. Therefore,
the larger the maximum permissible error in the final result, the shorter the
time required for the calculation.
max. Error (dB)
In order to verify which sources can be ignored for a given maximum error,
CadnaA applies the following procedure:
Procedure
•
•
•
calculation of the partial levels of all sources based on the geometrical
divergence only (e.g. Adiv of ISO 9613-2),
sorting of the sources according to their partial levels,
For example, with a maximum error of 1 dB, all sources that contribute
less than this amount to the total sum level will be ignored.
This calculation procedure occurs in two steps.
The following examples have a grid of 50*50=2500 point sources with an Aweighted sound power level of PWL=100 dB(A) each. The rays of the sources considered in calculation and the result levels are displayed for maximum
errors of 0, 1 and 2 dB.
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Example
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Chapter 6 - Calculation
6.2.2 General Tab
 Examples\06_Configuration\General\max_error
max. Error 0 dB
resulting level 73.8
dB(A)
All sources are
taken into account
(2500 rays).
6
max. Error 1 dB
resulting level 73.6
dB(A)
There are 2049
sources taken into
account.
max. Error 2 dB
resulting level 73.2
dB(A)
There are 1657
sources taken into
account.
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Chapter 6 - Calculation
6.2.2 General Tab
From the calculation results it can be seen that the level difference compared
with the resulting level at a maximum error of 0 dB is usually less than half of
the error entered:
maximum error
dB(A)
resulting level
dB(A)
difference
dB
0
73.8
0
1
73.6
0.2
2
73.2
0.6
5
71.7
2.1
6
This difference is due to just considering of the geometric divergence Adiv
when estimating the contribution of each source. Within the final calculation,
however, further attenuation terms besides Adiv contribute to the overall
attenuation reducing the effect on the resulting level.
For expertise work (e.g. noise assessments for legal planning permissions and
official approvals) a maximum error of 0 dB shall be used. For noise mapping
or other major scenarios, a maximum error of 0 or 1 dB may be useful to reduce the computation time without sacrificing accuracy.

The partial level of sources not considered in the calculation due to the
maximum error are not listed on the table Partial Level of a receiver
and not in the menu Tables|Partial Level (see chapter 5.1.2 and
14.3.2).

Furthermore, the sources not considered are also not included in the
calculation protocol (see chapter 6.5).
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Chapter 6 - Calculation
6.2.2 General Tab
max. Search Radius
(m)
By the search radius, a circle is defined around the receiver point. Just the
sources inside this circle will be considered in the calculation.
Example
The following examples show that just sources smaller than the search contribute to the receiver level.
 Examples\06_Configuration\General\max_search_radius
search radius
300 m
6
search radius
500 m
Default Value
The default search radius is 2000 m. Depending on the project-specific
conditions, a smaller or a larger radius may be useful. A small radius will
reduce the calculation time, but may cause that dominant sources outside the
search radius may not contribute. By a large search radius more or less all
sources are included, but at the expense of a large computation time required
without gaining any additional accuracy.
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6.2.2 General Tab
6 39
A general value being useful for all kinds of scenarios cannot be given. The
table below provides, however, some typical search radii for different
scenarios:
Scenario
Typical Search Radius,
value or value range (m)
receivers close to source/s
(industry, road, railway)
2000
city center with numerous sources
(roads)
500
rural areas
with a few main roads
5000
large-scale
noise mapping projects
2000 to 5000
In any case, the radius shall be increased when loud and presumably
dominant sources are located outside of the existing search radius causing
level jumps (e.g. with the default search radius of 2000 m). Level jumps
caused by single, dominant noise sources can be more easily revealed using
the noise grid than being caused by numerous, spatially distributed sources.
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Chapter 6 - Calculation
6.2.2 General Tab
Min. Distance Source
to Receiver
The minimum distance source-receiver enables to suppress the calculation of
propagation near the source. Within this vicinity of the source the same total
attenuation as calculated at the minimum distance specified is used causing
no increase in overall attenuation with distance in this area.
Example
The following example shows the grid appearance for the minimum
distances of 0 and 20 m along a road.
 Examples\06_Configuration\General\min_distance_source_rcvr
minimum distance source to receiver
0m
(default setting)
noise contours reach to the emission
lines of the source (here: road)
minimum distance source to receiver
20 m
noise contours start from minimum
distance (here in steps of 1 dB)
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Chapter 6 - Calculation
6.2.2 General Tab
In CadnaA you also have the possibility to evaluate the accuracy of noise
prediction. This accuracy depends on the accuracy of the emission values
used and the accuracy resulting from the calculation of propagation.
Uncertainty
In addition to the uncertainty of the emission data the uncertainty of the
propagation can be taken into account (as e.g. caused by varying
meteorological conditions). Enter an expression into the input box
„Propagation Coefficient Uncertainty“.
Propagation Coefficient
Uncertainty
Examples for expressions:
Expression
Remarks
3 dB
global correction,
i.e. no increase with distance d
3*log10(d/10)
uncertainty depending on distance,
uncertainty is 3 dB at 10 m distance,
reference distance d0=10 m
(Default)
max(1, 2*log10(d/1)-3)
based on a legal act when predicting the
noise impact from wind turbines in the
German state of Brandenburg,
reference distance d0=1 m
In addition to the operators (see chapter in CadnaA manual „Attributes,
Variables, and Keywords“) the following additional attributes are available:
•
d: 3D-distance source-receiver
•
d2: 2D-distance source-receiver
plus all further operators for expressions available in CadnaA.

By default, the calculated sound levels are not altered just by specifying
a standard deviation Sigma or a propagation coefficient uncertainty.
This requires to select or enter a suitable parameter or expression on tab
„Evaluation Parameter“ (see chapter 6.2.5).
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Available Abbreviations
42
6
Standard Deviation
Sigma
Chapter 6 - Calculation
6.2.2 General Tab
The source-specific uncertainty is specified by entering a standard deviation
Sigma (dB) on the dialog Memo Window of each individual source. In case
the sound power level of the source has been measured, the standard
deviation for grades 1, 2 or 3 can be used (according to ISO 3740 series).
6
Dialog Memo-Window (accessible via each source dialog)
Make sure that at least one of the evaluation parameters SigmaD/SigmaE/
SigmaN (for Day|Evening|Night) on the tab „Evaluation Parameter“ has
been selected. The calculation of the Sigma values for single receiver (see
chapter 5.3) occurs using the command Calculation|Calc or by clicking on
the calculator symbol on the toolbar. The results are displayed on the dialog
Receiver or on the Result Table (see chapter 11.2). The distribution of the
uncertainty can be displayed as well on the grid resulting from a grid
calculation (menu Grid|Calc Grid, see chapter 5.3).
 Samples\Infos\Uncertainty.pdf
In /97/ it is shown how to evaluate the uncertainty of levels based on the uncertainty of sources and the uncertainty of propagation. The procedure using
the data structure as implemented in CadnaA is demonstrated by an
example.
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Chapter 6 - Calculation
6.2.2 General Tab
This option enables a seamless transition of the grid - regardless of the type
of appearance selected (see chapter 5.3.2) - to the borders of closed polygons
(such as of object types „Building“, „Area Source“, and „Parking Lot“). This
is accomplished by interpolating the grid level values up to the first grid point
inside polygon area. When calculating the levels at these grid points, the
screening effect by the actual obstacle is not considered (i.e. an extrapolation
of the free-field level occurs). This option is enabled by default.
Extrapolate Grid
’under’ Buildings
Examples
 Examples\06_Configuration\General\extrapolate_grid
option activated:
extrapolation occurs up to the
1st grid point laying inside the building
option activated:
as before, with transparent
building and with grid values
option deactivated:
white gaps outside the building are due
to the next grid point laying inside the
building
option deactivated:
as before, with transparent
building and with grid values
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Chapter 6 - Calculation
6.2.2 General Tab
It is recommended to deactivated the option „Extrapolate Grid ’under’
Buildings“ with the grid appearance option „Lines of Equal Sound Level“ selected in conjunction with the activated option „Exclude Buildings“ on menu
Grid|Specifications|Options (see chapter 5.3.1).
6
Calculation of Terrain
Height
With the option „Extrapolate Grid ’under’ Building“ activated this also
applies to the calculated terrain height level at each grid point
Vertical Grid
This option has no effect at vertical grids, i.e. there is no extrapolation of the
grid calculated in the vertical plane grid in front of the facade the building’s
interior area. Therefore, lower levels may be displayed - in particular with grid
appearance options „Lines of Equal Sound Level“ and „Areas of Equal
Sound Level“ - on the vertical grid in front of a facade grid due to the missing extrapolation to the building’s interior.
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Chapter 6 - Calculation
6.2.2 General Tab
If this option with the setting n*n is selected, the level calculation occurs
starting at each of the (n+1) grid points as specified on menu Grid|
Specification and at the center point of each rectangle delimited by those
four points.
Grid Interpolation
6
Option "Grid Interpolation": approach when the transition
from a rectangle of size 9*9 to size 5*5 occurs
If either of the following conditions are not met for each rectangle delimited
by the four calculated points, this rectangle is subdivided into four equal
squares and the check is repeated for each of these new four rectangles. If any
of these conditions is still not met, a further subdivision occurs recursively
until, in the end, the conditions are met or all grid points have been taken into
account in the calculation based on the grid specification.
The conditions are:
1.
The difference between the largest and the smallest level calculated at
the four corners of the rectangle is, at most, equal with the specified
maximum value (default value: 10 dB).

The default value of 10 dB ensures that - in case of significant extra
attenuation between the corners (e.g. by large obstacles) - a further
subdivision occurs.
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Chapter 6 - Calculation
6.2.2 General Tab
2.
The mean level calculated from the levels at the two corner points of
each diagonal shall not differ from the level at the center point by more
than the specified maximum deviation (default value: 0.1 dB). This condition must be fulfilled for both diagonals.

The default value of 0.1 dB is - in general - exceeded if additional attenuations on the diagonals between the corners and the center are caused,
e.g. by a screening obstacle.
When these conditions are fulfilled, the interpolated values inside the
rectangle match sufficiently with the real values and the levels at the remaining grid points inside the rectangle are interpolated from the levels calculated
at the four corner points.
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Chapter 6 - Calculation
6.2.2 General Tab
When selecting this option, an approximative method for the screening
calculation when using RLS90 or Schall03 (1990) is applied causing an
acceleration of the screening calculation. In this case, however, the
calculation applied is longer compliant with those guidelines.

Fast Screening
Do not use this option with other calculation standards or source types
(in particular not with point, line and area sources) as this may cause
irregular results.
By this procedure, no detailed calculation by scanning each for each obstacle
in the ray’s path occurs, but a given parabolic ray path is used. Only those
buildings exceeding this path will contribute to the screening effect while the
others are not even checked for.
In the vertical cross-section (see chapter 9.12) only those obstacles are shown
contributing to the screening effect. Those not being intersected by the ray
path are not displayed.
"fast screening" activated: On the sectional view of a ray
only a limited number of obstacles are displayed
(detailed section near the source).
"fast screening" deactivated: On the sectional view of a ray
all obstacles are displayed as all are included in the screening calculation
(detailed section near the source)
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Chapter 6 - Calculation
6.2.2 General Tab
Calculation Strategies
There are two kinds of calculation strategies applied in noise prediction software, the ray-tracing method or the angle scanning method. CadnaA is the
only software program offering both methods. The ray-tracing method is
used in CadnaA by default.
Ray Tracing (RT)
The ray paths between sources and receivers are constructed in a
deterministic way. Extended sources are subdivided dynamically applying the
projection method. The source segments represented by a single ray are
shorter at small receiver distances and large at large receiver distances.
Screening objects and all gaps between them produce at least one single ray
(see also chapter 6.1.3). With the option „Angle Scan Method“ deactivated
(see below) the ray-tracing method is used.
6
Ray-Tracing with projection to subdivide
extended sources dynamically
Angle Scanning (AS)
With the option „Angle Scan Method“ activated the procedure described in
the following will be used. In this case, the calculation of the receiving levels
is carried out using rays emitted at constant angular steps, starting from the
receiver point to the source. Only those objects intersected by the ray’s path
contribute to the screening effect. Point sources situated within the angle
cone are virtually transferred to the ray’s path.
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Chapter 6 - Calculation
6.2.2 General Tab
6
Angle Scanning Method: Rays start from the receiver
and are spaced at equal angular steps
•
Number of Angle Segments: default value 100, resulting in 360°/
100=3.6° steps between rays
•
Reflection depth: With a reflection depth of zero, obstacles behind the
first reflector in direction of the ray are not seen, irrespective of the
reflection order specified and when the first reflector detected was not
reflective, based on its dimensions. Thus, the specification of the reflection depth represents the number of potential reflectors which can be
ignored in ray direction because of their dimensions. However, at least a
single additional reflector is taken into account in any case.
Example: In order to detect reflector no. 4, a reflection depth of at least 3
must be specified.

With the option „Angle Scan Method“ activated the settings on the
„Partition“ tab are no longer relevant (see chapter 6.2.3).
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Mithra Compatibility
Chapter 6 - Calculation
6.2.2 General Tab
When the option „Mithra Compatibility“ is activated, all the approximations
used in the software Mithra are also used in CadnaA-Mithra. This is the
mode that should be used to load MITHRA projects using CadnaA-Mithra
and to obtain the same as with MITHRA.

6
The check box is only available if the option CadnaA-Mithra has been
purchased.
Within the MITHRA compatible calculation - among others - additional
screening will be taken into account, see the barriers with special crowning in
CadnaA-Mithra (see chapter 3.2.2).
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Chapter 6 - Calculation
6.2.3 Partition Tab
6.2.3
Partition Tab
6
At line and area sources, the largest dimension of a section Hmax generated by
segmentation is smaller than the raster factor multiplied with the distance d
of the center point of the section from the receiver. A raster factor of 0.5 is
used per default:
Raster Factor
Hmax < 0.5 * d
The smaller this factor, the more sub-segments of the source/s are generated
and the more computation time is required.
Upon calculation the software checks, based on shortest distance between a
receiver (or a grid point) and any source, whether the entered geometry of
each source section respects the defined segmentation rule. If not, the corresponding source section is halved and the check is repeated. This continues
until the defined segmentation rule is respected.
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 Examples\06_Configuration\Partition\raster_factor
Chapter 6 - Calculation
6.2.3 Partition Tab
The following example shows the segmentation of a line source of 200 m
length using two different raster factors for a receiver at a perpendicular distance of 100 meters from the center of the source.
Raster Factor
0.5
6
The required
segment length
is respected
with four
segments
because it holds:
50 m < 125/2
m
or resp.
50 m < 103.1/2
m
Raster Factor
0.1
The required
segment length
causes three or
four division
steps resp.:
- for the 6.25 m
segments:
6.25 m < 100/
10 m or
6.25 m < 123.2/
10 m
- for the 12.5 m
segments:
12.5 m < 128.8/
10 m or
12.5 m < 137.1/
10 m
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Chapter 6 - Calculation
6.2.3 Partition Tab
The maximum and minimum section length (in meters) resulting from the
automatic segmentation can be specified. The entered values serve as an additional criterion besides the grid factor. By the segmentation method, no
larger source segments as the maximum section length and no smaller than
the minimum segment length produced.
Maximum/Minimum
Length of Section (m)
The following examples use a raster factor of 0.5.
 Examples\06_Configuration\Partition\max_section_length
maximum
length of
section 1000 m
(default value):
In this example
without any
effect as all segment lengths are
< 1000 m.
maximum
length of
section 25 m:
All source
segments have
segment lengths
smaller than 25
m. Smaller section lengths
arise depending
on the raster
factor.
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Minimum Length of
Section (%)
Chapter 6 - Calculation
6.2.3 Partition Tab
The minimum section length can also get specified as a percentage of the total length. If the minimum segment length is not 0% the higher value of
„Min. Length of Section (m)“ and „Min. Length of Section (%)“ is used.

 Examples\06_Config6
uration\Partition\min_section_length
Specifying a percentage can speed up the calculation considerably, as
with extended and large-area sources less rays from sub-segments are
produced.
The subsequent examples use a grid factor of 0.5 and a maximum section
length of 1000 m.
minimum section length 1 m (default) and 0%: There are 14 source segments generated
with the section lengths 125, 62.5 and 31.25 m.
minimum section length 100 m and 0%: There are 12 source segments generated
with the section lengths 125 and 62.50 m. The four sections having a length of
31.25 m have been replaced by two sections with a length of 62.50 m in order
to fulfill the condition: 62.5 m < 100 m.
Partition according to
RBLärm-92, Proc. 1
The procedure 1 is the so-called "precise" method according to /20/ yielding
sections as long as possible.

This option is just relevant to German road noise assessments.
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Chapter 6 - Calculation
6.2.3 Partition Tab
With the option „Projection“ activated, prior to the segmentation of sources,
a pre-partitioning for line and area sources occurs subdividing the source into
screened and unscreened parts. After this subdivision the screened and unscreened parts of source are segmented separately based on the distance criterion (see chapter 6.1.3).
Projection of
With this option, even the terrain being modeled from terrain contours is
considered within the projection procedure of line and area sources. This option is disabled by default.
Projection at Terrain
Model
When this option is enabled the terrain contour lines resulting from the
triangulation are ignored when deciding which terrain contours provide
screening or not.
6
 Examples\06_Configuration\Partition\projection_DTM
Projection at Terrain Model OFF: The screening of the line source line by the ter-
rain (with a top edge at 20 m height) is not considered the projection.
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Chapter 6 - Calculation
6.2.3 Partition Tab
6
Projection at Terrain Model ON: In the projection, the part of the
line source shielded by the terrain (orange rays) is segmented
separately from the non-screened part.
Maximum Distance
Source-Receiver
If the receiver point is further away than this maximum distance no projection is applied (default distance: 2000 m).
Search Radius Source
When partitioning sources using the projection only obstacles which are
taken into account within this distance from the source (default radius: 100
m).
Search Radius Receiver
When partitioning sources using the projection only obstacles which are
taken into account within this distance from the receiver (default radius: 100
m).
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Chapter 6 - Calculation
6.2.3 Partition Tab
With activation of this option the projection method will not generate smaller
sections as specified for the „Min. Length of Section“. The larger value of
„Min. Length of Section (m)“ and „Min. Length of Section (%)“ will be used.

6 57
Min. Lengths are
considered by projection
Activating this option can accelerate the computation.
 Examples\06_Configuration\Partition\min_section_length_projection
6
option „Min. Lengths are considered by projection“ ON
option „Min. Lengths are considered by projection“ OFF: The rays in orange color
shown above do not occur with the option activated.
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6.2.3 Partition Tab
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Chapter 6 - Calculation
6.2.4 Reference Time Tab
6.2.4
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Reference Time Tab
6
The reference time specifies the time interval for the calculation of the
average sound pressure level considering the actual operating time of the
source with respect to the basic evaluation requirements.
The specification of a reference period is always required when the emission
from different periods Day/Evening (Recreation Time)/Night D/E/N shall
be combined to a mixed evaluation level (e.g. Lden, Lde).
In general, penalties for noise-sensitive daily periods are used to account for
the increased noise effect (annoyance) when calculating such mixed evaluation levels.
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Penalties
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Chapter 6 - Calculation
6.2.4 Reference Time Tab
Dialog Options
Allocation
Hours - Periods
On the upper part of the „Reference Time“ tab the 24 daily hours are
allocated to the periods. Each hour can be assigned to one of the daily
periods Day/Evening (Recreation Time)/Night by entering a letter (D, E or
N, uppercase or lowercase).
This flexible concept enables to meet all the requirements of the EC
Environmental Noise Directive (also when possibly shortening the Night period and the lengthening the Day and/or Night period).
6
If individual hours are not to be taken into account, the relevant box can be
left blank (see examples below).
The reference periods defined apply to all noise types and affect the mixed
evaluation levels such Lden and Lde (see chapter 6.2.5). For the non-mixed
evaluation levels (such as Ld, Le and Ln) no time correction and no penalty is
considered.
The following rules apply depending on the different noise types:
•
industrial sources: The reference periods will be considered only when on
the source dialog the option „Operating Time (min)“ has been selected
with operating times specified or when diurnal pattern has been selected
(see chapter 2.1.1).
•
road: Depending on the selected calculation standard the receiving level is
just calculated for day and night only. In order to perform calculations
involving the allocation of hours (e.g. for the EC Environmental Noise
Directive) diurnal patterns for roads have to be used - if the selected road
noise standard does not provide traffic volumes for the periods D/E/N
distinctively (see chapter 2.4, for each road standard, and chapter 6.2.10).
•
railroad: as with road, applying the option „Use Non-Standard Reference
Time D/E/N“ (see chapter 2.6, for railway standard, and chapter 6.2.11).
•
aircraft noise: see railroad (for „Aircraft Noise“ tab see manual FLG)
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Chapter 6 - Calculation
6.2.4 Reference Time Tab

The calculation of the noise indicators Lden and Ln according to the EC
Environmental Noise Directive is possible with the standard version of
CadnaA. By contrast, the evaluation of noise levels statistics with
respect to the number of exposed inhabitants requires the evaluation
method „Object-Scan“ provided by the CadnaA option X or XL.
Penalties are only taken into account for mixed evaluation parameters, such
as Lden or Lde. Enter the required penalties according to the applying legal requirements. For example, according to the definition of Lden enter penalties
for the period „Evening/Recr. Time Penalty“ of 5 dB and for the period
„Night“ of 10 dB.
Penalties

Recreation Time Penalty
only for
This option refers the a specific part of German legislation requiring to
apply the recreation time penalty only to „general“ and „pure“
residential areas, but not for mixed or industrial areas. In contrary, this
option is on most or all other countries no required and has to be deactivated.
If this option is activated, select the types of land use for which recreation
time penalty shall be considered. This selection requires that
•
objects „Area of designated Land Use“ have been entered in the project
and a type of land use therein has been selected, or
•
receivers have been entered with a type of land use assigned.
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Chapter 6 - Calculation
6.2.4 Reference Time Tab
Examples for Reference
Times & Penalties
No
Settings on „Reference Time“ tab
1
6
plus: land use type specific recreation time penalty activated
Remarks
To consider the loudest hour during the night
only one letter N is entered in the allocation of
hours. In this case, the operation time entered
during the night is the operating time (min) of
the source during this single hour.
For the periods „Day“ and „Evening/Recreation
Time“ the operating time refers to the reference
times 13 h D (= 960 min) and 3 h E (= 180 min).
The penalty for „Evening/Recreation Time“ is 6
dB. The surcharge 10 dB for Night is irrelevant
since there is mixed level be used combining the
night period; the evaluation parameters are Lde
and Ln.
2
Alternatively, in order to determine the loudest
hour during the night, the letter N is entered for
all hours of the night and the evaluation
parameter L1hMaxN is selected (see chapter
6.2.5).
This requires, however, that for each relevant
industrial source a specific diurnal pattern is
defined and addressed via the source‘s
dialog.
The further settings are as for No.1; the
evaluation parameters are Lde and L1hMaxN.
3
In order to perform calculations according to the
EC Environmental Noise Directive the following
allocation of hours is assumed: 12 h D (starting at
6 o‘clock), 4 h E (starting at 18 o‘clock) and 8 h
N (starting at 22 o‘clock).
The penalties are 5 dB for „Evening (Recreation
Time)“ and 10 dB for „Night“.
Both penalties are relevant when calculating the
day-evening-night noise index Lden, not however, for the night-time noise index Ln.
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Chapter 6 - Calculation
6.2.4 Reference Time Tab
No
„Reference Time“ tab
4
5
Remarks
similar to No. 3, but the Day period has been
extended to 14 hours (from 6 to 20 o‘clock).
The extended Day period does not receive a penalty when calculating Lden.
The shortening of the Evening period by 2 hours
and the corresponding lengthening of the Day
period corresponds with the provisions of the
EC Environmental Noise Directive (/121/,
Annex I).
In case source-specific operating times are used,
those - as before - refer to the above mentioned
periods.
The allocation of hours just uses the letters D
and N. Thus, an Evening period does not exist.
The mixed level Ldn is assessed by adding a penalty of 10 dB for „Night“. Further, the Night
level Ln calculated.
The specified penalty for „Evening/Recreation
Time“ of 5 dB is irrelevant.
Regarding the option „Special Reference Times for Industry (min)“ on the
„Reference Time“ tab of former releases of CadnaA see chapter 6.3.
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configuration
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Chapter 6 - Calculation
6.2.4 Reference Time Tab
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Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
6.2.5
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Evaluation Parameters Tab
6
CadnaA offers a flexible approach to define the evaluation parameters to be
calculated, such as individual levels (e.g. Ld, Ln) or level for combined periods
(e.g. Lden, Lde), the uncertainty Sigma (for Day/Evening/Night) or for userdefined expressions. The following evaluation parameters can be selected by
default:
•
•
•
•
levels for individual daily periods D/E/N: Ld, Le, Ln
levels for combined daily periods: Lden, Lde, Len, Ldn
uncertainty for daily periods D/E/N: SigmaD, SigmaE, SigmaN
loudest hourly level in the daily periods D/E/N: L1hMaxD, L1hMaxE,
L1hMaxN
and
•
formula expression „=f(x)“: total level or noise-type specific level, Day/
Evening/Night, single value or spectrum, total or in octaves, linear/A-/
B-/C- or D-weighted.
Formula expressions can be defined using the CadnaA specific operators
(see chapter 1.1 in the manual „Attributes, Variables, and Keywords“).
Furthermore, the following aircraft noise specific levels and evaluation
parameters are available (requires option FLG):
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Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
•
•
•
•
•
6
the number of events (e.g. flight movements) above a threshold level:
NATd, NATe, NATn,
the uncertainty for the number of events (e.g. flight movements) above a
threshold level: SigmaNATd, SigmaNATe, SigmaNATn,
the resulting level of the maximum level evaluation for aircraft noise: FlgStatD/E/N,
the standard deviations of the resulting level of the maximum level evaluation for aircraft noise: SigFlgStatD/E/N, and
the so-called „effect related substitute level“ (see chapter 6.6.1) according
to the VDI guideline 3722-2 /44/ for the evaluation parameters Lden
(DEN) and Ln (Night).
As long as no formula expression f(x) is used to exclude certain noise types
from calculation all selected evaluation parameters are calculated including all
types of sources, provided these sources are active. The result levels are
calculated for up to evaluation parameters at individual receivers or facade
points (using the building evaluation symbol), as well as on the horizontal or
vertical grids (besides the ground).
Dialog Options
List Box „Type“
Select from the list box „Type“ the evaluation parameter to calculate. In dialogs and tables showing calculation results (e.g. on the dialog Receiver) up to
four evaluation parameters are displayed.
•
Example: The evaluation parameter for calculation according to the EU
Environmental Noise Directive are the day-evening-night index Lden and
the night index Ln.
In formulas or expressions that attribute names LP1 to LP4 are used for establishing a reference to the evaluation parameters (see chapter 1.1 in the
manual „Attributes, Variables, and Keywords“).
By default, the daytime level Ld and the nighttime level Ln are set.
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Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
After activation of the input box „Name“ a user-defined expression (alias
name) can be entered for the selected evaluation parameter (e.g. „Day“)
which will be displayed instead of the name selected on the list box „Type“.
Input Box „Name“
List box „Type“ with parameter Lde selected,
and activated field Name with an entered user-defined alias „Day“.
6
Dialog Receiver showing three evaluation parameters,
for LP1 an alias name has been entered
Additionally in the box „Unit“ you may enter an identifying item (e.g. dB(A)
or sigma) which will also be displayed if the check box is activated.
After activation an appropriate unit can be entered, being used for display
that also appears in dialogs and tables showing results. Otherwise, „dB“ is
displayed for unit.
In particular, this option is useful in conjunction with a formula expression
f(x) (see below), since by a formula any kind of result can be generated, the
unit of which is not necessarily more expressed in decibels.
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Input Box „Expression“
Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
After selecting the formula symbol „=f(x)“ from the list box „Type“ a userdefined formula expression or a predefined expressions (see double arrow
) can be selected or entered. In formula expressions the CadnaA specific
operators can be used (see chapter 1.1 in the manual „Attributes, Variables,
and Keywords").
By the expression „indd“ the A-weighted noise level Ld
will be calculated just for industry sources.
6
Clicking the double arrow opens a cascading list of predefined expressions.
Select the corresponding parameter from the list.
Error Condition
In case an error occurs within a user-defined expression the value -88 will
result for that evaluation parameter.
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Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
•
The selections „Single Value“ and „Loudest Hour“ include all active
sources or all active sources of a source group, with non-spectral and
spectral emission.
•
By contrast, the selections „Spectrum|Total (linear//A-/B-/C-/Dweighted)“ include the active sources or the active sources of a source
group with spectral emission only.

Both notes above cause that when having non-spectral and spectral
sources in a project, a level difference occurs between the two abovementioned selections (e.g. between the A-weighted sum level as „Single
Value“ (totd) and the A-weighted sum level of the spectral sources only
(„Spectrum|Total|A-weighted“, totd_a).
•
In case a mixed level shall be used as an evaluation parameter (e.g.
„Lden+3 dB“ or „Lde_road-3dB“), it is always required to enter the
entire formula because mixed levels are not available as predefined
expressions.
•
Conditions can be used in expressions (operator „iif“ as IF..THEN..ELSE
loop; see the subsequent example section). Note that just numerical
expressions may be used in formulas. In particular, no strings can be used
in a condition or as a result of a condition.
•
Use just the parenthesis „()“ to define nested expressions. Other types of
brackets meet the error condition.
•
In order to separate variables in expressions just use the comma. Other
separators (e.g. the semicolon) meet the error condition.
•
Extra spaces within expressions are harmless and do not meet the error
condition. By contrast no spaces are allowed between an operator and its
opening parenthesis [thus „iif(...), not „iif_(...) with „_“ representing the
space].
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Notes for user-defined
expressions
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Chapter 6 - Calculation
6.2.5 Evaluation Parameters Tab
Examples for expressions
6
Expression
Remarks
totd+3
addition of 3 dB to the total level Day
strd++schd
energetic summation of level Road Day and level Railroad
Day
totn_2l++totn_3l++totn_4l
energetic summation of the linear total octave level from
125, 250 and 500 Hz (octave-No. 2, 3 and 4)
indd-strd
level difference between the level Industry Day and Road
Day
totd+1.65*sigmad
upper limit of the Daytime-level at 95% single-sided confidence interval („level that is not exceeded at a statistical confidence level of 95%“)
iif(totd>50, totd, 0)
if the total level Day > 50 dB it will be displayed, otherwise
zero
iif(totd>50, 0, totd)
if the total level Day > 50 dB zero, otherwise the total level
Day will be displayed
flgd + 3*sigmad
aircraft noise level Day + 3 * standard deviation Day
flgn + 3*sigman
aircraft noise level Night + 3 * standard deviation Nigh
natn + 3*sigmanatn
number of exceedances of the threshold level for aircraft
noise Night + 3 * standard deviation of the number of
exceedances Night
NOTE - The threshold level for NATs (dB) is specified on
the „Aircraft“ tab.
Adjusting the
configuration
Regarding the option „Compatibility Mode for Industry“ on the „Evaluation
Parameters“ tab of former releases of CadnaA see chapter 6.3.
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Chapter 6 - Calculation
6.2.6 DTM Digital Terrain Model Tab
6.2.6
DTM Digital Terrain Model Tab
6
The standard height defines the absolute terrain height to be used in the calculation when no other information of the actual terrain height is available.
This applies to areas in the model which are not covered by distinct contour
lines or height points (for example, at the corners of the limits, see chapter
9.1). Based on this standard height and the terrain model all objects having a
relative height get assigned an absolute height. The predefined standard
height is 0.00 m.
Standard Height (m)
The following options for the generation of terrain models are available:
Model of Terrain
By triangulation a terrain model consisting of triangles is generated from the
entered height points (see chapter 4.1.2) and the polygon points of terrain
contours (see chapter 4.1.1) and lines of fault (see chapter 4.1.3), if any. In
this case, no ground grid needs to be calculated in order to display the terrain
shape in the 3D-Special view (see chapter 9.14).
Triangulation
The triangulation is the contemporary used method to generate a digital terrain model.
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Chapter 6 - Calculation
6.2.6 DTM Digital Terrain Model Tab
Explicit Edges Only
When activating the option „Explicit Edges Only“, only the entered terrain
contours will cause a screening effect and not the terrain edges resulting from
triangulation. This option has no effect on the 3D-Special view.
Objects with ’Ground at
every point’ influence
DTM
Activating this option will cause the height of the base point of objects with a
height using the option “absolute Height/Ground at every Point“ will determine the terrain height at that location upon triangulation.

6
The options „Search Contour Lines (Average)“ and „Search Contour
Lines (Local Inclined Plane)“ were available in former versions of
CadnaA - before the triangulation method was introduced. These
options are kept primarily for reasons of backward compatibility ans
should not be used for new projects.
Search Contour Lines
(Average)
This option generates a terrain model by assessing the contour lines
regarding the squared distance and by averaging.
Search Contour Lines
(Local Inclined Plane)
This option approximates a terrain model by inserting planes between the existing terrain contours and height points.
Search Radius for
Contour Lines (m)
In order to determine the local terrain height, all terrain contours within this
radius will be considered. The larger the search radius, the longer the calculation time will be.
Displaying triangulated terrain contours
The terrain contours resulting from triangulation can be displayed. Select the
command Properties from the Options menu. Specify a line type for the
object type „Triangulation“ on dialog Appearance (see chapter 9.5).
By default, triangulated lines are not displayed.
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Chapter 6 - Calculation
6.2.6 DTM Digital Terrain Model Tab
Normally, the triangulation method generates a terrain model which leads to
realistic approximations of the terrain at locations between the existing terrain contours and height points. The terrain contours resulting from the triangulation cause a screening effect in the calculation by default. With the
option „Objects with ’Ground at every point’ influence DTM“ activated, also
these objects determine the local terrain height and thus the position of the
resulting edges of the triangles.
General information
on terrain models
The closeness to reality of a numerically generated terrain model applying the
triangulation method depends also on a sufficiently dense sequence of terrain
contours and height points. With too large distances between points defining
the height, cause a relatively coarse terrain model results with large triangles,
each being a plane surface.
6
for more information see Chapter 4 - Topography
With this option enabled, the height of sources which are below ground level
is lifted to a relative height of 0 m within the calculation. This holds for line
and area sources as well, causing the sub-sources resulting from segmentation
to be raised to a relative height of 0 m. With traffic sources (road, railway and
parking lot) the absolute height of the sub-sources is increased by the source
height specified by the respective standard or guideline (for example, by the
source height of 0.5 m for RLS-90 and 0.6 m for Schall 03). In any case, the
(absolute) height used in the calculation is listed on the protocol of receivers
(see chapter 6.5). The specified object height and the terrain model itself will
remain unchanged.
It is recommended to use this global option after importing digital data from
external data sources only. In general, any inconsistencies between the
object’s geometry data and the terrain model shall be avoided by checking the
project thoroughly.
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Ground’ to GroundNiveau
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Area sources with
constant relative
height follow terrain
6
Chapter 6 - Calculation
6.2.6 DTM Digital Terrain Model Tab
With this option enabled, the geometry of area sources and parking lots will
be split into triangles according to the entered triangulated terrain contour
lines. The new object geometry is displayed on the 3D-Special view.
Regardless of whether the sound power level PWL or the area related sound
power level PWL“ is specified as emission data in the source dialog, the resulting value of the not specified emission level is based on the total area of
the 3D-surfaces of all fitted triangles. This sum does not match the 2D-area
displayed on dialog Polygon:Geometry of the source, as this is the projected
area.
Example
option deactivated: The parking lot is
covered by the terrain as the parking lot’s
polygon is outside the terrain contours.
option activated: The parking lot is fitted to
the terrain’s shape.
In the example above, the command „Fit Object to DTM“ from the parking
lot’s context menu (see chapter 11.24 in the manual „Introduction to
CadnaA“) would not cause any effect, because the parking lot’s polygon does
not intersect with any of the entered or triangulated terrain contour lines.
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Chapter 6 - Calculation
6.2.7 Ground Absorption Tab
6.2.7
Ground Absorption Tab
6
When calculating the ground absorption the global ground absorption for areas not covered by the object "Ground Absorption" (see chapter 3.4) can be
defined here (0 <= G <= 1). By default, a value of G=1 is assumed (porous
soil).
Default Ground
Absorption G
It can be selected whether the map of ground absorption shall be used or
not. This option is useful when having numerous areas of ground absorption
in the project. In this case, the map of ground absorption accelerates the calculation because this map is used instead of the list of areas. The following
options are available:
Use map of ground
absorption
•
•
•
•
No: The existing areas of ground absorption are used within the
calculation.
Yes: The map of ground absorption is used in any case.
Automatic (Default): Provided that all ground absorption areas in the project have more than 100 polygon points the map of ground absorption is
generated and used. Otherwise the areas of ground absorption are used.
Resolution (m): resolution of the ground absorption grid (default value: 2
m)
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Chapter 6 - Calculation
6.2.7 Ground Absorption Tab
Roads/Parking Lots
are reflecting (G==0)
With this option activated, the road region (road width plus additional width
(from dialog Appearance), or additional width from self-screening) will be
considered as globally reflecting in the calculation. Whether this setting has
any effect depends on the selected calculation standard or guideline.
Buildings are reflecting (G==0)
With this option activated, the base area of buildings (road width plus
additional width (from dialog Appearance), or additional width from selfscreening) will be considered as globally reflecting in the calculation. Whether
this setting has any effect depends on the selected calculation standard or
guideline.
Railways are absorbing (G==1)
With this option activated, the road region (road width plus additional width
(from dialog Appearance), or additional width from self-screening) will be
considered as globally absorbing in the calculation. Whether this setting has
any effect depends on the selected calculation standard or guideline.
6
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Chapter 6 - Calculation
6.2.8 Reflection Tab
6.2.8
6 77
Reflection Tab
6
In order to perform calculations involving reflections, the following settings
are required:
1.
On the „Reflection“ tab (menu Calculation|Configuration), the maximum order of reflection to be calculated is set (non-zero).
2.
Make sure that all objects to be considered in the calculation of reflections (e.g. buildings, barriers, cylinders, 3D-reflectors) are reflective (see
chapter 3.1).
CadnaA calculates reflections applying time-efficient algorithms to detect all
possible ray paths up to the order specified.
However, the required computation time increases with increasing order of
reflection and with increasing number of reflective objects. High reflection
orders used in conjunction with large scenarios may lead to unacceptable
computation times. A calculation of higher orders of reflection should, therefore, only be used with limited scenarios and with a few reflective objects.
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max. Order of Reflection
Chapter 6 - Calculation
6.2.8 Reflection Tab
The maximum order of reflection to be taken into account using the image
source method, basically determines the calculation time. For most tasks it is
sufficient to just consider the first order of reflection. Higher reflection orders should be used only with limited scenarios comprising a fewer number
of objects. Default Setting: 0 Order (direct rays only).

6
Several guidelines and standards for the calculation of road and railway
noise (e.g. RLS-90 /17/ or Schall03 /23/) just consider reflections up
to the first order. When the options „Strictly acc. to RLS-90“ (see chapter 6.2.10) and/or „Strictly acc. to Schall03“ (see chapter 6.2.11) are activated on the „Road“ resp. „Railroad“ tabs, the setting for the reflection
order on the „Reflection“ tab is ignored. In these cases, the calculation
is performed only up to and including the first order.
At present, CadnaA calculates reflections up to a maximum order of 20.
CadnaA offers to display the ray paths contributing to the level at a receiver
(see chapter 6.1.7).
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Chapter 6 - Calculation
6.2.8 Reflection Tab
Conditions for Calculation of Reflection
Up to this distance in meters from the source or from the receiver all the reflective surfaces are detected (default value: 100 m).

Search Radius from
Source/from Receiver
When this input box is empty or when the value is 0, no test for reflective surfaces occurs.
 Examples\06_Configu
setting: up to 1st order,
100 m radius from source
and from receiver:
All barriers which are
located entirely or partially
within the two search radii
have been detected, provided they have reflective
properties and satisfy the
reflection condition.
setting: up to 1st order,
150 m radius from source, 0
m from receiver:
The northerly, reflective
barrier is detected as well.
The easternmost barrier is
outside the search radius of
the source.
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adius_reflector
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Maximum Distance
Source - Receiver
Chapter 6 - Calculation
6.2.8 Reflection Tab
When the receiver is further away from the source than the maximum
distance, no reflections will be calculated. This requirement is checked for in
addition to the specified search radius for source and receiver (default value:
1000 m).
 Examples\06_Configuration\Reflection\max_distance_source-rcvr
6
settings:
- maximum distance source-receiver 1000 meters
- calculation up to 1st order of reflection
- 100 m radius around source and receiver:
The reflector is only seen by the receiver at distance x = 500 m, since there the reflector is
within the 100 m radius around the receiver and less than 1000 m away from the source. By
all the other receivers the reflector is not seen.
settings: as before
The reflector is not seen by the receiver at distance x = 1100 m because it is more than 1000
m away from the source. The reflector is seen by the receiver at x = 999 m, since the latter is
less than 1000 m away from the source and the reflector lays within the search radius of 100
m around the source.
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Chapter 6 - Calculation
6.2.8 Reflection Tab
This option offers to interpolate between the region having been calculated
with and that region having been calculated without reflections. Interpolation
between these regions is particularly useful with grid calculations in order to
avoid level jumps at the border of both regions.
•
The default value is 1000 m. So, no interpolation occurs as there is no
transition region (i.e. the value „Interpolate from“ equals the value „Max.
Distance Source-Receiver“).
•
When the value „Interpolate from“ is less than 1000 m (assuming the
default maximum distance source-receiver of 1000 m) the effect due to
reflection is continuously decreased in the intermediate region.
In the examples the maximum distance source-receiver is 1000 m. All other
settings correspond to the default setting.
value for "Interpolate from" = 1000 m: The level increase due to reflection visible on the
grid in front of the reflecting barrier suddenly ends at a distance of 1000 m (corresponding
to the maximum distance source-receiver of 1000 m).
value for "Interpolate from" = 500 m: In the distance range from 500 to 1000 m from the
source, the level is interpolated linearly, so that no level changes occur on the grid.
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Maximum Distance
Source - Receiver,
Interpolate from
6
 Examples\06_Configuration\Reflection\max_distance_source-rcvr
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Minimum Distance
Receiver - Reflector
Chapter 6 - Calculation
6.2.8 Reflection Tab
When calculating the facade levels at buildings (by using receivers or facade
points in conjunction with the Building Evaluation, see chapter 5.4) national
regulations specify whether these levels have to be calculated including the
reflection by the facade or not.
When the calculation of the facade level does not consider the reflection, the
minimum distance receiver - reflector specified here must to be larger than
the real distance of the receiver or facade point from the building’s facade
surface.
The default value for the minimum distance receiver - reflector is 1 m. This
means that for all receivers and facade points being placed closer to building
facade no reflection is considered in the calculation.
6

With a minimum distance of 0 m reflections will always be calculated,
provided the building has reflective properties.

When using the Object Snap (see chapter 9.3) to place receivers along
facades the „Distance Point-Facade“ must be smaller than the minimum distance specified here in order to not calculate reflections
(default distance: 0.05 m). The same applies regarding the distance of
facade points with Building Evaluations (see chapter 5.4.1, section "Distance Receiver-Facade (m)", default value 0.05 m).
All other reflectors located outside this minimum distance will cause
reflections provided the other configuration settings and the respective
object properties are adequate.
Minimum Distance
Receiver - Reflector,
Interpolate to
Here - in contrast to the maximum distance - a larger value than the
minimum distance can be specified. For the intermediate region, the level values are interpolated linearly (from „none“ to „full“ reflection).

A smaller value than the minimum distance receiver - reflector has no
effect.
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Chapter 6 - Calculation
6.2.8 Reflection Tab
6 83
 Examples\06_Configu
•
for a receiver at 0.05 m distance off the facade:
ration\Reflection\min_dis
tance_rcvr-reflector
6
close-up at the facade’s surface:
minimum distance receiver - reflector: 1 m (default value), receiver at 0.05 meters off the
facade (placed using object snap):
In the region up to 1 m in front of the facade, the levels at receivers, along facades or on the
grid are calculated without reflections (i.e. no ray is reflected by the facade). Outside this
region (distance > 1 m) the facade reflection is taken into account.
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Chapter 6 - Calculation
6.2.8 Reflection Tab
•
for the lines of equal noise level on the grid:
6
minimum distance receiver - reflector 1 m (default value), Interpolate to 1 m (default value):
A level jump occurs at 1 m distance from the facade.
minimum distance receiver - reflector 1 m (default value), Interpolate to 3 m: The level jump
is smoothened by interpolation between 1 and 3 m distance off the facade.
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Chapter 6 - Calculation
6.2.8 Reflection Tab
When modeling of sound radiation from facades (see chapter 6.1 in the manual „Introduction to CadnaA“), the reflection by vertical area sources at the
own building is usually taken into account by the directivity index K0 or D
(see chapter 2.1.1 "Common Input Data", section "K0 without Ground"). In
this case, it has to be prevented for considering reflected rays at the own facade in addition.
The default value for the minimum distance source - reflector is 0.1 m. For a
source located within that distance in front of the facade no reflection at the
rear wall is calculated.

When using the Object Snap (see chapter 9.3) to place vertical area
sources a distance of 0.05 m is applied per default. In conjunction with
the minimum distance source - reflector of 0.1 m this setting ensures
that no reflection at the own building is taken into account.
For all other sources that are laying outside this minimum distance, the building is reflective provided the other configuration settings are adequate.
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Minimum Distance
Source - Reflector
6
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Chapter 6 - Calculation
6.2.8 Reflection Tab
 Examples\06_Configu
ration\Reflection\min_dis
tance_source-reflector
6
minimum distance source - reflector 0.1 m: As the source with a distance of 0.05 m in front of the facade is located closer than the minimum distance, no reflection at the building occurs.
minimum distance source - reflector 0 m: The calculation of reflections at the own house occurs always. In this case, it must be ensured
the directivity index K0 resp. D of the source is set to 0 dB. Otherwise, the reflected component would be considered twice.
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Chapter 6 - Calculation
6.2.9 Industry Tab
6.2.9
6 87
Industry Tab
Information on the calculation options for the following standards or
guidelines for industrial sources can be found in the German version of the
CadnaA-reference manual:
 VDI 2714/2720
 DIN 18055 (1987)
 OEAL 28 (1987)
The options on tab „Industry“ effect the following types of sources:
•
•
•
•
6
point, line, and area sources, vertical/horizontal
(see chapter 2.1.1)
tennis point of serve (see chapter 2.3)
parking lot (see chapter 2.7)
optimizable area source (see chapter 2.9)
The subsequent table lists the main characteristics of the propagation models
for industrial sources as treated in the next chapters explaining the
configuration options. A special focus is put to the type of modeling being
used for the various attenuating effects in sound propagation.
Table „Propagation
Models Industry“
A further table describes the properties of obstacles and special-objects in
CadnaA with each propagation model.
Table „Obstacles and
Special-Objects“

Since for Nord 2000 an external DLL is performing the actual
calculations no details are given in the subsequent tables for that
standard (see chapter 6.2.9.3 "Nord 2000").
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Chapter 6 - Calculation
6.2.9 Industry Tab
Propagation Models Industry
No
6
Option or
Propagation
Effect
Standard / Guideline
ISO 9613 (1996)
Nordic Prediction
Method (1996)
Nord 2000
(using DLL V20)
1
calculation using
A-weighted levels
yes
yes (though not part of
NPM originally)
yes
2
spectral
calculation
yes
(for octaves 63 Hz to 8000 Hz, extended in CadnaA down to 31.5 Hz)
yes, see ISO 9613
yes (spectrum visible
on protocol only)
3
geometrical
attenuation
(divergence)
full sphere (4r2)
see ISO 9613
full sphere (4r2)
4
attenuation by
air absorption
based on the air absorption coefficient accord. to ISO 9613-1
according to NPM,
Annex B
yes
5
handling of ground
reflections
not using image sources, but using an algorithm which includes the correction for ground absorption (see below)
see ISO 9613
using complex
ground impedance
6
handling of
reflections
at obstacles
by image sources with no restriction to the maximum order of reflection,
condition for reflection considers obstacle size compared to wavelength,
sound power of the image source may include absorption coefficient/
reflection loss of the reflector
see ISO 9613, but
separate criteria for minimum length and height
of reflector
yes
7
attenuation due to
ground effect
(ground
attenuation)
2 procedures:
1. general method (spectral): using ground factor G (0<=G<=1), „applicable only to ground which is approximately flat“
2. alternative method (for A-weighted levels): generalized, not using
ground factor G, „for ground surfaces of any shape“
see spectral method of
ISO 9613, but with
height correction when
„significant screening
occurs“
by complex ground
impedance (based on
entered G value)
8
attenuation due
to screening
(at objects)
for single and double diffraction based on the path difference of the direct
path across the obstacle, screened ray does by default not include a ground
attenuation, screening effect considers wavelength
REMARK: transm. through obstacles not considered by default, in
CadnaA approximative approach using „acoustical Transparency“
effective height he is
reduced by h for single
screen, considers wave
length, screened ray with
ground attenuation
by complex
algorithm
using Fresnel-zone
9
handling of
lateral diffraction
by considering two, lateral ray paths (via the vertical edges of an obstacle),
lateral diffraction includes the ground attenuation by default
for single screen only
yes
10
handling of
multiple obstacles
in ray path
unclear specification („may also be calculated approximately ... by choosing the two most effective barriers ...“)
In CadnaA the so-called „ribbon band method“ is used for the calculation
of the path difference with multiple screening objects.
at multiple screens:
„... find the two most
effective single screens.“
(annex C)
yes
11
attenuation due
to screening
(terrain)
screening by terrain not treated explicitly,
In CadnaA the algorithm for multiple screening objects is applied, however not considering any lateral diffraction.
as with multiple screens
(no lateral diffraction)
yes
12
handling of
meteorological
effects (wind)
2 options (empirical correction Cmet):
1. based on the factor C0
2. additionally in CadnaA: derivation of C0 from a distribution of wind
direction (which is not treated ISO 9613-2 completely)
for „moderate downwind
or slight temperature
inversions“, no meteorol.
correction
for a specific meteo.
situation (using wind
dir. & speed, temp.
gradient)
13
attenuation due to
foliage
based on length of the curved ray path (arc of a circle) passing through the
foliage (with height h) assuming a radius of 5 km
based on transmission
path length (with h)
not available
14
attenuation due to
built-up areas
based on length of the curved ray path (arc of a circle) passing through the
foliage (with height h) assuming a radius of 5 km
acc. to NPM, Annex D
(internal scattering Li)
not available
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Chapter 6 - Calculation
6.2.9 Industry Tab
Standard / Guideline
Ljud fran
vindkraftverk
BS 5228
Harmonoise
(using DLL 2.020)
No
Concawe
NMPB 2008
CNOSSOS-EU
yes
yes
yes
yes
yes
yes
1
yes (for A-weighted
sum level only)
yes (though not part
of original paper)
yes, see ISO 9613
yes, see ISO 9613
yes (1/3 octaves, 100
to 5000 Hz)
yes (for octaves 63 Hz to
8000 Hz, + 31.5 Hz
2
half sphere (2r2)
divergence mixed
with ground attenuation
full sphere (4r2)
full sphere (4r2)
point source propagation (4r2)
point source propagation
(4r2)
3
using 0.005 dB/m
not available
complex transfer
function (via DLL)
based on air absorption coeff. (table)
acc. ISO 9613-1 (for
15°C, 70%)
yes (acc. to ISO 9613-1)
4
see ISO 9613
for two categories
(soft/hard)
see above
specific algorithm,
not by image sources
algorithmic, not by
image sources
algorithmic incl. ground
absorption (see below)
5
not available
see ISO 9613
see above
see ISO 9613
yes
yes
6
two ground categories (over land =
soft,
over water = hard)
ground attenuation
for two categories
(soft/hard) and for
mixed ground
see above
spectral model only
(63 to 4000 Hz, in
CadnaA extended to
32 and 8000 Hz)
spectral model (for
favorable: ISO 96132, for homogeneous
specific)
for 2 prop. conditions
using ground factor G:
- homogeneous cond.
- favorable conditions
7
not available
see ISO 9613
see above
using the Fresnelnumber based on the
path length difference
based on path length
difference
single & double diffraction, includes ground
effect on both sides of
obstacle, with mirror
source and receiver
8
not available
not available
see above
not available
not expressively
considered
by 2 rays at vertical
edges, including ground
effect
9
not available
not available
see above
so-called „ribbon
band method“ is
used to obtain path
length difference
via path length
difference
via path length difference
(convex hull)
10
not available
see ISO 9613
see above
see ISO 9613
as with multiple
screens
see ISO 9613-2
11
not available
not available
for a specific meteorological situation
(using stability class,
wind dir. & speed)
for a specific meteorological situation
(using stability class,
wind dir. & speed)
using occurrences of
homogeneous and
favorable propagation conditions
using occurrences of
homogeneous and favorable prop. conditions,
energetic addition
12
not available
not available
not available
not available
not available
not available
13
not available
not available
not available
not available
not available
not available
14
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90
6
Chapter 6 - Calculation
6.2.9 Industry Tab
Obstacles & Special Objects
6
No
Object Type/
Option
Standard / Guideline
ISO 9613 (1996)
Nordic Pred. M. (1996)
1
building
single & multiple diffraction for edges parallel to the ground (shortest path
difference), lateral diffraction by vertical edges, no reflection or input of
absorption coeff./reflection loss, not normative: input of transmission
coefficient (%), no acoustical transparency by default
diffract. at upper edge,
no lateral diffr. (in NPM
for single edge only), no
acoust. transp.
yes
2
cylinder
single and multiple diffraction via the cylinder based on the shortest path
difference, lateral diffraction via the perimeter, no reflection or by input of
absorption coefficient/reflection loss, reflection up to 1st order (implementation in CadnaA differs from ISO 9613-2 as incomplete there)
diffract. at upper edge,
lateral diffr. as for a
single edge
yes
3
barrier
single and multiple diffraction for edges parallel to the ground based on
the shortest path difference, lateral diffraction via the vertical edges, no
reflection or by input of absorption coefficient/reflection loss
diffract. at upper edge,
lateral diffr. only at the
first vertical edge
yes
4
floating
barrier
no diffraction via the lower edge (screening edge without diffraction),
otherwise see barrier
see ISO 9613
yes
5
barrier with
cantilever
cantilever is totally absorbing (no reflection), calculation of the path length
difference valid for receivers/grid points outside and below the cantilever,
otherwise see barrier
cantilever not available
(not compatible with
„effective height“
concept)
yes
6
bridge plate
diffraction calculation for horizontal plate only (inclined plate approximated to horizontal plate), screening for sources below/above the bridge
plate (diffraction up-/downwards), no reflection-induced level increase
below the bridge plate (as ground is not modeled by mirror sources)
see ISO 9613
no effect
7
embankment
acts as a double barrier, diffraction for direct path (without lateral diffraction), no absorptive/reflective properties
REMARK: The embankment‘s top edge is not considered in the triangulation!
see ISO 9613
yes
8
ground
absorption area
just relevant with the frequency dependent ground attenuation: procedure
uses three regions (source, receiver, and middle region), empirical attenuation based on source and receiver height and distance (accord. to Kragh)
see ISO 9613
no effect
9
built-up area/
foliage
without screening calculation, attenuation based on the length of the
curved ray path (arc of a circle) passing through the built-up area/foliage
assuming a radius of 5 km
no built-up area in NPM
(in CadnaA as in ISO
9613), foliage: based on
path length using heff
no effect
10
3D-reflector
screening using shortest path length difference, two lateral paths, diffraction can be suppressed for up to 32 edges, no reflection or input of
absorption coeff./reflection loss, reflection up to 1st order, no summation
of diffraction components via multiple edges, no multiple diffraction
no screening effect (not
compatible with
„effective height“
concept)
no effect
11
self screening
not relevant
not relevant
not relevant
12
additional width/
parapet L/R
not relevant
not relevant
not relevant
Nord 2000 (V20)
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Chapter 6 - Calculation
6.2.9 Industry Tab
Standard / Guideline
Ljud vindkra.
BS 5228
Harmonoise
Concawe
No
NMPB 2008
CNOSSOS-EU
no effect
diffr. at 1st edge
parallel to the ground
only, no lateral diffr.,
no acoust. transpar.
see ISO 9613, but no
acoustical transparency,
reflection based on airflow resistivity
see ISO 9613
see ISO 9613
see ISO 9613, but
for homogeneous
& favorable conditions
1
no effect
see ISO 9613
see ISO 9613
see ISO 9613
see ISO 9613
for homogeneous
& favorable conditions
2
no effect
diffr. at 1st edge
parallel to the ground
only, no lateral diffr.
see ISO 9613,
reflection based on
airflow resistivity
see ISO 9613
see ISO 9613
see ISO 9613, but
for homog. &
favorable cond.
3
no effect
see ISO 9613
yes
see ISO 9613
see ISO 9613
see ISO 9613
4
no effect
see ISO 9613
yes
see ISO 9613
not available
see ISO 9613
5
no effect
see ISO 9613
no effect
see ISO 9613
see ISO 9613
see ISO 9613
6
no effect
see ISO 9613
yes
see ISO 9613
see ISO 9613
see ISO 9613
7
no effect
see ISO 9613, also
with weighted source
data (based on the
frequency specified)
based on airflow
resistivity
(in CadnaA: classes of
ground factor G)
see ISO 9613, also with
weighted source data
(using specified freq.)
using ground
factor G (for
favorable and
homogeneous)
yes, using ground
factor G (for
favorable and
homogeneous)
8
no effect
no effect
no effect
no effect
not available
no effect
9
no effect
see ISO 9613
no effect
see ISO 9613
not available
see ISO 9613
10
not relevant
not relevant
not relevant
not relevant
see ISO 9613
see ISO 9613
11
not relevant
not relevant
not relevant
not relevant
see ISO 9613
see ISO 9613
12
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6
Chapter 6 - Calculation
6.2.9 Industry Tab
6
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
6.2.9.1
ISO 9613
6
Three options for lateral diffraction are available for selection:
•
none: No lateral diffraction considered, just the direct path sourcereceiver is evaluated.
•
only one object: Lateral diffraction is not calculated if more than one
object intersects the line connecting the source to the receiver point.
•
some objects: The two shortest possible convex rays around the
arrangement of objects are determined and used for the calculation of the
lateral diffraction.
This setting defines the distance between source and receiver for which
lateral diffraction is taken into account. The default value is 1000 m.

The limit of the screening attenuation Dz for single and multiple
diffraction accord. to ISO 9613-2, section 7.4, is in CadnaA not applied
to the two lateral paths, but to the direct path only. Otherwise, the
screening attenuation for single or multiple diffraction resp. would get
limited to 20-10 lg (3)=15.2 dB or 25-10 lg (3)=20.2 dB, respectively
(see also section "Barrier Attenuation" below).
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Lateral Diffraction
if Distance smaller (m)
94
6
Lateral Diffraction with
multiple Edges or Objects
Chapter 6 - Calculation
6.2.9.1 ISO 9613
With CadnaA release 4.3 the strategy when calculating lateral diffraction
around objects with more than one diffracting edge or multiple objects has
been changed. Now, the parameter e (distance between first and last
diffracting edge) is considered when calculating C3 according equation 15 of
ISO 9613-2 /8/. In previous releases, the constant value C3=1 was used
instead.

6
The change refers to the calculation of the lateral diffraction only. For
the direct path, however, the parameter e has always been and is still
taken into account when calculating C3.
By a local text block OPT_OLD_CALC and the text SBEUG_e0_X141=1,
the former value C3=1 can be set. If this text block does not exist or the value is zero (SBEUG_e0_X141=0), the new strategy is used.

Level Increase due to
Lateral Diffraction
By selecting the option „none“ (i.e. no lateral diffraction, see above) it
can be easily checked that the screening effect for the direct path does
not change, regardless of whether the text block is set or not.
With calculations accord. to ISO 9613-2 the receiver level including an obstacle (e.g a building) and terrain can be higher, than just with terrain (e.g. with
the buildings deactivated). When calculating the screening effect by terrain no
lateral diffraction is calculated. With an additional obstacle, however, the effect by lateral diffraction by that obstacle is added. This could cause an increase of the local receiver level.
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
Therefore, in case the screening effect by an obstacle is smaller than without
(i.e. with terrain only) the screening effect ignoring the obstacle is considered
by CadnaA. This strategy can be deactivated using the local text block
OPT_OLD_CALC with the text VERSION_X=115.
6
Example
 Examples\06_Configuration\ISO 9613
actual default setting for
lateral diffraction accord. to
ISO:
Level with obstacle (e.g. with
building) must be lower than
without.
(no local text block
OPT_OLD_CALC with text
VERSION_X=115)
file ISO - lateral diffraction &
terrain - 1.cna
former effect due to lateral
diffraction:
higher receiver level with
building, than without
(with local text block
OPT_OLD_CALC with text
VERSION_X=115)
file ISO - lateral diffraction &
terrain - 2.cna
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6
Chapter 6 - Calculation
6.2.9.1 ISO 9613
Screening & Ground
Attenuation
The following options are available to account for the ground attenuation in
conjunction with the calculation of the screening effect.
Exclude Ground
Attenuation over Barrier
With this setting the ground attenuation is excluded from the total
attenuation of screened rays. This is the default setting in CadnaA.
Explanatory Remarks:
ISO 9613-2, equation (12) states (for top edge): Abar  Dz  Agr  0 dB
In conjunction with equation (4): A  Adiv  Aatm  Agr  Abar  Amisc
6
it results that for screened rays no ground attenuation Agr is considered:
A  Adiv  Aatm  Agr  Dz  Agr   Amisc  Adiv  Aatm  Dz  Amisc
This setting is, therefore, in line with the specifications in ISO 9613-2.
Include Ground
Attenuation over Barrier
The ground attenuation is included in the total attenuation of screened rays.
The mean height above ground of the ray between source and receiver when
passing over the barrier is considered in the calculation.
Explanatory Remarks:
With this option the equation (13) of ISO 9613-2 is applied: Abar  Dz  0 dB
This equation holds as well for the two lateral paths. For the total attenuation it results
according to equation (4):
A  Adiv  Aatm  Agr  Dz  Amisc
In this case, the ground attenuation Agr is considered also for the diffracted rays.
10 m-Criterion
When a source is higher than 10 m above ground and at least one screening
edge is higher than 10 m above ground, accord. to ISO 9613-2, note 15,
equation (13) is used to calculate the attenuation by a barrier Abar (with Abar
= Dz > 0 dB).
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
For the barrier attenuation the following options are available from the list
box:
•
•
•
•

Barrier Attenuation
Dz without limit
Dz with limit (20/25)
De,o with limit
Dz with limit (20/20)
The limitation refers in any case to the direct path only. The barrier
attenuation resulting for the two lateral paths is not limited in CadnaA
(see also section "Lateral Diffraction" above).
6
With this option activated the barrier attenuation Dz increases with increasing
path difference z without any limitation (accord. to equation (14) in ISO
9613-2).
Dz without limit
According to ISO 9613-2 the barrier attenuation Dz is limited to 20 dB for a
single, and to 25 dB for a two or more screening edges. Therefore, this is the
default setting.
Dz with limit 20/25
The option „De,o with limit“ refers to the former German guidelines VDI
2714 /38/ and VDI 2720-1 /40/. This setting is not relevant for ISOcalculations, but has to be kept to ensure downward compatibility with old
projects.
De,o with limit
According the new Austrian edition of ISO 9613-2 (see ÖNORM ISO 96132:2008-01) the barrier attenuation Dz of two or more screening edges is for
Austria limited to 20 dB, thus deviating from the original document.
Dz with limit 20/20
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6
No Subtraction of
negative Ground
Attenuation
Chapter 6 - Calculation
6.2.9.1 ISO 9613
With this option activated, a negative ground attenuation (e.g. with reflecting
ground) will be ignored when calculating Abar. Consequently, the total
attenuation A considers the ground attenuation Agr for the screened ray. So,
with reflecting ground, equation (12) of ISO 9613-2 is not applied, but
equation (13).
By default, this option is deactivated as ISO 9613-2 does not specify this
additional condition (Agr > 0 dB).
Explanatory Remarks:
6
Equation (12) in ISO 9613-2 is: Abar  Dz  Agr  0 dB
For low frequencies and absorbing ground or generally with reflecting ground the
ground attenuation Agr becomes negative. In this case, the attenuation due to a barrier
Abar would be increased since the ground attenuation Agr would be added to the barrier
attenuation Dz. With this option activated, it will be used for the screened ray instead:
Abar  Dz  0 dB
Thus, when calculation the total attenuation A the ground attenuation Agr is considered
according to:
A  Adiv  Aatm  Agr  Dz  Amisc
No negative path
difference
With activated option no barrier attenuation is calculated when the ray from
the source to the receiver is above the upper edge of the barrier. By default,
this option is deactivated
Explanatory Remarks:
The barrier attenuation Dz according to equation (14) in ISO 9613-2 produces a distinct
screening effect even when the ray passes slightly above the barrier’s top edge. ISO
9613-2, section 7.4, states that the path difference z receives a negative sign in this case.
By this approach, the calculation model according to ISO 9613-2 accounts for the theoretical fact from diffraction theory that the screening effect does not vanish instantly in
case the ray passes just a little above the screening edge. If this option is activated, Abar
is set to zero at a negative z.
CadnaA - Reference Manual
Chapter 6 - Calculation
6.2.9.1 ISO 9613
In ISO 9613-2, two methods are mentioned to calculate the ground
attenuation Agr:
1.
„general method“: method in frequency bands according to section
7.3.1 with the ground factor G as parameter,
2.
„alternative method“: method for A-weighted levels according to section 7.3.2 not applying the ground factor G.
As in projects the sound emission of sources can either be given in spectral
form or as A-weighted levels, several possibilities exist to calculate the
ground attenuation. In CadnaA four calculation options are available:
Designation
Procedure
none
no ground attenuation at all
However, the ground reflection is still accounted for by
using equation (11) of ISO 9613-2.
not spectral
method 7.3.2 is used in all cases
For spectral sources the same value of Agr results for all
octaves.
spectral, spectral sources only
The method 7.3.1 is used for all spectral sources, in all
other cases the method 7.3.2 is used.
This corresponds in CadnaA, version 3.3 and former,
with the option „Ground Attenuation spectral“ being
activated.
spectral, all sources
Method 7.3.1 is used in all cases, for non-spectral sources
the corresponding octave band is used.
For A-level sources the value for Agr at the specified frequency is used.
WEA interim (-3 dB)
A fixed value for Agr of -3 dB is used with A-weighted or
for all octaves with spectral calculations (according to the
German LAI interim method for wind turbine noise
assessments /123/).
The directivity index D_omega is 0 dB in both cases.
The default setting in CadnaA is the option „spectral, all sources“ as this is
the „general method of calculation“ according to ISO 9613-2.
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Ground Attenuation
6
100
6
Non-spectral Ground
Attenuation
Chapter 6 - Calculation
6.2.9.1 ISO 9613
With non-spectral ground attenuation selected ("alternative method"), the
mean height h_m is calculated in CadnaA, starting from release 4.1, based
on the 3D distance (distance d in Figure 3, ISO 9613-2 /8/). This change,
now corresponding strictly with the standard’s specification (d in equation
(10) denotes the 3D distance, see Figure 3), causes at receiver points above
and below the source the ratio h_m/d to become very small, resulting in
Agr = 4.8 dB.
Prior to CadnaA release 4.1 of the horizontal distance (2D distance) was
used instead to prevent this effect. This implementation, however, was not
strictly in line with the standard’s specification (see illustrations).
6
 Examples\06_Configuration\ISO 9613
vertical level distribution,
Agr from 3D distance,
w/o textblock or with
textblock OPT_OLD_CALC with the text
ISO_HM_X137=0
(file ISO - alt. proc. - Agr
from 3D distance.cna)
vertical level distribution,
Agr from 2D distance,
with textblock
OPT_OLD_CALC with
the text ISO_HM_X137=1
(file ISO - alt. proc. - Agr
from 2D distance.cna)
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
6 101
The previously used procedure can be toggled using the local text block
OPT_OLD_CALC with the text ISO_HM_X137 = 1.
The procedure applied in CadnaA to evaluate the mean height h_m in the
non-spectral ground attenuation model („alternative method“ in chapter
7.3.2 of ISO 9613-2 /8/) is as follows:
•
The line of sight source-receiver (ray path) is not blocked by obstacles or
terrain: CadnaA evaluates the area below the ray path and the 3D-distance source-receiver (as shown in Figure 3, ISO 9613-2). The internal
calculation procedure evaluates distances and heights step-by-step for
each point of terrain or obstacle/s in the ray path.
•
The line of sight is blocked by obstacles or terrain: This case is not treated
in ISO 9613-2 explicitly. As CadnaA applies the "rubber-band-method"
to calculate the screening effect by multiple objects, a similar rule is
applied here: The area below the diffracted path source-receiver minus the
area of obstacles or terrain in path is used to calculate the area F, giving in
conjunction with the 3D distance the mean height h_m.
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Mean Height with nonspectral Ground
Attenuation
6
102
6
Chapter 6 - Calculation
6.2.9.1 ISO 9613
The latter case is illustrated in more detail by a simple example: Assume a hill
in line of sight being a symmetrical triangle in cross-section. The area relevant
for h_m is the area below the red line (diffracted ray path) minus the green
hatched area (hill area).
6
spectral Ground
Attenuation
When calculating the ground absorption in frequency bands („general method“ according to ISO 9613-2) the global ground absorption for areas not
covered by the object "Ground Absorption" (see chapter 3.4) is defined via
the „Ground Absorption“ tab (see chapter 6.2.7). A default value of G=1 is
used (porous ground).
In contrast to the „alternative method“ the 2D distance is used by the
„general method“ to calculate the ground attenuation (dp).
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Obstacles within Area
Source do not Shield
Example
6
Area source with 2 buildings inside, option activated: sources with
free propagation (with all rays displayed)
With this option activated the result levels are calculated as if the obstacles
were not present (i.e. no screening effect).
Area source with 2 buildings inside,
option deactivated: sub-sources behind the buildings are screened,
sub-sources in front of buildings with free propagation (screened rays in RED)
With this option deactivated lower levels result at the receiver points due to
the screening effect of the obstacles inside. Nevertheless, for all other sources
(i.e. sources outside of the are source’s border) the obstacles inside cause always screening.

The decision whether an obstacle is located inside of an area source is
based on the location of the obstacle’s first polygon point.
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6
Sources in Building/
Cylinder do not shield
Chapter 6 - Calculation
6.2.9.1 ISO 9613
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.

In this case, prior to the calculation, a message will be displayed (dialog
Consistency Check) which enables to proceed with the operation
(button „Continue“).
This procedure is due to the fact that buildings and cylinders are treated as
open boxes within the calculation of propagation (despite they are displayed
as „closed“ objects (i.e. with roof) on the 3D-Special View).
6
With this option activated, sources located inside of the geometrical borders
of buildings or cylinders are not screened as if the obstacle were not present.
For sources outside, those obstacles are always screening and - if any reflecting. This option enables to model e.g. sound radiating chimneys by using point or line sources located inside the cylinder. In this case, the
directivity pattern of the chimney - whether entered or selected from the
default directivities - will not distorted by the cylinder’s screening edge.
Example
see manual „Introduction to CadnaA“, chapter 6.3 Directivity
Barrier Coefficient
The barrier coefficients C1, C2 and C3 according to ISO 9613-2 can be
edited. This option enables to adapt the barrier equation to special
applications (see /8/, section 7.4).

In ISO 9613-2 the coefficient C1 is not expressed explicitly. The first
constant („3“) in equation (14) corresponds with C1.
The default values are: C1 = 3 dB; C2 = 20 dB; C3 = 0 dB.
The input C3 = 0 dB causes this value to be calculated according to ISO
9613-2, equations (15), (16) and (17) for single and double barriers
automatically.
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
The air attenuation is calculated based on the temperature and the relative
humidity according to ISO 9613-1. Intermediate frequency values result from
linear interpolation. The temperature specified serves also as the ambient
temperature when calculating the exhaust stack’s directivity.

Temperature / rel.
Humidity
Regarding the calculation of the air attenuation for octave 31.5 Hz see
section "Additional Information" at the end of this chapter.
Explanatory Remarks:
CADNAA calculates the air attenuation according to equations (3), (4) and (5) of section
6.2 ISO 9613-1/8/. This also holds for intermediate input values and for input values
outside the range of list boxes.
By default, the above-mentioned equations just apply to the air attenuation of pure
tones. Section 7 of ISO 9613-1 provides information on the accuracy of the attenuation
coefficients for certain ranges of input values (for final accuracies of +/- 10%, +/- 20%,
+/- 50%). Section 8 of ISO 9613-1 provides information on the accuracy of the air
attenuation when transferring the pure-tone method to band-level attenuation (for
third-octaves or octaves). Refer to this information - if required - when using input data
outside the range of tabulated attenuation coefficients of ISO 9613-1:
- frequency from 50 Hz to 10 kHz,
- temperature from -20 ° C to +50 ° C,
- relative humidity from 10% to 100%, and
- air pressure of 101,325 kPa (one atmosphere).
For calculations according to ISO 9613-2 a user-defined air attenuation spectrum can be referenced. Enter a spectrum in the local library "Absorptions"
with the ID "SYS_ATM_ABSORB". The values have to be specified in dB/
km. Missing octave band data will be considered as 0 dB/km.
Local Absorption Spectrum SYS_ATM_ABSORB
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User-defined Air
Attenuation
106
6
Chapter 6 - Calculation
6.2.9.1 ISO 9613
Meteorology
For calculations according to ISO 9613 the following options are available:
none
No correction is applied. The resulting equivalent continuous sound pressure
level is calculated applying equation (3) for the meteorological situation as described in ISO 9613-2, section 5 (downwind).
Cmet, C0 constant
This option calculates the long-term average A-weighted sound pressure level
according to ISO 9613-2, equation (6). This requires to specify the value of
C0 for the periods Day/Evening/Night where the meteorological correction
Cmet is calculated from according to ISO 9613-2, section 8, equations (21)
and (22) resp.
6
The factor C0 may be estimated from an elementary analysis of the local meteorological statistics or may be established by the local authorities.
Cmet, C0 from
wind statistics
With this option two methods for calculation of C0 from wind statistics are
available on the subsequent dialog Wind Statistics:
 method LfU Bayern: The approach used by the LfU-Bayern (Bavarian
Environmental Agency) to calculate C0 is:
Kq
Kg
K
T
 m


Tq
Tg
C 0  10 lg m 10 10 
10 10 
10 10
 100
100
100

where
Tm
Km
Tq
Kq
Tg
Kg




percentage of annual downwind situations and calmness (inversions) in %
level difference to the downwind situation in dB
percentage of annual cross-wind situations in %
level difference of cross-wind situations to the downwind situation in dB
percentage of annual upwind situations in %
level difference of upwind situations to the downwind situation in dB
The percentages T for downwind, crosswind, and upwind result from
the wind frequencies in the following sectors:
- down: +/-45° in direction of propagation (=90° sector) and calmness,
- cross: 45° to 135° and 225° to 315° in direction of propagation,
- up: +-45° opposite to the direction of propagation (=90° sector).
Example for method „LfU
Bayern“
see chapter 6.6.2 "Correction based on Wind Statistics" in the manual
„Introduction to CadnaA“.
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
 method LUA NRW: The approach used by the LUA NRW (Environmental Agency of North-Rhine-Westphalia) to calculate C0 is:
Lz    5  5 * cos  45 sin  
where 
wind direction referring to downwind
And
c  h  * 10 lg100.1*L  
6
with the frequency h() in wind sector 1 to 2:
h   h1  h 2  h1*
where 
  1
 2  1
angle 0-360 degrees
The value C0 results by summation from:
 c
C0  10 lg  
in dB
 100 
This means that at large distances and on a long-term annual average
basis the attenuation with cross winds is 1.5 dB and with upwind 10
dB. The frequency of calmness is evenly distributed among the 12
wind sectors. The values of C0 for the locations investigated by LUA
NRW range from 1 dB to 3.9 dB.
relevant for Germany only!
According to the „Vorläufige Berechnungsmethode für den Umgebungslärm
durch Industrie und Gewerbe (VBUI)“ /116/ the following values for C0 are
to used when calculating Cmet:
C0,Day = 2 dB; C0,Evening = 1 dB; C0,Night = 0 dB
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VBUI
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6
Concawe
Chapter 6 - Calculation
6.2.9.1 ISO 9613
With former releases of CadnaA an additional option enabling to apply the
meteorological correction K4 according to CONCAWE /1/ was offered. As
the entire CONCAWE model is now available in CadnaA this option has
been removed. However, it can be reactivated by adding the following lines to
the MAIN-section of the file CADNAA.INI:
[Main]
IsoCmetConcawe=1

6
In order to locate the INI-file use the command Open INI-file on the
Options menu (see Chapter 2 - Installation, section "INI-files", in the
manual „Introduction to CadnaA“).
When this option is selected from the „Industry“ tab the correction term
Cmet in the ISO 9613-2 calculation is replaced by K4 from CONCAWE.

Please consider that the ISO model by default addresses a moderate
downwind situation. In ISO 9613-2, the term Cmet corrects for a longterm average level with a different meteorological situation than the
default situation. As the meteorological correction K4 according to
CONCAWE itself represents a distinct meteorological situation, it is
questionable what the term K4 in conjunction with the downwind
approach is focusing at. This option was formerly introduced into
CadnaA based in user requests.
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Chapter 6 - Calculation
6.2.9.1 ISO 9613
Additional
Information
By default, calculations according to ISO-9613-2 just cover the frequency
range for octaves from 63 to 8000 Hz. Based on user requests, CadnaA
offers the octave band at 31.5 Hz in addition.
Calculations for octave
31.5 Hz
For predictions in the 31.5 Hz octave band the following rules apply:
•
atmospheric absorption Aatm: The standard ISO 9613-1 /8/ provides
equations which are used to calculate the air absorption in the 31.5 Hz
octave band.
•
frequency dependent ground attenuation Aground: The same equations as
for the octave band at 63 Hz are used.
•
barrier attenuation (Dz): The equation (14) as for all other octave bands is
used, however, with the wavelength at 31.5 Hz.
•
reflection criterion: The equation (19) as for all other octave bands is
used, however, with the wavelength at 31.5 Hz.
•
objects „Foliage“ and „Housing Attenuation“: The same equations as for
the octave band at 63 Hz are used.
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110
6
Chapter 6 - Calculation
6.2.9.1 ISO 9613
6
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Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
6.2.9.2
Nordic Prediction Method (1996)
6
Three options for lateral diffraction are available for selection:
•
none: no lateral diffraction considered, just the direct path is evaluated.
•
only one object: This option has in conjunction with NPM the same
effect as „none“ and should, therefore, NOT be used.
•
some objects: In conjunction with NPM this option causes the two shortest possible convex rays around the first diffracting edge to be determined
and used in the calculation.

Due to restrictions in Nordic Prediction Method, lateral diffraction
occurs just at the first diffracting edge. Consequently, a further barrier
behind a first barrier in ray direction will not cause a lateral diffraction.
Also at buildings (being multi-point objects) no lateral diffraction
occurs.
This setting defines the distance between source and receiver for which
lateral diffraction is taken into account. The default value is 1000 m.
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Lateral Diffraction
if Distance smaller (m)
112
6
Obstacles within
Area Source do not
Shield
Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Example
6
Area source with 2 buildings inside, option activated: sources with
free propagation (with all rays displayed)
With this option activated the result levels are calculated as if the obstacles
were not present (i.e. no screening effect).
Area source with 2 buildings inside,
option deactivated: sub-sources behind the buildings are screened,
sub-sources in front of buildings with free propagation (screened rays in RED)
With this option deactivated lower levels result at the receiver points due to
the screening effect of the obstacles inside. Nevertheless, for all other sources
(i.e. sources outside of the are source’s border) the obstacles inside cause always screening.
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Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
The air attenuation is calculated based on the temperature and relative
humidity as given in annex B of the paper /71/. Intermediate frequency
values result from linear interpolation. The temperature specified serves also
as the ambient temperature when calculating the exhaust stack’s directivity.
Temperature / rel.
Humidity
The entered wind speed will be used in the calculation of the directivity of
chimneys (see chapter 2.2.1 "Sound Radiation from Chimneys or Stacks").
Wind Speed for
Directivity (m/s)
6
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6
Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
Additional
Information
Diffraction Model
The screening model for industrial noise of Nordic Prediction Method /71/
covers the diffraction effect with just a single screening edge. With two or
more edges, there is no specification on how to apply the concept using the
additional height h to multiple screening edges.
In section 4.5.1 of /71/ it says:
„The general principle in calculating the screening correction, Ls, is to identify all screening obstacles between source and immission point. ... The calculation procedure depends on the number of screens present. Usually only one
screen is taken into account. Ls is then calculated according to section 4.5.4.
If more than one screen are present, the procedure in Appendix C [„Screening by more than one screen“, see section „Multiple Screens“ below] should
be applied.“
6
Section 4.5.4 describes the procedure for a single screening edge. The
additional height h above the direct path is calculated from the horizontal
distance (2D-distance) from source and receiver, respectively. The remaining
height to the barrier’s top edge is the so-called „effective“ height he which is
used to evaluate the path difference.
Lateral Diffraction
For the lateral path it is stated on page 37: „When a building is represented by
a single screen, r and l [path differences] are calculated for the edges yielding
the highest values.“
This expresses that the diffraction model cannot handle several edges neither
for the direct (vertical), nor for the lateral paths (horizontal). In figure 4.5.7
(sectional view) just the first edge of the building is addressed (as if it would
be a flat barrier).
Multiple Screens
Annex C describes for an arrangement of multiple screens with respect to the
direct path on how to evaluate „the two most effective single screens“ („effective“ with respect to the ray’s elevation angle is meant). However, nothing
is said on how to account for lateral diffraction in this case.
In note 1 it says: „It must be emphasized that the recommended procedure is
of rather speculative nature ...“
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Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
As annex C does not address the application of this scheme to the lateral
paths in an arrangement with multiple screening objects, CadnaA applies the
lateral path calculation to the first screening edge only.

Applying the „ribbon band method“ for multiple objects (as with ISO
9613-2) would cause a level difference compared to the procedure used
for a single screening edge only.
Comparing lateral diffraction using ISO 9613-2 and NPM.
Object
ISO 9613-2
Nordic Prediction Model (1996)
lateral diffraction occurring at 1st and
2nd vertical edge
no lateral diffraction due to the
restrictions of the diffraction model
lateral diffraction occurring at 1st and
2nd barrier
lateral diffraction occurring at 1st
barrier, but not at 2nd barrier
building (height
100 m), option
„some objects“
for lateral
diffraction
selected
two barriers
behind each
other (height
100 m each),
option „some
objects“ for
lateral
diffraction
selected
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Example
6
116
6
Attenuation due to
Vegetation
Chapter 6 - Calculation
6.2.9.2 Nordic Prediction Method (1996)
The Nordic Prediction Method distinguishes between a single and multiple
vegetation areas in the ray path. For a single vegetation area, the attenuation
depends on the length of the ray passing through the foliage (considering the
additional height h above the direct path). For multiple vegetation areas, the
attenuation depends on the number of vegetation areas, with a maximum of
four.
In CadnaA, the attenuation Lv for a single and multiple vegetation areas is
always calculated based transmission path length dv (considering the
additional height h) and not on the number of groups of vegetation:
6
Lv  nV   v with nV 
dv
4
50
where
dv: transmission path length (m)
v: attenuation coefficient accord. to table 4.6.1 of /71/
Attenuation due to
Internal Scattering
The object „Built-Up Area“ in CadnaA applies the algorithm for so-called
„internal scattering Li“ given in Nordic Prediction Method, annex D. The
attenuation Li“ calculates from:
 Li   i   d i  10 dB
with
di: transmission path length (m)
iattenuation coefficient accord. to table D of /71/
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Chapter 6 - Calculation
6.2.9.3 Nord 2000
6.2.9.3
6 117
Nord 2000
6
The implementation of "Nord 2000 Industry" in CadnaA makes use of the
dynamic link library Nord2000.dll distributed by the Norwegian Public
Roads Administration (http://www.vegvesen.no) and developed by the
Scandinavian research organization SINTEF (http://www.sintef.no). This
DLL is part of the CadnaA installation procedure.

Since DataKustik is not the developer, we can neither comment, nor
explain results obtained using this DLL. In case of inquiries please
contact NPRA or SINTEF.

Since there is no 64-bit DLL available, Nord 2000 cannot be used with
CadnaA 64-bit version. Furthermore, the 32-bit DLL developed by
SINTEF has no multi-threading capabilities. Consequently, just a single
core will be used slowing down the calculation with complex sceneries.
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General Information
118
6
Nord 2000 DLLVersion
Chapter 6 - Calculation
6.2.9.3 Nord 2000
On the list box „Version“ the available versions of the Nord2000.dll are
listed. The most recent is selected by default.
After the first calculation using Nord 2000 (Industry) the DLL-version will
be displayed.
Obstacles within Area
Source do not shield
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
for an example see chapter 6.2.9.5 "BS 5228"
6
Sources in Building/
Cylinder do not shield
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.

In this case, prior to the calculation, a message will be displayed (dialog
Consistency Check) which enables to proceed with the operation
(button „Continue“).
This procedure is due to the fact that buildings and cylinders are treated as
open boxes within the calculation of propagation (despite they are displayed
as „closed“ objects, i.e. with roof, on the 3D-Special View).
With this option activated, sources located inside of the geometrical borders
of buildings or cylinders are not screened as if the obstacle were not present.
For sources outside, those obstacles are always screening and - if any - reflecting. This option enables to model e.g. sound radiating chimneys by using
point or line sources located inside the cylinder. In this case, the directivity
pattern of the chimney - whether entered or selected from the default
directivities - will not distorted by the cylinder’s screening edge.
Example
see manual „Introduction to CadnaA“, chapter 6.3 Directivity
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Chapter 6 - Calculation
6.2.9.3 Nord 2000
The Nord 2000 model applies a specific input data set for the meteorological
correction using the following input data:
Meteorology
The air attenuation is calculated based on the temperature and relative
humidity. Intermediate frequency values result from linear interpolation. The
temperature specified serves also as the ambient temperature when calculating the exhaust stack’s directivity.
Temperature / rel. Humidity
The height at which the wind speed was measured (default value: 10 m).
Height of Wind (m)
The roughness length characterizes the turbulence conditions of the
atmospheric boundary layer. This parameter is used in the vertical wind profile equations predicting the horizontal mean wind speed near the ground
(default value: 0.025 m).
Roughness length (m)
6
For information, some typical roughness lengths are listed in the table below
referring to the CORINE cadastre:
z0 in m
Classes according to the CORINE cadastre
0.01
Beaches, dunes, sands (331); Water bodies (512)
0.02
Dump sites (132); Pastures (231); Natural grasslands (321); Sparsely vegetated
areas (333); Salt marshes (421); Intertidal flats (423); Water courses (511); Estuaries (522)
0.05
Mineral extraction sites (131); Sport and leisure facilities (142); Non-irrigated
arable land (211); Glaciers and perpetual snow (335); Coastal lagoons (521)
0.10
Airports (124); Inland marshes (411); Peat bogs (412); Sea and ocean (523)
0.20
Road and rail networks and associated land (122); Green urban areas (141);
Vineyards (221); Complex cultivation patterns (242); Land principally occupied
by agriculture, with significant areas of natural vegetation (243); Moors and
heathland (322); Bare rocks (332)
0.50
Port areas (123); Fruit trees and berry plantations (222); Transitional woodlandshrub (324)
1.00
Discontinuous urban fabric (112); Industrial or commercial units (121);
Construction sites (133); Coniferous forest (312)
1.50
Broad-leaved forest (311); Mixed forest (313)
2.00
Continuous urban fabric (111)
This option is not available for the time being.
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Stability Class D/E/N
120
6
Chapter 6 - Calculation
6.2.9.3 Nord 2000
Wind Direction (°) D/E/N
The wind direction is the direction from which a wind originates (with 0° being North wind, i.e. wind blowing from North, with 180° being South wind
etc.).
Wind Speed (m/s) D/E/N
The wind speed refers to the specified height at which the wind speed was
measured (see above).
Standard Deviation Wind
Speed (m/s) D/E/N
This is the standard deviation of the wind speed in the direction of
propagation.
In the documentation of Nord 2000 it says /75/:
6
„The standard deviation ... accounts for the fluctuation in wind speed in excess of what is already included in the turbulence strength. Turbulent motion
is fluctuations taking place within seconds or minutes. For calculation of instantaneous sound pressure levels (the standard deviation) shall be zero. For
calculation of the equivalent sound pressure level with duration above a few
minutes up to a few hours, the effect of slow variations in wind speed can be
taken into account by this parameter. The parameter should not be used for
calculating long-term effects where the weather is basically changing during
the time. Instead a procedure where the weather is divided into a number of
meteorological classes should be used.“
Temperature Gradient
(°/km) D/E/N
The atmospheric temperature gradient in degrees centigrade per kilometer
height.

This gradient is negative under normal situations (temperature decrease
with height, e.g. about -6°C/km or -0.006°C/m). In inversions,
however, the gradient becomes positive, i.e. a temperature increase with
height.
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Chapter 6 - Calculation
6.2.9.3 Nord 2000
In the documentation of Nord 2000 it says /75/:
„The turbulence strength corresponding to the wind Cv2 accounts for the turbulent motion of the atmosphere. The parameter is not available in standard
weather data. The maximum observed value of Cv2 is approx. 0.3 m4/3s-2, and
it is recommended to use a value of 0.12 m4/3s-2 unless other information is
available.“
In the documentation of Nord 2000 it says /75/:
„The turbulence strength corresponding to the temperature CT2 accounts for
the turbulent variation of the temperature in the atmosphere. The parameter
is not available in standard weather data. The maximum observed value of
CT2 is approx. 0.05 Ks-2, and it is recommended to use a value of 0.008 Ks-2
unless other information is available.“
In the documentation of Nord 2000 it says /75/:
„The standard deviation of fluctuations in the temperature gradient dt/dz accounts for fluctuation in temperature gradient in excess of what is already included in the turbulence strength. It is recommended to use a value of zero
unless other information is available.
Together with the air temperature the relative humidity is used to predict the
attenuation due to air absorption. The value is normally available in standard
weather data.“
CadnaA - Reference Manual
Turbulence Parameter for
Wind Cv2 (m4/3s-2) D/E/N
Turbulence Parameter for
Temperature CT2 (K/s2)
D/E/N
Standard Deviation of
Fluctuations of the
Temperature Gradient
dt/dz (°C/m) D/E/N
6
122
6
Chapter 6 - Calculation
6.2.9.3 Nord 2000
Additional Information
Ground Absorption
In CadnaA, the ground factor G and the absorption coefficient Alpha are
transformed by linear interpolation to an air resistivity according to:
•
for the ground factor G (as entered on the Configuration dialog,
„Ground Absorption“ tab, see chapter 6.2.7, and for the object „Ground
Absorption“, see chapter 3.6):
ground factor G
airflow resistivity 
(kNsm-4)
6
•
0
20000
0.33
1000
0.50
600
0.67
400
1.00
50
and for the absorption coefficient Alpha of buildings and barriers (see
Chapter 3 - Obstacles):
absorption coefficient
Alpha
airflow resistivity 
(kNsm-4)
0
20000
0.25
1000
0.50
600
0.75
400
1.00
50
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Chapter 6 - Calculation
6.2.9.4 Ljud från vindkraftverk
6.2.9.4
6 123
Ljud från vindkraftverk
6
The same configuration settings as for Nordic Prediction Method for
industrial noise apply.
Please refer to chapter 6.2.9.2 "Nordic Prediction Method (1996)".
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6
Chapter 6 - Calculation
6.2.9.4 Ljud från vindkraftverk
Additional Information
Propagation Model
The guideline states different equations for the geometrical divergence over
land and over water, for land depending on the distance r to the receiver.
•
propagation over land:
 for distances r <= 1000 m:
L p , A  LWA , korr  8  20 lg r  0.005 r
6
where
LWA,korr
A-weighted sound power level, corrected for terrain roughness and
r
statistical error (see below)
distance source-receiver (m)
 for distances r > 1000 m:
L p , A  LWA , korr  10  20 lg r  La
where
LWA,korr
A-weighted sound power level, corrected for terrain roughness and
r
La
statistical error (see below)
distance source-receiver (m)
correction calculated according to:
La  10 lg 10 Li  Ai  / 10  10 lg 10 Li  Ai  r  ai  / 10
•
where
Li
A-weighted sound pressure level (background level) at the receiver
Ai
A-weighting for octave data, 63 to 4000 Hz (dB)
ai
air absorption (dB/m)
propagation over water:
 r 
L p , A  LWA, korr  8  20 lg r  La  10 lg

 200 

The correction term La is not evaluated by CadnaA and, thus, has to
be accounted for after calculation.
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Chapter 6 - Calculation
6.2.9.4 Ljud från vindkraftverk
The correction for terrain roughness vh (based on the roughness length z0)
is not considered by CadnaA as this is part of the emission data. This correction will have to be calculated externally and to be added to the sound power
level PWL.
Terrain Roughness
The statistical error k is also considered to be part of the emission (see also
example on page 25 of /74/). Again, this correction will have to be calculated
externally and to be added to the sound power level PWL.
Statistical Error
The object „Ground Absorption Area“ (see chapter 3.4) can be applied in
conjunction with the tab „Ground Absorption“ (see chapter 6.2.7) with
"Ljud från vindkraftverk". There are two cases to be distinguished by the
ground factor G:
Ground Absorption
•
propagation over land (soft ground): G > 0.5
•
propagation over water (hard ground): G <= 0.5
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Chapter 6 - Calculation
6.2.9.4 Ljud från vindkraftverk
6
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Chapter 6 - Calculation
6.2.9.5 BS 5228
6.2.9.5
6 127
BS 5228
6

The following specifications refer to edition 2009 of the standard /84/.

BS 5228 does neither account for lateral diffraction, nor for meteorological effects.
By activating this option the spectral screening model of BS 5228 is applied
to non-spectral sources as well (see figure F.3 in BS 5228). In this case, the
attenuation due to screening at the specified frequency is used.
When this option is not activated the attenuation at non-spectral sources
depends just on the visibility of the top of the source from the receiver (see
section F.2.2.2.1 in BS 5228). In CadnaA, this attenuation depends on the
path difference z:
•
•
•

z < -0.25 m: Ascreen = 0 dB („visible“)
-0.25 <= z <= 0.25 m: Ascreen = 5 dB („just visible“)
z > 0.25 m: Ascreen = 10 dB („not visible“)
The limits for the path differences are not stated in BS 5228, but result
from a common agreement of UK resident users on how the term „just
visible“ translates into a path difference.
CadnaA - Reference Manual
Use diagram F.3 for
screening of
non-spectral sources
128
6
Line sources are
haul roads (F.2.5)
Chapter 6 - Calculation
6.2.9.5 BS 5228
By activating this option, the propagation by line sources will no longer be
influenced by soft ground. In other words, the ground attenuation being used
for line sources refers always to reflective ground, independently of what
ground factor G is specified.
Furthermore, the CadnaA-protocol (see chapter 6.5) specifies in this case on
column Kh’ no longer the divergence-ground attenuation term as specified
by BS 5228 (see below), but the sum of the divergence and the angle
correction according to:
6
K 'h  Adiv  Aangle  10 lg
rsegment
1m
 10 lg

180
where
r
is the distance from the center of the source segment to the receiver (m),
 is the angle of view of that source segment seen from the receiver, (degrees).

In this respect, the procedure applied is similar to the one used in
CadnaA for calculations according to CTRN/CRN.
Explanatory Remarks:
For mobile items of a plant, a separate model is used (section F.2.5 of the standard)
which is not consistent with the general calculation method (section 2.3 of the standard).
While the general calculation method accounts for the ground attenuation (over hard,
soft, and mixed ground, see below) the receiver level LA,eq for well-defined routes, e.g.
haul roads, results from the following equation:
LA, eq  LWA  33  10 lg Q  10 lg V  10 lg d
where
LWA the sound power level of the moving source, in dB(A),
Q the number of vehicles/sources per hour,
v the speed (km/h),
d the distance from the receiver to the center of the haul road (m).
The equation in section F.2.5 of the standard mixes up emission and immission. In CadnaA however, emission and immission are always treated separately. When using moving
point sources (PWL-Pt) in CadnaA, the overall PWL of the line source is calculated
prior to the propagation (see chapter 2.1.1 "Common Input Data").
When using other equations to specify emission it is advisable to calculate the sound
power level PWL beforehand and to enter this as a calculated PWL directly. This applies,
for example, when using the -33 dB correction instead of -30 dB from the equation in
section F.2.5 of BS 5228.
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Chapter 6 - Calculation
6.2.9.5 BS 5228
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Obstacles within Area
Source do not Shield
Example
6
Area source with 2 buildings inside, option activated: sources with
free propagation (with all rays displayed)
With this option activated the result levels are calculated as if the obstacles
were not present (i.e. no screening effect).
Area source with 2 buildings inside,
option deactivated: sub-sources behind the buildings are screened,
sub-sources in front of buildings with free propagation (screened rays in RED)
With this option deactivated lower levels result at the receiver points due to
the screening effect of the obstacles inside. Nevertheless, for all other sources
(i.e. sources outside of the are source’s border) the obstacles inside cause always screening.
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Chapter 6 - Calculation
6.2.9.5 BS 5228
Temperature / rel.
Humidity
The air attenuation is calculated based on the temperature and relative
humidity. Intermediate frequency values result from linear interpolation. The
temperature specified serves also as the ambient temperature when
calculating the exhaust stack’s directivity.
Wind Speed for
Directivity (m/s)
The entered wind speed will be used in the calculation of the directivity of
chimneys (see chapter 2.2.1 "Sound Radiation from Chimneys or Stacks").
6
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Chapter 6 - Calculation
6.2.9.5 BS 5228
Additional Information
The propagation model in BS 5228 distinguishes three kinds of situations
with respect to ground attenuation. In each of these three situations the
calculation in CadnaA is based on the ground factor G as being entered on
the „Ground Absorption“ tab (see chapter 6.2.7).
•
Divergence & Ground
Absorption
geometrical divergence K’h for hard ground (G=0):
K 'h  20 lg r  8 dB
6
where r is the distance source-receiver
•
geometrical divergence K’s for soft ground (G=1):
K 's  25 lg r  1 dB
where r is the distance source-receiver (with r >= 25 m)
•
geometrical divergence for mixed ground (0 < G <1):
soft  G  K 's  K 'h 
For all three settings the conditions expressed in section F.2.3.2.1 regarding
the distance adjustments are respected.
BS 5228 states that in case of a barrier being present the screening effect and
the ground attenuation can just be combined for hard ground. Consequently,
the correction K’h is always used for the ground attenuation when a barrier is
intersecting the path.
Screening
BS 5228 specifies in section F.2.2.2.1 that for calculations of the noise level at
a distance of 1 metre in front of a façade a correction of +3 dB has to be
made.
Facade Effect
As already with CRTN, CadnaA does not apply this correction automatically,
however controlling its use by the string variable FACADE defined on the
memo-window of a receiver.
Please see chapter 6.2.10.6 "CRTN", section "Facade Effect", for details on
the procedure.
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6
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Chapter 6 - Calculation
6.2.9.6 Harmonoise
6.2.9.6
Harmonoise
6
When this option is activated the propagation calculation is performed in
third-octave band width (25 to 10000 Hz). In this case with a source
spectrum supplied in octave band width (31.5 to 8000 Hz), for all three thirdoctaves within an octave the same input data (PWL) is used. The result is
displayed just in octave band width.

Calculation in 1/3Octave Bands
The main effect from this setting is that the impact of air absorption is
more severe when calculating in third-octave band width resulting in a
lower receiver level, especially at higher frequencies.
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
for an example see chapter 6.2.9.5 "BS 5228"
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6
Sources in Building/
Cylinder do not shield
Chapter 6 - Calculation
6.2.9.6 Harmonoise
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.

In this case, prior to the calculation, a message will be displayed (dialog
Consistency Check) which enables to proceed with the operation
(button „Continue“).
This procedure is due to the fact that buildings and cylinders are treated as
open boxes within the calculation of propagation (despite they are displayed
as „closed“ objects, i.e. with roof, on the 3D-Special View).
6
With this option activated, sources located inside of the geometrical borders
of buildings or cylinders are not screened as if the obstacle were not present.
For sources outside, those obstacles are always screening and - if any - reflecting. This option enables to model e.g. sound radiating chimneys by using
point or line sources located inside the cylinder. In this case, the directivity
pattern of the chimney - whether entered or selected from the default
directivities - will not distorted by the cylinder’s screening edge.
Example
see manual „Introduction to CadnaA“, chapter 6.3 Directivity
Temperature / rel.
Humidity
The air attenuation is calculated based on the temperature and relative
humidity. Intermediate frequency values result from linear interpolation. The
temperature specified serves also as the ambient temperature when
calculating the exhaust stack’s directivity.
Harmonoise DLLVersion
After the first calculation using Harmonoise the version of the file PointToPoint.dll in the CadnaA-installation directory will be displayed.

The Harmonoise DLL presently implemented in CadnaA is of version
2.020.
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Chapter 6 - Calculation
6.2.9.6 Harmonoise
Harmonoise method applies a specific input data set for the meteorological
correction, not considering any statistical distribution for long-term
averaging. A proposal on how to handle the Harmonoise model to predict
long-term average levels see /3/, chapter 3.3.11.
Meteorology
Harmonoise offers five meteorological propagation classes depending on the
following parameters:
•
•
•
•
wind speed at 10 m above the ground, v (m/s) at z = 10 m,
wind speed component in the direction of sound propagation at 10 m
above the ground, u (z = 10 m),
cloud cover in octas (i.e. as a multiple of 1/8), and
time of the day (day/night).
6
Within the engineering model besides the five stability classes, eight distinct
wind directions (i.e. in steps of 45°), and three wind speed classes are applied.
In CadnaA, intermediate values are linearly interpolated.
The stability class addressing the vertical stability of the atmosphere can be
specified for the daily periods D/E/N separately. The five stability classes are
characterized by day/night and cloud cover /4/:
stability class
day/night, cloud cover
S1
day, 0/8 ... 2/8
S2
day, 3/8 ... 5/8
S3
day, 6/8 ... 8/8
S4
night, 5/8 ... 8/8
S5
night, 0/8 ... 4/8
From this a classification with respect to favorable or unfavorable
propagation conditions depending on wind direction (see below) can be derived (simplified from /5/):
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Chapter 6 - Calculation
6.2.9.6 Harmonoise
wind direction  (*1)
stability class
-90°
-45°
0°
45°
90°
S1: day, no clouds
S2: days, clouds 50%
S3: day, clouds 100%
S4: night, cloudy
6
S5: night, clear sky
(*1):
 is the angle between the wind direction and the direction of sound propagation
Note:
From the wind speed class and the stability class the inverse of the Monin-Obukhov
length 1/L results being used to predict the height difference h above the straight ray
path.
Caption:
very favorable
favorable
neutral
unfavorable
very unfavorable
Consequently, by class S1 a vertically very unstable atmospheric condition is
addressed („sunny day“), while class S5 models a stable condition („clear
night“). A neutral atmospheric condition would be represented by class S3
(„heavily clouded/overcast“).
Wind Direction (°) D/E/N
The wind direction is the direction from which a wind originates (with 0° being North wind, i.e. wind blowing from North, with 180° being South wind
etc.).
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Chapter 6 - Calculation
6.2.9.6 Harmonoise
The wind speed refers to a height of 10 m above ground. The following wind
speed classification is used /4/:
wind speed class
wind speed at 10 m
above ground
v (z=10 m)
W1
0 ... 1 m/s
W2
1 ... 3 m/s
W3
3 ... 6 m/s
W4
6 ... 10 m/s
W5
> 10 m/s
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Wind Speed (m/s) D/E/N
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138
6
Chapter 6 - Calculation
6.2.9.6 Harmonoise
Additional Information
Default Calculation
Settings used by
Harmonoise-DLL
6
The calculations when using Harmonoise method are performed by the
dynamic link library PointToPoint.dll in the CadnaA installation directory. This DLL (Dynamic Link Library) represents the so-called
„Engineering Model“ for industrial noise sources within the Harmonoise
project /3/. The calculation settings of the DLL used per default have been
fixed in accordance with CSTB (Centre Scientifique et Technique du
Bâtiment, Grénoble/France) which has implemented the engineering
propagation model.
The following options are applied:
•
EnableAveraging option: enabled
•
EnableScattering option: not enabled
•
For all three third-octaves within an octave the same input data is used
(i.e. spectrum is a step function).
•
The ground factor G and the absorption coefficient Alpha are
transformed by linear interpolation to an air resistivity according to:
 for the ground factor G (as entered on the Configuration dialog,
„Ground Absorption“ tab, see chapter 6.2.7, and for the object
„Ground Absorption“, see chapter 3.6):
ground factor G
airflow resistivity 
(kNsm-4)
0
20000
0.33
1000
0.50
600
0.67
400
1.00
50
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6.2.9.6 Harmonoise
6 139
 and for the absorption coefficient Alpha of buildings and barriers (see
Chapter 3 - Obstacles):
absorption coefficient
airflow resistivity 
Alpha
(kNsm-4)
0
20000
0.25
1000
0.50
600
0.75
400
1.00
50
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6
Batch Processing
Chapter 6 - Calculation
6.2.9.6 Harmonoise
Different meteorological configurations for a distinct situation can be
processed automatically. The procedure to be followed consists of the
following:
•
the situation file with several receiver points (in the example below:
meteo.cna),
•
the macro-file specifying the configuration of calculation and the results
to be exported (in the example below: meteo.cnm).
•
The macro-file is loaded into CadnaA via menu File|Open. Select the
option „All Files“ from the list box „File Type“ to select the cnm file.
•
Upon opening of the file the batch processing start automatically and
saves the results to a text file with file extension *.log (in the example
below: meteo.log).
6
 Examples\05_Immissions\Harmonoise
File Structure of
meteo.cnm
An example file is provided. Follow the procedure as described above.
The macro-file meteo.cnm makes use of the keywords CalcConf and ObjAtt
(see CadnaA-manual „Attributes, Variables, and Keywords, chapter 3.2 and
chapter 3.20).
The file meteo.cna is loaded by the command: #(LoadFile, meteo.cna). The
next line specifies the column headings. The keyword #(ObjAttAll, 02000000,
ID) establishes a dynamic link to the name of each receiver (see CadnaAmanual „Attributes, Variables, and Keywords, chapter 3.21). The four subsequent lines define the configuration settings for meteorological classes S1 to
S4 (of Harmonoise), start the calculation at receivers (using the keyword
#(CalcImm)), and retrieve the results for level LP1 (using the keyword
#(ObjAttAll)). The command #(QuitAtOnce) closes the file saving the result
file meteo.log.
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Chapter 6 - Calculation
6.2.9.7 Concawe
6.2.9.7
Concawe
6
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Obstacles within Area
Sources do not shield
Example
Area source with 2 buildings inside, option activated: sources with
free propagation (with all rays displayed)
With this option activated the result levels are calculated as if the obstacles
were not present (i.e. no screening effect).
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Chapter 6 - Calculation
6.2.9.7 Concawe
6
Area source with 2 buildings inside,
option deactivated: sub-sources behind the buildings are screened,
sub-sources in front of buildings with free propagation (screened rays in RED)
With this option deactivated lower levels result at the receiver points due to
the screening effect of the obstacles inside. Nevertheless, for all other sources
(i.e. sources outside of the are source’s border) the obstacles inside cause
always screening.
Sources in Building/
Cylinder do not shield
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.

In this case, prior to the calculation, a message will be displayed dialog
Consistency Check) which enables to proceed with the operation
(button „Continue“).
This procedure is due to the fact that buildings and cylinders are treated as
open boxes within the calculation of propagation (despite they are displayed
as „closed“ objects, i.e. with roof, on the 3D-Special View).
With this option activated, sources located inside of the geometrical borders
of buildings or cylinders are not screened as if the obstacle were not present.
For sources outside, those obstacles are always screening and reflecting. This
option enables to model e.g. sound radiating chimneys by using point or line
sources located inside the cylinder.
In this case, the directivity pattern of the chimney - whether entered or
selected from the default directivities - will not distorted by the cylinder’s
screening edge.
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Chapter 6 - Calculation
6.2.9.7 Concawe
see manual „Introduction to CadnaA“, chapter 6.3 Directivity
Example
The air attenuation is calculated based on the temperature and relative
humidity. Intermediate frequency values result from linear interpolation. The
temperature specified serves also as the ambient temperature when calculating the exhaust stack’s directivity.
Temperature / rel.
Humidity
In the CONCAWE propagation model the meteorological correction is
named „attenuation factor for meteorological effects K4“ /1/. The
attenuation is a function of frequency, distance, and meteorological category.
Meteorology
With non-spectral sources CadnaA applies the correction K4 independent
of frequency as stated in CONCAWE, appendix II, section 2. Thus, the
spectral K4 at the entered frequency (500 Hz per default) is not used.

Despite the specification in CONCAWE, appendix II, not to use the
attenuation curves for receiver distances below 100 m, in CadnaA the
value of K4 for d<100 m is linearly interpolated to 0 dB at the source
location.
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6
Stability Class D/E/N
Chapter 6 - Calculation
6.2.9.7 Concawe
The assessment of atmospheric temperature gradient is replaced by use of
Pasquill Stability Categories A to G (for periods D/E/N separately). The
definition of the categories depends on wind speed, time, and cloud cover:
Wind Speed *
m/s
6
Day Time,
Incoming Solar Radiation
(mW/cm²)
> 60
30-60
< 30
Overcast
1 hour
before
Sunset or
after
Sunrise
<=1.5
A
A-B
B
C
2.0 - 2.5
A-B
B
C
3.0 - 4.5
B
B-C
5.0 - 6.0
C
> 6.0
D
Night-Time,
Cloud Cover
(octas)
0-3
4-7
8
D
F or
G**
F
D
C
D
F
E
D
C
C
D
E
D
D
C-D
D
D
D
D
D
D
D
D
D
D
D
D
D
Notes:
*: wind speed is measured to the nearest 0.5 m/s
**: category G is restricted to night-time with less than 1 octa of cloud and a wind speed of less
than 0.5 m/s
Based on literature, category A represents a strong lapse condition (large
temperature decrease vs. height), category G a temperature inversion
observed early on a clear morning. Categories E and F apply to slight
inversions. However, inversion conditions, particularly those over water, are
highly variable and not easy to predict. The acoustical effect depends on
additional factors (e.g. geometry).
From this classification six new meteorological categories have been defined,
based an a combination of Pasquill Stability Categories (representing the
temperature gradient) and vector wind speeds (v (z=10 m) in m/s). The
effect on the attenuation is indicated by the arrow.
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6.2.9.7 Concawe
6 145
Pasquill Stability
Category
Meteorological
Category
A, B
C, D, E
F, G
1
v < -3.0
-
-
2
-3.0 <= v <-0.5
v <= -3.0
-
3
-0,5 <= v < + 0.5
-3.0 <= v < -0.5
v < -3.0
4 (*1)
+0.5 <= v <+3.0
-0.5 <= v < +0.5
-3.0 <= v < -0.5
5
v >= +3.0
+0.5 <= v < +3.0
-0.5 <= v < +0.5
6
-
v >= +3.0
+0.5 <= v < +3.0
(*2)
6
Notes:
*1: category with assumed zero meteorological influence
*2: For speeds v >= +3.0 also category 6 is assumed.

In CadnaA, the Pasquill Stability Category D at wind speed 0 m/s is
selected by default, resulting in the meteorological category 4 with a
correction K4=0 dB.
The wind direction is the direction from which a wind originates (with 0°
being North wind, i.e. wind blowing from North, with 180° being South
wind etc.).
Wind Direction (°) D/E/N
CONCAWE-method does not specify at what height the wind direction and
speed shall be assessed.
Wind Speed (m/s) D/E/N

The commonly used height for evaluation of wind speeds in
meteorology is 10 m above ground (plus further criteria regarding
nearby obstacles etc.).
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6
Interpolate
Meteorological Category
Chapter 6 - Calculation
6.2.9.7 Concawe
As the velocity vector of the wind in source-receiver direction is relevant for
the calculation of the meteorological correction level steps may result
between categories. This option causes to smoothen the noise contours at the
limits of areas with different meteorological categories by interpolation.
Example
6
horizontal grid from a point
source with meteo settings:
- stability class: A
- wind direction: 180°
- wind speed: 5.0 m/s
option „Interpolate
meteorological Category“
deactivated
as above
option „Interpolate
meteorological Category“
activated
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Chapter 6 - Calculation
6.2.9.7 Concawe
Different meteorological configurations for a distinct situation can be
processed automatically. The procedure to be followed consists of the
following steps:
•
the situation file with several receiver points (*.cna),
•
the macro-file specifying the configuration of calculation and the results
to be exported (*.cnm).
•
The macro-file is loaded into CadnaA via menu File|Open. Select the
option „All Files“ from the list box „File Type“ to select the cnm-file.
•
Upon opening of the file the batch processing start automatically and
saves the results to a text file with file extension *.log.
An example file is provided. The settings in the example refer to the method
„Harmonoise“. Please see chapter 6.2.9.6 for more details.
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 Examples\05_Immissions\Harmonoise_Concawe
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Chapter 6 - Calculation
6.2.9.7 Concawe
Additional Information
Ground Attenuation K3
6
The ground attenuation K3 is controlled in CadnaA via the „Default
Ground Factor“ G specified on tab „Ground Absorption“ (see chapter
6.2.7). With the default ground factor G=0 reflective ground is assumed
(leading to K3=-3 dB), while with a default ground factor G>0 absorbing
ground is considered. The object „Ground Absorption“ can be used to
model mixed ground (with G=0 or G>0). In this case, CadnaA just evaluates
the ray’s path length across the absorptive ground (see CONCAWE-report,
section 5.1.3).

Meteorological
Correction K4
Despite the specification in CONCAWE, appendix II, not to use the
attenuation curves for receiver distances below 100 m, in CadnaA the
value of K3 for d<100 m is linearly interpolated to 0 dB at the source
location.
In CONCAWE, the so-called „vector wind velocity“ for each ray path based
on the entered overall wind velocity and direction is evaluated (see chapter
2.5 of /1/) considering the angle between the entered wind direction and the
ray‘s path. Thus, the relevant speed for K4 can be smaller than the specified
wind speed resulting in a different meteo category. For downwind the cosine
is positive, for upwind negative.
Example 1: Relevant wind speed in a downwind situation
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6.2.9.7 Concawe
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6
Example 2: Relevant wind speed in an upwind situation
The function for gamma using the grazing angle  is limited to >=0 (i.e. no
negative values for ), Thus, the function plotted in figure 9 of CONCAWE
report is in CadnaA assumed to end at =0 asymptotically (as a specification
is missing).
Source/Receiver Height
Correction K5
In the CONCAWE-report, section 2.7, it says:
Barrier Attenuation K6
„The presence of a discrete barrier may reduce ground effects and it is
proposed that this be covered by recalculating K5 based an the barrier height
and barrier-receiver distance.“
Furthermore, it says in section 5.1.6:
„This is not, however, necessary if the barrier is a topographical feature.“
This proposal is not respected in CadnaA as it causes level jumps due to
different path length differences.
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Distance Source-Receiver
6
Type of Wind & Wind Data
Chapter 6 - Calculation
6.2.9.7 Concawe
In CONCAWE, it is unclear what the mentioned „distance d“ exactly means,
the 2D or the 3D distance. On page 8 of the CONCAWE-report it says “d
source – receiver distance” (i.e. not specifying whether 2D or 3D distance is
meant). This has, with respect to the different attenuation terms, the
following consequences with regard to the implementation in CadnaA:
•
In CONCAWE, chapter 5.1.1, the attenuation term K1 is based clearly on
3D distance (CadnaA uses 3D distance for K1).
•
In CONCAWE, chapter 5.1.4, regarding the attenuation term K4 nothing
is said whether to use 2D or 3D distance (CadnaA uses 2D distance).
•
In CONCAWE, chapter 5.1.5, the attenuation term K5 in the equation
for psi the distance d must be the 2D distance (as 3D distance does not
make sense).
CONCAWE does not specify what kind of wind regarding stability class,
wind direction and wind speed is to be used. For example, it does not say
whether the wind data should be based on average values, on peak values, or
on the „representative/dominating wind“ at a location or in an area. Further,
it is not said in CONCAWE at what height the wind direction and speed shall
be assessed.
Furthermore, CONCAWE does not address the objective on how to proceed
in order to assess a long-term average level based on several distinct wind
situations.
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Chapter 6 - Calculation
6.2.9.8 NMPB-Industry 2008
6.2.9.8
NMPB-Industry 2008
6
Three options for lateral diffraction are available for selection:
•
none: No lateral diffraction considered, just the direct path sourcereceiver is evaluated.
•
only one object: Lateral diffraction is not calculated if more than one
object intersects the line connecting the source to the receiver point.
•
some objects: The two shortest possible convex rays around the
arrangement of objects are determined and used for the calculation of the
lateral diffraction.
Lateral Diffraction
This setting defines the distance between source and receiver for which
lateral diffraction is taken into account. The default value is 1000 m.
if Distance smaller (m)
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Obstacles within Area
Sources do not shield
see chapter 6.2.9.7 "Concawe"
Example
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6
Sources in Building/
Cylinder do not shield
Chapter 6 - Calculation
6.2.9.8 NMPB-Industry 2008
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.
For further details and an example see chapter 6.2.9.7 "Concawe".
6
Temperature / rel.
Humidity
The air attenuation is calculated based on the temperature and relative
humidity. Intermediate frequency values result from linear interpolation. The
temperature specified serves also as the ambient temperature when calculating the exhaust stack’s directivity.
Meteorology
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
List Box / Locations
For calculations using NMPB 2008 the following items from the list box apply:
•
•
•
•
(default): favorable conditions D/E/N = 50/75/100%
(favorable): favorable conditions D/E/N = 100/100/100%
(homogène): favorable conditions D/E/N = 0/0/0%
XXX (2) and XXX (3) with „XXX“ representing a French town and
region: data of the percentage of favorable conditions for two (2: D, N) or
three time periods (3: D, E, N) according to NMPB 2008.
For further details see chapter 6.2.10.4 "NMPB-Routes 2008".
Use reference DLL
This option is deactivated by default. In this case, CadnaA code is used for
the calculation implemented based on the printed documentation of NMPB
2008.
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6.2.9.8 NMPB-Industry 2008
6 153
By activating this option the later released, but officially provided reference
DLL (developed by the French consortium) is used for the calculation.
This option requires to copy the reference DLL (PropagationNMPB.dll) into
the respective CadnaA installation directory. The DLL is not part of the
CadnaA installation procedure and is, therefore, distributed separately.
6
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Chapter 6 - Calculation
6.2.9.8 NMPB-Industry 2008
6
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Chapter 6 - Calculation
6.2.9.9 CNOSSOS-EU
6.2.9.9
CNOSSOS-EU
6
Three options for lateral diffraction are available for selection:
•
none: No lateral diffraction considered, just the direct path sourcereceiver is evaluated.
•
only one object: Lateral diffraction is not calculated if more than one
object intersects the line connecting the source to the receiver point.
•
some objects: The two shortest possible convex rays around the arrangement of objects are determined and used for the calculation of the lateral
diffraction.
Lateral Diffraction
This setting defines the distance between source and receiver for which lateral diffraction is taken into account. The default value is 1000 m.
if Distance smaller (m)
When this option is active, any obstacle (e.g. buildings, foliage, barriers etc.)
located within area sources (including parking lots and optimizable sources)
provide no screening for any sub-source of that area source.
Obstacles within Area
Source do not Shield
(for an example see chapter 6.2.9.1)
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6
Sources in Building/
Cylinder do not shield
Chapter 6 - Calculation
6.2.9.9 CNOSSOS-EU
By default, a screening effect results for sources inside buildings and cylinders
as the outer walls act as barriers.
(for more information on this option see chapter 6.2.9.1)
Temperature / rel.
Humidity
The air attenuation is calculated based on the temperature and the relative
humidity according to ISO 9613-1. Intermediate frequency values result from
linear interpolation. The temperature specified serves also as the ambient
temperature when calculating the exhaust stack’s directivity.

6
Meteorology
The octave band at center frequency of 31.5 Hz is excluded explicitly
from the CNOSSOS-EU calculation model.
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
For further details on this dialog, see chapter 6.2.10.4, section "Meteorology".

No hint is possible what percentage may apply to an unknown location
when just a general description of the local orography is available.
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Chapter 6 - Calculation
6.2.9.10 HJ 2.4 (2009)
6.2.9.10
HJ 2.4 (2009)
6
Three options for lateral diffraction are available for selection:
•
none: No lateral diffraction considered, just the direct path sourcereceiver is evaluated.
•
only one object: Lateral diffraction is not calculated if more than one
object intersects the line connecting the source to the receiver point.
•
some objects: The two shortest possible convex rays around the arrangement of objects are determined and used for the calculation of the lateral
diffraction.
Lateral Diffraction
This setting defines the distance between source and receiver for which lateral diffraction is taken into account. The default value is 1000 m.
if Distance smaller (m)
The air attenuation is calculated based on the temperature and the relative
humidity according to ISO 9613-1. Intermediate frequency values result from
linear interpolation. The temperature specified serves also as the ambient
temperature when calculating the exhaust stack’s directivity.
Temperature / rel.
Humidity
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6.2.9.10 HJ 2.4 (2009)
6
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Chapter 6 - Calculation
6.2.10 Road Tab
6.2.10
6 159
Road Tab
Information on the calculation options for the following standards or
guidelines for industry can be found in the German version of the CadnaA
reference manual:
 RVS 4.02 (Austria)
 StL-86 (Switzerland)
 DIN 18005 (1987, Germany)
The subsequent table lists the main characteristics of the propagation models
for road noise as treated in the chapters explaining the configuration options.
A special focus is put to the type of modeling being used for the various attenuating effects in sound propagation.
Table „Propagation
Models Road“
A further table describes the properties of obstacles and special-objects in
CadnaA with each propagation model.
Table „Obstacles and
Special-Objects“
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Chapter 6 - Calculation
6.2.10 Road Tab
Propagation Models Road
6
No
Option or
Propagation
Effect
Standard / Guideline
1
calculation using
A-weighted levels
yes
yes
2
spectral
calculation
no
no
3
geometrical
attenuation
(divergence)
line source propagation (includes air absorption)
LAeq/LAFmax: line/point
source propagation
4
attenuation by
air absorption
considered within the geometrical attenuation
not considered
5
handling of ground
reflections
not by image sources, but by an algorithm considering ground attenuation and meteorological effects in common (see below)
concept of reflection planes
6
handling of
reflections
at obstacles
just up to 1st order of reflection, higher orders of reflection applying a „Correction for multiple Reflections“,
in CadnaA optionally: calculation to up the 20th order, condition for reflection considers
obstacle’s size and absorption coefficient/reflection loss of the reflector
see RLS-90
7
attenuation due to
ground effect
(ground
attenuation)
for A-weighted levels (not applying ground factor G)
soft or hard ground only
(combined with screening)
8
attenuation due
to screening
(at objects)
single and double diffraction based on the path length difference of the direct path via the
obstacles, screening effect does not depend on wavelength (as just for A-weighted levels),
negative path difference causes no screening
concept of
effective height
9
handling of
lateral diffraction
not considered, in CadnaA optionally available
not considered
10
handling of
multiple obstacles
in ray path
based on the path length difference of the direct path across all obstacles („ribbon band
method“)
using the most efficient screen
11
attenuation due
to screening
(terrain)
screening by terrain not treated explicitly,
In CadnaA the algorithm for multiple screening objects is applied.
as with multiple screens
12
handling of
meteorological
effects (wind)
not treated explicitly as being part of the ground attenuation (meteorological correction is
part of the screening calculation), in CadnaA optional application of Cmet accord. to ISO
9613-2, with calculations acc. to VBUS: applies Cmet with C0,D/E/N=2/1/0 dB
not available
13
attenuation due to
foliage
not considered, in CadnaA optionally accord. to VDI 2714
not available
14
attenuation due to
built-up areas
not considered, in CadnaA optionally accord. to VDI 2714
not available
RLS-90 (1990)
Nordic (1996)
REMARK: „acoustical Transparency“ of buildings not available
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Chapter 6 - Calculation
6.2.10 Road Tab
Standard / Guideline
NMPB (1996)
CRTN
TNM
No
Czech Method
SonRoad
NMPB (2008)
CNOSSOS-EU
yes
yes
yes
yes
yes
yes
yes
1
yes (octaves, 125
to 4000 Hz)
no
yes
(1/3 octaves)
no
yes
(1/3 octaves)
yes (1/3 octaves,
100 to 5000 Hz)
yes (for octaves
63 Hz to 8000
Hz, + 31.5 Hz
2
point source
propagation
(4r2)
in CadnaA:
segmented
line source
point source
propagation
(4r2)
point source
propagation
(4r2)
point source
propagation
(4r2)
point source
propagation
(4r2)
point source
propagation
(4r2)
3
yes (for 15°C and
70% r.h.)
not considered
acc. ISO 9613-1
(e.g. 20°C, 50%)
combined with
ground att.
acc. ISO 9613-1
(for 15°C, 70%)
acc. ISO 9613-1
(for 15°C, 70%)
yes (acc. to ISO
9613-1)
4
algorithmic, not
by image sources
algorithmic, not
by image sources
complex ground
impedance
algorithmic, not
by image sources
complex ground
impedance
algorithmic, not
by image sources
algorithmic incl.
ground absorp.
5
no mult. reflect.
correction by
default, optional
in CadnaA
not using image
sources (optional
in CadnaA)
in CadnaA: via
absorption
coeff./reflect.
loss of reflector
see RLS-90
using complex
reflection factor
& phase relation
no mult. reflect.
correction by
default, optional
in CadnaA
yes
6
spectral model
(for favorable:
ISO 9613-2, for
homogeneous
specific)
empirical
correction
via transfer table
from airflow
resistivity to
ground factor G
combined ground
and meteorological correction
via transfer table
from airflow
resistivity  to
ground factor G
spectral model
(for favorable:
ISO 9613-2, for
homogeneous
specific)
homogeneous &
favorable conditions using
ground factor G
7
based on path
length difference
based on path
length difference
diffraction model
using Fresnelzones &
complex ground
impedance
see RLS-90
using path length
difference (ISO
9613-2), ground
reflection based
on Fresnel-zones
based on path
length difference
single & double
diffr., includes
ground effect,
using image
source method
8
not considered
not considered
not considered
see RLS-90
not considered
not expressively
considered
yes, at 2 vertical
edges (incl.
ground abs.)
9
see RLS-90
inverse
energetic sum of
individual barrier
corrections
via path length
difference
see RLS-90
via path length
difference
via path length
difference
via path length
difference
(convex hull)
10
see RLS-90
as with multiple
screens (no lateral
diffraction)
as with multiple
screens
see RLS-90
as with multiple
screens
as with multiple
screens
see ISO 9613-2
11
for homogeneous & favorable prop. cond.,
energetic addition
not available
not available
not available,
optional in
CadnaA: using
Cmet
for homogeneous & favorable prop. cond.
(see NMPB)
for homogeneous & favorable prop. cond.,
energetic addition
for homogeneous & favorable prop. cond.,
energetic addition
12
not available
not available
in CadnaA not
available
not available
available
not available
not available
13
not available
not available
in CadnaA not
available
not available
not available
not available
not available
14
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Chapter 6 - Calculation
6.2.10 Road Tab
Obstacles and Special-Objects
6
No
Object Type/
Option
Standard / Guideline
1
building
single and multiple diffraction for edges parallel to the ground based on the shortest path
difference, no lateral diffraction via the vertical edges by default, no reflection or by input
of absorption coefficient/reflection loss, no acoustical transparency
see RLS-90
2
cylinder
single and multiple diffraction for edges parallel to the ground based on the shortest path
difference, no lateral diffraction by default, no reflection or by input of absorption coefficient/reflection loss, reflection up to 1st order
see RLS-90
3
barrier
single and multiple diffraction for edges parallel to the ground based on the shortest path
difference, no lateral diffraction by default, no reflection or by input of absorption coefficient/reflection loss
see RLS-90
4
floating
barrier
no diffraction via the lower edge (screening edge without diffraction),
otherwise see barrier
see RLS-90
5
barrier with
cantilever
cantilever is totally absorbing (no reflection), calculation of the path length difference valid
for receivers/grid points outside and below the cantilever, otherwise see barrier
not available (due to „effective
height“ concept)
6
bridge plate
diffraction calculation for horizontal plate only (inclined plate approximated to horizontal
plate), screening calculation valid for sources above the bridge plate (diffraction downwards), no reflection-induced level increase below the bridge plate (as ground is not modeled by mirror sources)
see RLS-90
7
embankment
acts as a double barrier, diffraction for direct path (without lateral diffraction), no absorptive/reflective properties
see RLS-90
8
ground
absorption area
not relevant (generalized ground attenuation)
in CadnaA: using ground factor G (soft/hard only)
9
built-up area/
foliage
not relevant by default, optionally accord. to VDI 2714
not available
10
3D-reflector
screening calculation based on the shortest path length difference, plus two lateral paths,
diffraction can be suppressed for up to 32 edges, no reflection or by input of absorption
coefficient/reflection loss, reflection up to 1st order, no summation of diffraction effects
via multiple edges, no multiple diffraction
not available
(due to „effective height“ concept)
11
self screening
additional feature in CadnaA: causes screening effect downwards, additional with left/
right available (fixed to the road, screening just for the own road source)
see RLS-90
12
additional width/
parapet L/R
parapet left/right available, parapet length can be restricted using station marks, additional
width just for ground absorption with no effect with RSL-90
see RLS-90
RLS-90
Nordic (1996)
REMARK: The embankment is not considered in the triangulation!
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Chapter 6 - Calculation
6.2.10 Road Tab
Standard / Guideline
NMPB (1996)
CRTN
TNM
Czech Method
No
SonRoad
NMPB (2008)
CNOSSOS-EU
see RLS-90
see RLS-90
numerical
diffraction model
see RLS-90
numerical
diffraction model
see RLS-90
see RLS-90, but
for homogeneous & favorable conditions
1
see RLS-90
see RLS-90
see above
see RLS-90
see above
see RLS-90
for homogeneous & favorable conditions
2
see RLS-90
see RLS-90
see above
see RLS-90
see above
see RLS-90
see RLS-90, but
for homog. &
favorable cond.
3
see RLS-90
see RLS-90
not available
see RLS-90
not available
see RLS-90
see RLS-90
4
not available
not available
not available
not available
not available
not available
see RLS-90
5
see RLS-90
see RLS-90
available
see RLS-90
available
see RLS-90
see RLS-90
6
see RLS-90
see RLS-90
available
see RLS-90
available
see RLS-90
see RLS-90
7
using ground factor G (for favorable and
homogeneous)
empirical ground
correction (chart)
from ground factor G transferred
to airflow
resistivity 
not relevant
from ground factor G transferred
to airflow
resistivity 
using ground
factor G (for
favorable and
homogeneous)
yes, using ground
factor G (for
favorable and
homogeneous)
8
not available
not available
not available in
CadnaA (for the
time being)
not available
not available in
CadnaA (for the
time being)
not available
no effect
9
see RLS-90
see RLS-90
not available (not
compatible with
TNM diffraction
model)
see RLS-90
not available
not available
not available
10
see RLS-90
see RLS-90
not available (not
covered by TNM
diffract. model)
see RLS-90
available
see RLS-90
see RLS-90
11
see RLS-90
see RLS-90
available (used to
apply correct
road width)
see RLS-90
available
see RLS-90
see RLS-90
12
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Chapter 6 - Calculation
6.2.10 Road Tab
6
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Chapter 6 - Calculation
6.2.10.1 RLS-90
6.2.10.1
6 165
RLS-90
6
Dialog Configuration, tab „Road“ for RLS-90
(with option „strictly accord. to RLS-90“ deactivated)
With the check box „Strictly according to RLS-90“ activated, CadnaA
calculates using the following settings:
•
•
•
•
•

only the first-order reflections, irrespective of the order of reflection
specified on the „Reflection“ tab,
no lateral diffraction at obstacles,
no attenuation due to foliage and built-up areas,
no meteorological correction, and
the two outermost lanes of a road are calculated as separate line sources
with a height of 0.5 m above road.
All other settings made on the „Reflection“ tab, "Conditions for
Calculation of Reflection", such as the search radius for reflecting
objects, will apply even when the option „Strictly according to RLS-90“
is activated (see chapter 6.2.8 "Reflection Tab").
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RLS-90
166
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Chapter 6 - Calculation
6.2.10.1 RLS-90
Calc exactly one
reflection order
With this option deactivated the maximum order of reflection is specified via
the „Reflection“ tab (see chapter 6.2.8 "Reflection Tab").
No Lateral Diffraction
When this option is deactivated the lateral diffraction will be considered
which is normally not the relevant to the receiver level due to the extension
of the road sources (line sources) in normal situations.
6
no lateral diffraction by default,
option „Strictly according
to RLS-90“ activated (short road section)
No Housing
Attenuation
with lateral diffraction, option „Strictly
according to RLS-90“ and „No Lateral Diffraction“ deactivated
By default, the attenuation by built-up areas is not considered by RLS-90.
When this option is deactivated the CadnaA-object „Built-Up Area“ causes a
screening effect.

The housing attenuation DG is calculated accord. to VDI 2714 (see
chapter 3.5 "Built-Up Areas and Foliage"). This value is not displayed
on the calculation protocol in a separate column (see CadnaA-manual
„Attributes, Variables, and Keywords“, chapter "Chapter 6 - Protocol
Abbreviations").
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Chapter 6 - Calculation
6.2.10.1 RLS-90
By default, the attenuation by foliage is not considered by RLS-90. When this
option is deactivated the CadnaA-object „Foliage“ causes a screening effect.

The attenuation due to foliage DG is calculated accord. to VDI 2714
(see chapter 3.5 "Built-Up Areas and Foliage"). This value is not
displayed in a separate column on the calculation protocol.
By default, the center lines of the outermost lanes of a road are the emission
lines in RLS-90 (at a height of 0.5 m). When this option is deactivated just the
road’s center line represents the emission line.
vertical grid, perpendicular to the road’s
axis: option „Strictly according to RLS-90“
activated
Calc outer Lanes
separately
6
vertical grid: option „Strictly according to
RLS-90“ and „Calc outer Lanes separately“
deactivated
No meteorological correction is established by RLS-90. In CadnaA,
nevertheless, the meteorological effect can be considered by deactivation of
this option. In this case, the settings on the list box „Meteorology“ on the
„Industry“ tab are relevant.

No Foliage
Attenuation
No Meteorology
(Cmet see Industry)
The value of Cmet will be calculated according to ISO 9613-2. This value
is not displayed on the calculation protocol in a separate column.
see also: chapter 6.2.9.1 "ISO 9613", section "Meteorology"
relevant for Germany only!
The German guideline VBUS is selectable on the „Road“ tab with RLS-90
selected. The main modifications compared to the original procedure from
RLS-90 are:
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Calculation accord. to
VBUS
168
6
6
Displaying the value of
Cmet
Chapter 6 - Calculation
6.2.10.1 RLS-90
•
The setting for lateral diffraction is not possible any longer.
•
The calculation includes the meteorological correction Cmet (C0 for Day/
Evening/Night is 2/1/0 dB).

When not considering Cmet and with the same emission D/E/N a level
difference between Lden and Ln of 6.395 dB results. Since Cmet is automatically taken into account in CadnaA, the difference is usually
smaller than this value.
•
From MDTD values the number of vehicles per hour M (Day/Evening/
Night) are calculated according to VBUS (different from RLS-90).
The value of Cmet when calculating road noise accord. to RLS-90 can be displayed for raids with a road width of 0 m. Different values result for the two
emission lines of roads with a finite road width (the values of which, however, cannot be displayed using the procedure described in the following).
Proceed as follows:
•
First, deactivate the option „No Meteorology (Cmet see Industry)“ and
enter - for example - the following values for C0 on the „Industry“ tab:
D/E/N = 3/2/1 dB (for ISO 9613).
•
Activate the option „Write Protocol“ on the Calculation|Protocol
menu.
•
Start the calculation by clicking on the pocket calculator symbol on the
toolbar.
•
Open the protocol
„Print“|Preview“.
via
Calculation(|Protocol
menu,
button
CadnaA - Reference Manual
Chapter 6 - Calculation
6.2.10.1 RLS-90
•
When subtracting the individual attenuation terms from the emission
value you will appreciate that not the receiving level as shown results, but
that for every segment a difference remains.
•
In order to display this difference on the protocol the road source is converted into a line source (via the dialog Modify Objects|Convert to,
„Road“ into „line Source“).
6 169
With this, the emission parameter will be converted according to:
LwA "  Lm , E  19.2 dB
As the source height of the road is 0.5 m above ground, the line source needs
to get lifted up to 0.5 m first.
•
Open again the dialog Modify Objects|Modify Attribute for the object
„Line Source“ and click OK.
•
On the dialog Modify Attribute, select the attribute HA form the list box
and enter for „Arithmetic|New Value“ 0.5 m.
After click on OK the relative height of the line sources is set to 0.5 m.
•
Start the calculation by clicking on the pocket calculator symbol once
more.
•
Open the protocol (Calculation|Protocol menu, button „Print“|Preview“).
The values for Cmet displayed on the protocol are those relevant for the road
noise calculation. The receiver level and the further attenuation terms displayed on the protocol are, however, not relevant as the result from ISO
9613-2 and not from RLS-90.
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Chapter 6 - Calculation
6.2.10.1 RLS-90
6
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Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
6.2.10.2
Nordic Prediction Method (1996)
6
Dialog Configuration, tab „Road“ for Nordic Prediction Method (1996),
option „Calc maximum Pass-By-Level“ activated
With this option deactivated the maximum order of reflection is specified via
the „Reflection“ tab (see chapter 6.2.8 "Reflection Tab").
Calc exactly one
Reflection Order
see also 2.4.3 Nordic Prediction Method 1996
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.5 m). As in NPM just the road’s center line is the emission line, this option has to be deactivated.

When active, the emission level of each outer lane is -3 dB compared
with the road‘s axis being the emission line. The total emitted sound
power of the entire road is, however, the same in both cases (see chapter
6.5 "Calculation Protocol").

According to NPM, when screening occurs, the source location for
receivers behind the barrier is shifted to the barrier’s top edge.
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Calc outer Lanes
separately
172
6
Calc maximum PassBy-Level
Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
The A-weighted maximum sound pressure level LAFmax is an additional
descriptor of noise from road traffic in Nordic Prediction Method /73/. The
different corrections are calculated in complete analogy with those of the Aweighted equivalent continuous sound pressure level LA,eq with the one
exception that the shortest distance source-receiver is used instead of the
distance of calculation.
To calculate maximum levels, CadnaA moves a point source along each road
according to its speed and specified sampling interval. The source is starting
from either ends of the road due to the two emission lines representing the
road where different corrections may apply (e.g. gradient correction). The
maximum level for this point source for each position with the specified
sound power level and length is calculated.
6
LAFmaxX%
Enter the percentage of vehicles X% exceeding the calculated maximum level
LAFmax (default value: 5%). For details of the calculation see chapter 2.4.3.
Sampling Interval (s)
In order to determine the highest level, CadnaA shifts the source along the
road in steps based on the sampling interval (in seconds). The default value
for the sampling interval is 0.1 seconds. Consequently, the resulting distance
difference between two source positions is:
s  v  tsampling 
1000
3600
where
s: distance steps (m)
v: speed (km/h), as entered on dialog Road for „Autos“
t: sampling interval (s)
Example
The maximum level for the road is calculated using the default sampling
interval of 0.1 seconds. The maximum speed for autos is 100 km/h resulting
in a sampling distance of:
s  100  0.1 
1000
 2.78 m
3600
The stated maximum level is the maximum level from all sub-sources.
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Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
This option enables to calculate the number of events NATd/NATn above
the entered threshold level from the hourly traffic counts (for details of the
prescription see chapter 2.4.3).
Calculation of
Numbers above
Threshold (NATs)
With just the option „Calc maximum Pass-By-Level“ active a threshold level
of 70 dB(A) is applied always. By activating this option any other threshold
level can be entered.
Further, the following additional settings are required:
•
The evaluation parameters NATd (for Day) and NATn (for Night) are
selected, e.g. as 3rd and 4th evaluation parameters (see chapter 6.2.5.
•
The length of the evaluation periods Day (e.g. 16 h) and Night (e.g. 8 h)
periods has to be set on the „Reference Time“ tab by entering the letters
D/N for the respective hours (see chapter 6.2.4). This holds especially
when using diurnal patterns as road traffic figures.

When entering the emission level LAeq*,10m directly neither the
maximum Pass-By-Level, nor NATs can be calculated.
When this option is activated, the shape of terrain is approximated by at least
a single or several planes of reflection when calculating the ground effect.

6
The use of reflection planes is required with strict application of Nordic
Prediction Method (NPM).
The intention with this approach is to model the direct path and the reflected
path (as reflected by the ground) separately. Furthermore, NPM states that:
„If more than one valid plane of reflection can be found, the one giving the
highest noise level shall be selected.“
The principle of the procedure to construct the plane/s of reflection as
simple terrain slope is studied (see figure below).
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Calc planes of
reflection
174
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6
Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
Constructing the reflection plane in Nordic Prediction Method (NPM)
The black line represents the terrain slope between source and receiver. In
this simple scenario, two reflection planes can be constructed (each with
different source and receiver heights referring to the respective reflection
plane). According to the above rule the reflection plane giving the highest
level for each receiver point is relevant.
In conjunction with grid calculations the effect of this rule becomes obvious:
At some grid point the relevant reflection plane switches from one to another
causing a level jump on the grid (see figures below).
Vertical grid: road on plane ground, reflecting ground (G=0), highest level occurs from
reflection plane 2 (see before) for the entire grid, no ground effect to the right of the road as
highest level occurs from plane 2 assuming even ground
Vertical grid: road on slope, reflecting ground (G=0), considering reflection plane 1 (see above)
causing ground effect to the right and level jumps to the left of the road
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Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
According to Nordic Prediction Model, section 2.4.1.4, the vertical deviation
from the real terrain shall not exceed +/- 1 m. In addition, it is stated: „+/0.5 m desirable for „hard“ ground“.
6 175
Maximum Deviation (m)
In CadnaA, the default value is 1 meter. The smaller this value the more reflection planes are to be generated, increasing also the calculation time.
By activating this option the screening model is extended by the „Correction
for Thick Screens“ DeltaLts according to part 2, section 2.6.4.
Use Correction for Thick
Screen DeltaLts
This hint refers to the following settings on the „Industry“ tab:
Other Properties: See
Industry
•
•
•
option „lateral diffraction“
option „if distance smaller“
temperature/relative humidity
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Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
Further Information
Ground Absorption
In NPM, the ground can either be acoustically „soft“ or „hard“. There are no
specifications for intermediate ground properties.
In CadnaA, the ground factor G is used to distinguish both cases (see chapter 6.2.7 "Ground Absorption Tab"):
•
soft ground: G > 0.5 (enter G=1)
•
hard ground: G <= 0.5 (enter G=0)
According to NPM, the valid ground type for the situation is the ground type
(absorption factor G) in the area of the reflection point +/- 10 m. In
CadnaA, it depends on the ground absorption factor between the source line
and the reflection point (resp. line) whether soft or hard ground is
considered.
6
Option „Roads/Parking
Lots are reflecting
(G==0)“
Since NPM does account for mixed ground, the option „Roads/Parking Lots
are reflecting (G==0)“ on the „Ground Absorption“ tab (see chapter 6.2.7)
should be deactivated. Otherwise, in case of default G==1 and this option
activated propagation effects will result for receiver or grid points close to or
in direction of the road‘s axis (or of road segments). In this case, these rays
cause a higher level due to reflection by the road surface along their path.
This will lead to unsteady noise contours and level jumps.
Default G==1 and option „Roads/Parking Lots are reflecting (G==0)“ activated:
levels increase or level jumps for receivers/grid points in direction of the road‘s axis
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Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
The distance correction in NPM consists of two parts:
•
the „average distance correction“ DeltaLav according to equation 2.34
and
•
the correction for „short distance to the road“ DeltaLka according to
equation 2.54 (both in /73/).

DeltaLka is a function of the (perpendicular) distance a and the road
width 2b (see chapter 2.5.7 of /73/). This means that the result depends
on the road width entered in CadnaA, even when there is just a single
emission line.
Distance Correction
6
In CadnaA, both corrections are only applied when the option „Calc outer
Lanes separately“ is deactivated (i.e. „strictly NPM“). With the option
activated the distance correction is just based on DeltaLav. In both cases, the
relevant distance is the perpendicular (!) distance to the road‘s axis and not
the distance from the (partial) source to the receiver.
As NPM is basically a „long infinite road“ model it requires an angle
correction to correct for the finite length of a road section. This angle
correction DeltaLalpha (see equation 2.51 /73/) disappears for receiver
locations in direction of the road (with =0°).

Correction for Angle of
View
The angle correction does not apply when calculating maximum levels
(see /73/, chapter 2.6.3).
Provided the option „Calc outer Lanes separately“ is deactivated, both, the
two parts stated in NPM for the overall distance correction, may - in
conjunction with the angle correction - lead to unexpected level jumps and
weird grid contours close to the source. This is immanent to the NPM model
and not a CadnaA specific effect.
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6
Combined Assessment
Road/Railway
Chapter 6 - Calculation
6.2.10.2 Nordic Prediction Method (1996)
In case of assessments with combined impact by road and railway noise the
maximum level of both has to be evaluated according to local legal
provisions. In CadnaA, this can be handled within the configuration, „Evaluation Parameters“ tab (see chapter 6.2.5), by using the expression „max(strd,
schd)“ for the evaluation type „f(x)“:
6
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996
6.2.10.3
NMPB-Routes 1996
6
Dialog Configuration, tab „Road“ for NMPB-Routes 1996
By default, this option is deactivated. In this case, the maximum order of reflection is specified via the „Reflection“ tab (see chapter 6.2.8 "Reflection
Tab").
Calc exactly one
Reflection Order
With this option being activated just 1st order of reflection will be
considered. In this case, higher reflections should be accounted for by the
multiple reflection correction according to RLS-90 /17/ (see below).
When this option is activated the multiple reflection correction is calculated
according to RLS-90 (see chapter 2.4.2 "RLS-90"), based on additional input
data for each road object. By default, this option is deactivated.

The application of both options, „Calc exactly one Reflection Order“
and „Use Multiple Reflection Correction“, may heavily reduce the calculation time as NMPB-method usually requires a higher order of
reflection to be selected to obtain realistic levels.
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Reflection Correction
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996
6
Extended dialog Road to consider the Correction
for Multiple Reflections acc. to RLS-90 (inside red frame)
In this case the dialog is extended at the bottom right by an input scheme to
enter the required data (for details see chapter 2.4.2 "RLS-90", section "Correction for Multiple Reflections").
Calculate outer Lanes
separately
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.5 m). When this option is deactivated just the road’s
center line represents the emission line.
Emission Calculation
Three different types of emission spectrum can be selected:
•
NMPB - Guide de Bruit:
This setting applies the emission spectrum as specified by the original
guideline /77/ (see chapter 2.4.4).
•
Mithra:
This setting applies the modified emission spectrum as used in the former
French software MITHRA which differs from the guideline.
•
EC-guideline 2003/613/EC:
This setting applies the modified emission spectrum (see below) to be
used in conjunction with the EC-interim calculation methods /114/.
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996
The values R(j) of the weighting spectrum to be used in accordance with
2003/613/EC is:
i
Frequency
(Hz)
R(j) in
dB(A)
1
125
-14,5
2
250
-10,2
3
500
-7,2
4
1000
-3,9
5
2000
-6,4
6
4000
-11,4
Reference Spectrum
accord. to 2003/613/EC
6
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
Meteorology
For calculations using NMPB 1996 the following items from the list box apply:
List Box / Locations
•
•
•
•
(default): favorable conditions D/E/N = 50/75/100 %
(favorable): favorable conditions D/E/N = 100/100/100 %
(homogène): favorable conditions D/E/N = 0/0/0 %
XXX (1996) with „XXX“ representing a French town and region: data
for the percentage of favorable conditions according to NMPB 1996.
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996

The items XXX (2) and XXX (3) do not apply when using NMPB 1996,
but refer to NMPB 2008 instead (see chapter 6.2.10.4).

No hint is possible here what percentage may apply to an unknown
location when just a general description of the local orography is
available.
Note 1 - „Favorable conditions“ are such facilitating the propagation of sound (i.e. which are
likely to cause a higher sound pressure level at the receiver point). This situation makes use of the
(spectral) ground attenuation for downwind propagation conditions as specified in ISO 9613-2 /
8/.
Note 2 - The „homogeneous condition“ does not refer to any specific meteorological situation.
In fact, the rays are straight lines, not accounting for any atmospheric influence. This kind of
meteorological situation has been applied by all former prediction models used in France.
6
Evening Values = Day
Values
With this option active the daytime values will be applied for the Evening period as well.
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996
Additional
Information
NMPB applies a different correction with one screen and with two screens.
The correction of ground attenuation for rays above barriers depends on the
distance from the source to the first barrier, and from the distance from the
last barrier to the receiver. Thus, the obtained results are specific to the
NMPB-approach and not due to CadnaA-implementation (see equation (16)
in chapter 7.4.4 of NMPB /77/).
Diffraction Model
The additional road surfaces selectable according to EC-guideline 2003/613/
EC are selectable from the Road dialog, list box “Road Surface“.
Additional Road Surfaces
see chapter 2.4.4 "NMPB-Routes 1996"
The table provides information on combinations of wind speed Ui and temperature Ti corresponding to specific propagation types. The original data is
from LRPC of Angers (Laboratoire Régional des Ponts et Chaussées,
Angers/France) /78/.
In this table, 5 propagation types have been defined:
--
very high attenuation due to very rising rays (“Unfavourable” situation)
-
high attenuation due to rising rays (“Unfavourable” situation)
Z
null meteorological effects due to linear rays (“Homogeneous” situation)
+
moderated increase of noise level due to going down rays (“Favourable” situation)
++
high increase of noise level due to going down rays (“Favourable” situation)
Impossible meteorological situations are marked by grey cells.
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Meteorological
Situations
6
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Chapter 6 - Calculation
6.2.10.3 NMPB-Routes 1996
The input conditions (Ui; Ti) of the grid fit to the following criteria:
6
U1
strong wind (3 to 5 m/s) contrary to the emitter – receptor sense
U2
from light to mean adverse wind (1 to 3 m/s)
U3
no wind or traverse wind
U4
from light to mean carried wind
U5
strong carried wind
and
T1
day; strong radiation; dry surface; not much wind
T2
conditions identical to T1 but one at least is not verified
T3
rising or setting down of sun or (windy and cloudy weather; surface not so wet)
T4
night and (cloudy or windy)
T5
night and clear sky and light wind
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Chapter 6 - Calculation
6.2.10.4 NMPB-Routes 2008
6.2.10.4
NMPB-Routes 2008
6
Dialog Configuration, tab „Road“ for NMPB-Routes 2008
CadnaA displays the edition on which the contemporary implementation is
based upon.
By default, this option is deactivated. In this case, the maximum order of reflection is specified via the „Reflection“ tab (see chapter 6.2.8 "Reflection
Tab").
With this option being activated just 1st order of reflection will be
considered. In this case, higher reflections should be accounted for by the
multiple reflection correction according to RLS-90 /17/ (see below).
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Calculation accord. to
...
Calc exactly one
Reflection Order
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Use Multiple
Reflection Correction
Chapter 6 - Calculation
6.2.10.4 NMPB-Routes 2008
When this option is activated the multiple reflection correction is calculated
according to RLS-90 (see chapter 2.4.2 "RLS-90"), based on additional input
data in the edit dialog of each road object. By default, this option is
deactivated.

6
The application of both options, „Calc exactly one Reflection Order“
and „Use Multiple Reflection Correction“, may heavily reduce the
calculation time as NMPB-method usually requires a higher order of
reflection to be selected to obtain realistic levels.
In this case the dialog is extended at the bottom right by an input scheme to
enter the required data (for details see chapter 2.4.2 "RLS-90", section "Correction for Multiple Reflections").
Calculate outer Lanes
separately
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.05 m). When this option is deactivated just the road’s
center line represents the emission line.
Year of Calculation
Enter here the actual year of calculation used to correct for the aging of the
road surface (for details see chapter 2.4.5 "NMPB-Routes 2008").
Meteorology
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
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Chapter 6 - Calculation
6.2.10.4 NMPB-Routes 2008
For calculations using NMPB 2008 the following items from the list box apply:
•
•
•
•
(default): favorable conditions D/E/N = 50/75/100%
(favorable): favorable conditions D/E/N = 100/100/100%
(homogène): favorable conditions D/E/N = 0/0/0%
XXX (2) and XXX (3) with „XXX“ representing a French town and
region: data of the percentage of favorable conditions for two (2: D, N) or
three time periods (3: D, E, N) according to NMPB 2008.

The items XXX (1996) do not apply when using NMPB 2008, but refer
to NMPB 1996 instead (see chapter 6.2.10.3).

NMPB 2008 specifies the following hours for the respective periods:
List Box / Locations
6
 2 periods: D 6-22 h, N 22-6 h
 3 periods; D 6-18 h, E 18-22 h, N 22-6 h
When assessing mixed levels (e.g. Lden or Ldn) the respective reference
times have still to be defined on tab „Reference Time“ (see chapter
6.2.4). CadnaA does not set those periods automatically based on the
type of meteorology item selected from the list box.

No hint is possible what percentage may apply to an unknown location
when just a general description of the local orography is available.
Note 1 - „Favorable conditions“ are such facilitating the propagation of sound (i.e. which are
likely to cause a higher sound pressure level at the receiver point). This situation makes use of the
(spectral) ground attenuation for downwind propagation conditions as specified in ISO 9613-2 /
8/.
Note 2 - The „homogeneous condition“ does not refer to any specific meteorological situation.
In fact, the rays are straight lines, not accounting for any atmospheric influence. This kind of
meteorological situation has been applied by all former prediction models used in France.
With this option active the daytime values will be applied for the Evening
period as well.
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Values
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6
Calc Atalus
Chapter 6 - Calculation
6.2.10.4 NMPB-Routes 2008
In NMPB 2008, the attenuation due to the embankment Atalus is part of the
attenuation due to the boundary of the propagation medium in downward
refraction conditions Afront,F („talus“ is French for „embankment“).
This option is activated by default. In this case, Atalus is calculated and
included in Afront,F. When deactivated, Atalus is zero.

6
This option is also relevant when applying the „reference DLL“ (see
below).
Use Ch in Calculation
of Abar
By the factor Ch the attenuation by „pure diffraction“ is modified for barriers
(not for terrain contours). Activating this option may lead to a lower barrier
attenuation (for details see /80/).
Use reference DLL
This option is deactivated by default. In this case, CadnaA code is used for
the calculation, implemented based on the printed documentation of NMPB
2008.
By activating this option the later released, but officially provided reference
DLL (developed by the French consortium) is used for the calculation.
This option requires to copy the reference DLL (PropagationNMPB.dll) into
the respective CadnaA installation directory. The DLL is not part of the
CadnaA installation procedure and is, therefore, distributed separately.
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Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
6.2.10.5
CNOSSOS-EU
6
By default, this option is deactivated. In this case, the maximum order of
reflection is specified via the „Reflection“ tab (see chapter 6.2.8 "Reflection
Tab").
Calc exactly one
Reflection Order
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.05 m). When this option is deactivated just the road’s
center line represents the emission line.
Calculate outer Lanes
separately
By deactivating this option the reference conditions are used (temperature 15
°C, relative humidity 70%). When activated the settings for temperature and
relative humidity on the „Industry“ tab apply (see chapter 6.2.9.9).
Use Temperature
from Industry-Tab

Air absorption in CNOSSOS-EU is calculated according to ISO 9613-1
/8/.
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Studded Tyres, Period
Ts (months)
6
Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
Number of months where studded tyres are used (within a single year).

In CNOSSOS-EU, the increase in rolling noise emission due to studded
tyres is only attributed to the proportion of light vehicles (i.e. class 1, see
below).
Studded Tyres, Percentage Qstud,ratio
(%)
This is the average ratio of the total volume of light motor vehicles per hour
equipped with studded tyres during the period Ts (in months).
Max. Speeds of Vehicle Classes
Specification of the maximum speeds for each vehicle class:
Class
Name
Description
1
Light motor vehicles
Passenger cars, delivery vans <= 3.5 tons, SUVs,
MPVs including trailers and caravans
2
Medium heavy vehicles
Medium heavy vehicles, delivery vans > 3.5 tons,
buses, motorhomes, etc. with two axles and twin tyre
mounting on rear axle
3
Heavy vehicles
Heavy duty vehicles, touring cars, buses, with three
or more axles
4a
Powered two-wheelers
Two-, Three- and Four-wheel Mopeds
4b

Motorcycles with and without sidecars, Tricycles and
Quadricycles
In CNOSSOS-EU there are two types of maximum speeds: the
maximum legal speed of the vehicle category and the maximum legal
speed of the road or a road section (see chapter 2.4.6). In the
calculation, the lower of both applies.
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Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
These default percentage values apply when the road‘s emission is specified
as MDTD (with or without use of diurnal patterns), and not by hourly traffic
data. In this case, default percentage values for the amount of vehicles of
class 3 in the sum of (2+3), and amount of vehicles of class 4b in the sum of
(4a+4b) are required.
Default Percentages
Default values: (2+3)=50, (4a+4b) =50.
This button enables to modify the emission parameters for the five
CNOSSOS-EU specific vehicle classes.
Vehicle Classes
6
With this setting, the parameters specified in CNOSSOS-EU /16/ are used.

Default
When toggling from option „User-defined“ back to „Default“, the
edited values in the table - if any - remain unchanged. Nevertheless, the
default values are used in the calculation.
This setting enables to edit the following parameters in octave bandwidth:
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Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
Parameter
6
Description
Ar
coefficient Ar for rolling noise
Br
coefficient Br for rolling noise
Ap
coefficient Ap for propulsion noise
Bp
coefficient Bp for propulsion noise
Astudded
correction coefficient a for studded tyres (for class 1)
Bstudded
correction coefficient b for studded tyres (for class 1)
Cr,signal
coefficient for rolling noise at crossings with traffic lights
Cr,roundabout
coefficient for rolling noise at roundabouts
Cp,signal
coefficient for propulsion noise at crossings with traffic lights
Cp,roundabout
coefficient for propulsion noise at roundabouts
Ktemperature
temperature correction Km
Note - The coefficients Cr,signal, Cr,roundabout, Cp,signal and Cp,roundabout are non-spectral
in CNOSSOS-EU, but are shown here as a spectrum.
In case several user-defined parameter sets are required, each set can be saved
and loaded in conjunction with the configuration of calculation (see chapter
6.2.1 "Country Tab").
Copy & Paste buttons
These buttons can be used to copy or paste the selected dataset for a vehicle
category (including the row and column identifiers) to or from the clipboard.
Note that the „Paste“ button will just highlight in case the data stored in the
clipboard has the required format. Therefore, copy the existing data using the
„Copy“ button, then modify it as required in an external software and copy
the entire table back the clipboard.
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Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
Meteorology
6
For further details on this dialog, see chapter 6.2.10.4, section "Meteorology".
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Chapter 6 - Calculation
6.2.10.5 CNOSSOS-EU
6
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Chapter 6 - Calculation
6.2.10.6 CRTN
6.2.10.6
CRTN
6
Dialog Configuration, tab „Road“ for CRTN
Select the evaluation parameter from the list box:
•
•
L10: This option evaluates the L10 level according to CRTN (default setting).
Leq acc. to Annex A Method 1 of TRL study: The conversion rules
according to method 1 of TRL study are applied (using equations (4.4)
and (4.5) of /83/). The conversion is based on the same segmentation
rules as being used for L10 calculations.
Since the conversion for non-motorways with hourly traffic flows < 200
veh/h and during the period 24:00 to 06:00 hours deviates (see equation
(4.5) of /83/) note the following points:
 A further check-box „Motorway“ is displayed on the dialog Road (see
chapter 2.4.7) enabling to distinguish between motorways and nonmotorways.
 Allocate the period 24:00 to 06:00 hours to the nighttime by typing in
6 letters N (see chapter 6.2.4 "Reference Time Tab"). Note that just
the hourly traffic from 24:00 to 06:00 hours having N's is taken (when
using diurnal patterns).
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6
Use Non Standard
Reference Time
D/E/N = 12/4/8
6
Chapter 6 - Calculation
6.2.10.6 CRTN
•
Leq = L10 - 3.0 dB: This approach to evaluate Leq from L10 is used in
Australia.

In order to apply Annex A Method 3 of TRL study /83/ to noise grids
and receivers see chapters 5.3.4 and 11.2.1.
When using diurnal patterns the hourly traffic flow considered to calculate
the emission is by default restricted to the time interval from 6:00 to 24:00
hours. To apply the daily hours as allocated to the intervals D/E/N on the
„Reference Time“ tab this option has to be activated.

Example
The application of diurnal patterns with this option deactivated (i.e.
strictly applying CRTN) is explained in chapter 2.4.7.
In this example, the daily intervals D/E/N are set to D from 4 to 18 hours
(14 hours), to E from 18 to 22 hours (=4 hours), and to N from 22 to 4 hours
(= 6 hours).
Dialog Calculation|Configuration, „Reference Time“ tab
The following diurnal pattern „patt_01“ is used in this example. Traffic
figures are 200 vehicles/h from 0:00 to 6:00 hours, and 1000 vehicles/h from
6:00 to 24:00 hours (with HGV=20% for each hour).
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Chapter 6 - Calculation
6.2.10.6 CRTN
6 197
6
Diurnal Pattern „patt_01“
The hourly traffic data for periods D/E/N result from (see dialogs below):
for D: 12400 veh/14 h = 885.71 veh/h
for E: 4000 veh/4 h = 1000 veh/h
for N: 2800 veh/6 h = 466.67 veh/h
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Chapter 6 - Calculation
6.2.10.6 CRTN
The figure to be entered to normalize to a different total traffic count Q still
refers to the traffic counts within the time interval from 6:00 to 24:00 hours
(i.e. 18 hours) of the pattern selected.
Example 1:
diurnal pattern PATT_01 with
Q=0 veh/18 h (6-24h)
applies full traffic counts as from
selected diurnal pattern
6
Example 2:
diurnal pattern PATT_01 with
Q=9000 veh/18 h (6-24h)
applies - in this example - 50%
of the traffic counts from the
selected diurnal pattern
(so, not entering 50% of 19200
veh/24h = 9600 veh/24h
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Chapter 6 - Calculation
6.2.10.6 CRTN
Clause 30 of CRTN specifies that for a road segment where the traffic flow is
in the range 50<=q<200 veh/h or 1000<=Q<4000 veh/18h and the
shortest slant distance d' source-receiver is less than 30 metres a low trafficcorrection shall be applied. The low traffic-correction K is calculated
according to chart 12 of CRTN.
Use Low TrafficCorrection K
In CadnaA, the conditions for q (attributes MT, ME, MN) or Q (attribute
DTV) are checked depending on what is selected. The low traffic-correction
is applied to all receivers or grid points meeting the conditions.

The emission value L10 displayed on the dialog Road, however, does
not include the low traffic-correction as the receiver's distance is not
available for a road object.
In CadnaA, for traffic flows lower than the lower limit the following is
applied:
•
q<50 veh/h: K=K(q=50 veh/h)
•
Q<1000 veh/18h: K=K(1000 veh/18h)

The restriction in CRTN, clause 30, that „otherwise no correction
should be applied“ is, therefore, not respected for values q or Q smaller
than the respective lower limit. On the other hand, this strategy avoids,
for example, the emission level to increase for q=49 veh/h compared
with q=50 veh/h when not applying such a strategy.
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200
6
Reflection via
Correction (1.5 dB),
NOT via mirror
sources
6
Chapter 6 - Calculation
6.2.10.6 CRTN
CRTN clause 26.2 specifies that the reflection from buildings or other
reflecting objects (e.g. barriers) on the opposite side of the road have to be
considered by a correction of 1.5 dB depending on the angle of the reflecting
object/s seen from the receiver. The value of 1.5 dB occurs in case the entire
length of the road has reflecting buildings (i.e. is the maximum reflection correction).
When activating this option this CRTN-specific reflection correction of +1.5
dB is applied. CadnaA considers the sum of angles of reflection in relation to
the total segment angle as specified in figure 5 of CRTN.
long road with opposite
reflecting barrier,
reflecting barrier deactivated
reflecting barrier activated,
calculation of reflections
according to CRTN clause 26.2
Note - Level increase is just 1.4 dB due to
finite road & barrier length.
With this option being deactivated, the increase due to reflections is
calculated by mirror sources (as usually with CadnaA). In this case, the settings on „Reflection“ tab apply (e.g. order of reflection etc.).

Buildings/barriers should be set to reflective for reflections to be
included.
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Chapter 6 - Calculation
6.2.10.6 CRTN
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6
Reflected rays by a barrier (1st order of reflection)
However, the results with this option deactivated are not in line with the
specifications of CRTN.

Buildings and barriers with an absorption coefficient of less than 0.8
will be accounted for as being reflecting in CRTN calculations where
the max. 1.5 dB correction applies. Buildings and barriers with an
absorption coefficient larger or equal to 0.8 will be excluded from the
1.5 dB-correction.
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6
Calc accord. to
"Design Manual for
Roads and Bridges
(DMRB)"
6
Chapter 6 - Calculation
6.2.10.6 CRTN
The "Design Manual for Roads and Bridges" (release August 2008 /85/)
states the following modifications to CRTN-calculation:
•
road surface correction editable (attribute DSTRO),
•
no further increase of ground absorption beyond 600 m distance from
the road (Agr=Agr(600 m) for d>600 m),
•
additional rules whether reflections from opposite facades or barriers
occur.
With this option activated the DMRB-calculation rules are applied.

The option "Reflection via Correction (1.5 dB), NOT via mirror
sources" needs to be activated in this case.
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Chapter 6 - Calculation
6.2.10.6 CRTN
Additional
Information
CRTN specifies in clause 26.1 that for calculations of the noise level at a distance of 1 metre in front of a façade a correction of +2.5 dB has to be made.
CadnaA does not apply this correction automatically for the time being as
this CRTN-specification does not match the normal approach when calculating façade reflections.
By default, the façade level at receiver points in front of the façade (e.g. at
0.05 m off the facades plane) does not include reflections at the own
buildings surface. This is achieved in CadnaA by setting the "Minimum Distance Receiver-Reflector" to e.g. 1 m (so, larger than the distance of the receiver from the façade).
Reflections are calculated when this distance is set to 0 m, when the building
is reflective, and when at least the first reflection order has been selected
(Configuration dialog, „Reflection“ tab). To apply the correction of 2.5 dB
for CRTN-calculation the following conditions have to be fulfilled:
•
The option "Reflection via Correction …" on the „Road“ tab of the
dialog Configuration is activated.
•
Each receiver intended to consider the CRTN-correction of +2.5 dB has
the text-variable FACADE=1 specified on the receivers memo window.
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Facade Effect
6
204
6
Chapter 6 - Calculation
6.2.10.6 CRTN
6
The building below has got two receivers attached to its facade.
Two receivers at building’s facade, left rcvr with correction, right rcvr w/o
The receiver on the left has a string variable FACADE=1 defined. The
increase of 2.5 dB according to CRTN is considered. The receiver on the
right has no text variable defined (or with the text variable being zero,
FACADE=0). Thus, the level increase is not added.
Grid calculations for EUnoise indices
see chapter 5.3.4 "Grid Arithmetic", section "Grid calculations for EU-noise
indices with CRTN"
Conversion to EU-indices
at individual receivers
see chapter 11.2.1 "Editing the Result Table", section "Conversion to EUindices at individual receivers with CRTN / TRL"
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Chapter 6 - Calculation
6.2.10.7 TNM
6.2.10.7
6 205
TNM
6
Dialog Configuration, tab „Road“ for TNM
By default, all available settings listed below are deactivated.
The emission model of TNM considers - depending on the type of source several emission heights. Activating this option will level down all types of
sub-sources to a common height of 0.1 m above road surface.
option deactivated:
up to 3 sub-sources visible on the
vertical grid (at 0.1/1.5/3.66 m)
CadnaA - Reference Manual
option activated:
just a single source height at 0.1 m
(for both: Adiv based on 3D-distance)
All Emissions at 0.1
m above road surface
206
6
Use 3D-distance for
calculation of Adiv
Chapter 6 - Calculation
6.2.10.7 TNM
In TNM, the geometrical divergence is calculated based on the 2D-path
length in xy-plane only. This causes the receiver level not depending on
height (i.e. level is not decreasing with receiver height). By activating this option calculated levels will depend on receiver height or height of grid points.
6
option „3D-distance for calculation of
Adiv“ deactivated
(i.e „strictly accord. to TNM“)
Correct bug in
Fresnel-zonecalculation
option „3D-distance for calculation of
Adiv“ activated
In TNM 2.5-code a sign error in the calculation of Fresnel zones was
discovered altering calculation results reasonably. With this option activated
the Fresnel-zone-bug will be corrected for in CadnaA-TNM.

In case results shall be compared with results obtained by TNM 2.5
software this option should, however, be deactivated.
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Chapter 6 - Calculation
6.2.10.7 TNM
In order to obtain correct results in comparison with the release 2.5 of the
TNM software further configuration settings are to be respected. Those are
described below.
Additional
Information
Regarding the ground attenuation, the settings (on Calculation|
Configuration menu, tab "Ground Absorption") are based on the ground
absorption factor G of ISO 9613-2 /8/. For the time being, the following
airflow resistivities refer to the ground absorption factor G:
Ground Absorption
Airflow Resistivity
(in rayls)
Ground Absorption
Factor G (ISO 9613-2)
TNM-specific ground
type
20000
0 (i.e. reflecting)
pavement
1000
0.33
*)
600
0.5
*)
400
0.67
*)
300
1 (i.e. absorbing)
lawn
6
*) These ground types are not available in CadnaA for the time being.
In addition activate the option „Roads/Parking Lots are reflecting (G==0)“.

The latter setting will - in conjunction with the additional width from
self-screening (see below) - ensure that the entire road width as
considered by TNM is reflecting (and not just the region between the
emission lines).
Activate on the Calculation|Configuration option „Explicit Edges only“,
„DTM“ tab (see chapter 6.2.6 "DTM Digital Terrain Model Tab").

TNM 2.5 software just triangulates between „real“ terrain contours, not
using the heights of objects (e.g. roads and barriers with absolute
heights). For this reason it is required that the geometry of all objects is
imported additionally as terrain contours or heights points, as otherwise
they will not influence the resulting terrain shape.
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DTM: Explicit Edges only
208
6
Self-Screening of Roads
Chapter 6 - Calculation
6.2.10.7 TNM
Activate for all types of roads the option "Self-Screening" (dialog Road|
Geometry) and enter an additional width of 1.83 m (6 feet).
6
Dialog Road:Geometry: self-screening
with additional width left/right of 1.83 m

Temperature and relative
Humidity
The general settings for the temperature and the relative humidity in CadnaA
match with the default settings in TNM 2.5-software (see menu
Calculation|Configuration, tab "Industry"):
•
•
Restrictions
Changing the attribute’s values for all roads in a project is achieved
conveniently via the dialog Modify Objects|Modify Attribute, for
attributes SCCR_AW_L and SCCR_AW_R, respectively.
50% relative humidity
temperature 20°C
The following features of the TNM-software are not implemented in
CadnaA for the time being:
•
•
•
no TNM-specific parallel barrier analysis,
no accelerating ramps and flow control devices, and
no import of TNM-files.
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Chapter 6 - Calculation
6.2.10.8 Czech Method
6.2.10.8
6 209
Czech Method
6
Dialog Configuration, tab „Road“ for Czech Method (accord. to Liberko)
The available configuration settings comply with those for RLS-90 (see chapter 6.2.10.1 "RLS-90").
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Chapter 6 - Calculation
6.2.10.8 Czech Method
6
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6 211
Chapter 6 - Calculation
6.2.10.9 SonRoad
6.2.10.9
SonRoad
6
Dialog Configuration, tab „Road“ for SonRoad
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.5 m). When this option is deactivated just the road’s
center line represents the emission line.
Calculate outer Lanes
separately
see chapter 6.2.10.3 "NMPB-Routes 1996", section "Meteorology"
Meteorology
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Chapter 6 - Calculation
6.2.10.9 SonRoad
6
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Chapter 6 - Calculation
6.2.10.10 HJ 2.4 (2009)
6 213
6.2.10.10 HJ 2.4 (2009)
6
Dialog Configuration, tab „Road“ for HJ 2.4 (2009)
By default, the center lines of the outermost lanes of a road are the emission
lines (at a height of 0.5 m). When this option is deactivated just the road’s
center line represents the emission line.
CadnaA - Reference Manual
Calculate outer Lanes
separately
214
6
Chapter 6 - Calculation
6.2.10.10 HJ 2.4 (2009)
6
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Chapter 6 - Calculation
6.2.11 Railroad Tab
6.2.11
6 215
Railroad Tab
Information on the calculation options for the following standards or
guidelines for industry can be found in the German version of the CadnaA
reference manual:
 ONR 305011 (Austria)
 DIN 18005 (1987, Germany)
 Semibel (Switzerland)
The subsequent table lists the main characteristics of the propagation models
for railroad noise as treated in the chapters explaining the configuration
options. A special focus is put to the type of modeling being used for the
various attenuating effects in sound propagation.
Table „Propagation
Models Railroad“
A further table describes the properties of obstacles and special-objects in
CadnaA with each propagation model.
Table „Obstacles and
Special-Objects“
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216
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Chapter 6 - Calculation
6.2.11 Railroad Tab
Propagation Models Railroad
6
No
Option or
Propagation
Effect
Standard / Guideline
1
calculation using
A-weighted levels
yes
yes
yes
2
spectral
calculation
no
yes
yes
3
geometrical
attenuation
(divergence)
half sphere (2 r2) with directivity
full sphere (4 r2) with directivity
full sphere (4 r2)
4
attenuation by
air absorption
yes (according to VDI 2714)
using air absorption accord.
to ISO 9613-1
yes (for 15°C, 70% RH)
5
handling of ground
reflections
not by image sources, but by an algorithm considering ground
attenuation and meteorological effects in common (see below)
as above
algorithmic, not by image
sources
6
handling of
reflections
at obstacles
just up to 1st order, higher orders applying a „Correction for
multiple Reflections“, optionally: calculation to up 20th order,
condition for reflection considers obstacle’s size and absorption
coefficient/reflection loss of the reflector
as above, by default up to
3rd order (accord. to Sch03
2014) or up to 20th order
see Schall 03 (1990)
7
attenuation due to
ground effect
(ground
attenuation)
for A-weighted levels (not applying ground factor G)
alternative procedure (for Aweighted levels) accord. to
ISO 9613-2, deviating calculation procedure for water
surfaces
complies with spectral
ground attenuation model of
ISO 9613-2
8
attenuation due
to screening
(at objects)
single and double diffraction based on the path length difference
of the direct path via the obstacle, screening effect does not
depend on wavelength (as just for A-weighted levels), negative
path difference cause no screening
REMARK: „acoustical Transparency“ of buildings not available
single & double diffraction
using path difference, ray
across obstacle w/o ground
absorp., barrier attenuation
depending on wavelength
concept of effective height
9
handling of
lateral diffraction
not considered, in CadnaA optionally available
with lateral diffr. (using two
lat. paths + direct path)
not considered
10
handling of
multiple obstacles
in ray path
based on the path length difference of the direct path across all
obstacles („ribbon band method“)
in CadnaA: applies „rubber
band method“ to calculate
path difference
using the most efficient
screen
11
attenuation due
to screening
(terrain)
screening by terrain not treated explicitly,
In CadnaA the algorithm for multiple screening objects is
applied.
as above
as with multiple screens
12
handling of
meteorological
effects (wind)
not treated explicitly (meteorological correction is part of the
screening calculation), optional: application of Cmet accord. to
ISO 9613-2, with calculations acc. to VBUSch: applies Cmet
with C0,D/E/N=2/1/0 dB
no
not available
13
attenuation due to
foliage
without screening calculation, but based on the length of the
curved ray path (arc of a circle) passing through the foliage (with
height h) assuming a radius of 5 km
not available
available
14
attenuation due to
built-up areas
not considered, in CadnaA optionally accord. to VDI 2714
not available
available
Schall 03 (1990)
Schall 03 (2014)
Nordic (1996)
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6 217
Chapter 6 - Calculation
6.2.11 Railroad Tab
Standard / Guideline
CRN
SRM II
NMPB-Fer (1996)
NMPB-Fer (2008)
No
FTA/FRA
CNOSSOS-EU
yes
yes
see chapter 6.2.10,
for NMPB96
yes
yes
yes
1
no
yes
(63 to 8000 Hz)
as above
yes (1/3 octaves, 100
to 5000 Hz)
no
yes (octaves 63 Hz
to 8 kHz, + 31.5 Hz
2
in CadnaA: segmented
line source
segmented line
source (distance &
viewing angle)
as above
point source propagation (4r2)
in CadnaA: segmented line source
point source propagation (4r2)
3
not considered
yes (10°C, 80%),
option: ISO 9613-2
as above
acc. ISO 9613-1 (for
15°C, 70%)
not considered
yes (acc. to ISO
9613-1)
4
algorithmic, not by
image sources
algorithmic, not by
image sources
as above
algorithmic, not by
image sources
algorithmic, not by
image sources
algorithmic incl.
ground absorp.
5
using a global correction, optional in
CadnaA: using
image sources
using image sources,
absorption coeff./
reflection loss of
reflector
as above
no mult. reflect. correction by default,
optional in CadnaA
using image sources,
absorption coeff./
reflection loss of
reflector
yes
6
empirical
correction
spectral ground
attenuation model
applying ground factor G (similar to ISO
9613-2)
as above
spectral model (for
favorable: ISO 96132, for homogeneous
specific)
using ground factor
G, in CadnaA: average height (acc. ISO
9613-2)
homogeneous &
favorable conditions
using ground factor
G
7
based on path length
difference, negative
path difference
causes screening
concept of effective
height
as above
based on path length
difference
based on path length
difference and
source height
single & double
diffr., includes
ground effect, using
image source
method
8
not considered
not considered
as above
not expressively
considered
not considered
yes, at 2 vert. edges
(incl. ground abs.)
9
based on path length
difference
concept of equivalent screens (instead
of multiple diffraction)
as above
via path length difference
see Schall 03 (1990)
via path length difference (convex hull)
10
as with multiple
screens
as with multiple
screens (no lateral
diffraction)
as above
as with multiple
screens
see Schall 03 (1990)
see ISO 9613-2
11
not available
available using Cm
(upper limit 3.5 dB),
optional: Cmet acc.
to ISO 9613-2
as above
using occurrences of
homogeneous and
favorable propagation conditions
not considered
for homogeneous &
favorable prop.
cond., energetic
addition
12
not available
not available
as above
not available
in CadnaA not
available
not available
13
not available
not available
as above
not available
in CadnaA not
available
not available
14
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6
218
6
Chapter 6 - Calculation
6.2.11 Railroad Tab
Obstacles and Special-Objects
6
No
Object Type/
Option
Standard / Guideline
1
building
single & multiple diffraction using shortest path difference, no lateral diffraction by default, no reflection or
by absorption coefficient/reflection loss, no acoustical
transparency
see Schall 03 (1990)
see Schall 03 (1990)
2
cylinder
single & multiple diffraction using shortest path difference, no lateral diffraction by default, no reflection or
by input of absorption coefficient/reflection loss,
reflection up to 1st order
see Schall 03 (1990)
see Schall 03 (1990)
3
barrier
single & multiple diffraction using shortest path difference, no lateral diffraction by default, no reflection or
by absorption coefficient/reflection loss
see Schall 03 (1990)
see Schall 03 (1990)
4
floating
barrier
no diffraction via the lower edge (screening edge
without diffraction), otherwise see barrier
see Schall 03 (1990)
see Schall 03 (1990)
5
barrier with
cantilever
cantilever is totally absorbing (no reflection), calculation
of the path length difference valid for receivers/grid
points outside and below the cantilever, otherwise see
barrier
see Schall 03 (1990)
not available (due to
„effective height“
concept)
6
bridge plate
diffraction as a horizontal plate only (inclined plate
approximated to horiz. plate), screening occurs for
sources above the bridge plate (diffraction downwards),
no reflection at bridge plate
see Schall 03 (1990)
see Schall 03 (1990)
7
embankment
acts as a double barrier, diffraction for direct path (no
lateral diffraction), no absorptive/reflective properties,
NOTE: The embankment is not considered in the
triangulation!
see Schall 03 (1990)
see Schall 03 (1990)
8
ground
absorption area
not relevant (generalized ground attenuation)
areas with G=0
assumed to represent
water surfaces
yes, freq. dependent
using ground factor
G (as in ISO 9613-2,
section 7.3.1)
9
built-up area/
foliage
not relevant by default, optionally accord. to VDI 2714
optionally accord. to
ISO 9613-2
built-up area by
sound dispersion
(NPM), foliage: via
path length with heff
10
3D-reflector
screening based on shortest path difference, two lateral
paths, no reflection or by absorption coeff./reflection
loss, reflection up to 1st order, no summation of
diffraction via multiple edges, no multiple diffraction
see Schall 03 (1990)
not available (due to
„effective height“
concept)
11
self screening
additional feature in CadnaA: causes screening effect
downwards, additional with left/right available (fixed to
the road, screening just for the own road source)
see Schall 03 (1990)
see Schall 03 (1990)
12
additional width/
parapet L/R
parapet left/right available, parapet length can be
restricted using station marks, additional width just for
ground absorption with no effect with Schall03
see Schall 03 (1990)
see Schall 03 (1990)
Schall 03 (1990)
Schall 03 (2014)
Nordic (1996)
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6 219
Chapter 6 - Calculation
6.2.11 Railroad Tab
Standard / Guideline
CRN
SRM II
No
NMPB-Fer (1996)
NMPB-Fer (2008)
FTA/FRA
CNOSSOS-EU
see Schall 03 (1990)
see Schall 03 (1990)
see NMPB-routes
(1996), chapter
6.2.10
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990),
but for homogeneous & favorable
conditions
1
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
for homogeneous &
favorable conditions
2
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990),
but for homog. &
favorable cond.
3
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990)
4
available, using path
length difference
not available (due to
„effective height“
concept)
as above
not available
not available (just for
vertical barriers)
see Schall 03 (1990)
5
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990)
6
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990)
7
empirical ground
correction (chart)
freq. dependent
using ground factor
G (see ISO 9613-2,
section 7.3.1)
as above
using ground
factor G (for
favorable and homogeneous)
using ground factor
G, averaging with
multiple ground
absorption areas
yes, using ground
factor G (for
favorable and homogeneous)
8
not available
not available
as above
not available
not available in CadnaA (for the time
being)
no effect
9
see Schall 03 (1990)
not available
(due to „effective
height“ concept)
as above
not available
not available (just for
vertical barriers)
not available
10
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990)
11
see Schall 03 (1990)
see Schall 03 (1990)
as above
see Schall 03 (1990)
see Schall 03 (1990)
see Schall 03 (1990)
12
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220
6
Chapter 6 - Calculation
6.2.11 Railroad Tab
6
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Chapter 6 - Calculation
6.2.11.1 Schall 03 (1990)
6.2.11.1
6 221
Schall 03 (1990)
6
Dialog Configuration, tab „Railroad“ for Schall 03 (1990)
(option „strictly according to Schall 03“ deactivated)
With this option activated, CadnaA will calculate for railways
•
•
•
•
•

only the first-order reflections, irrespective of the order of reflection
specified on the „Reflection“ tab,
considering a railway correction of 5 dB,
no lateral diffraction at obstacles,
no attenuation by built-up areas, and
no meteorological correction.
All other settings made on the „Reflection“ tab, "Conditions for
Calculation of Reflection", such as the search radius for reflecting
objects, will apply even when the option „Strictly according to Schall
03/Schall-Transrapid“ is activated (see chapter 6.2.8 "Reflection Tab").
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Strictly according to
Schall 03
222
6
Chapter 6 - Calculation
6.2.11.1 Schall 03 (1990)
Calc exactly one
reflection order
With this option deactivated the maximum order of reflection is specified via
the „Reflection“ tab (see chapter 6.2.8 "Reflection Tab").
No Lateral Diffraction
When this option is deactivated the lateral diffraction will be considered
which is normally not relevant to the receiver level due to the extension of
the railway sources (line sources) in normal situations
No Housing
Attenuation
By default, the attenuation by built-up areas is not considered by Schall 03.
When this option is deactivated the CadnaA-object „Built-Up Area“ causes a
screening effect.
6

Railway Correction
(dB)
The housing attenuation DG is calculated accord. to VDI 2714 (see
chapter 3.5 "Built-Up Areas and Foliage"). This value is not displayed
on the calculation protocol in a separate column (see CadnaA-manual
„Attributes, Variables, and Keywords“, chapter "Chapter 6 - Protocol
Abbreviations").
Any entered railway correction will be considered upon calculation. Thus, to
consider no railway correction a value of 0 dB has to be entered.
see also section "Strictly according to Schall 03"
No Meteorology
(Cmet see Industry)
No meteorological correction is established by Schall 03. In CadnaA,
nevertheless, the meteorological effect can be considered by deactivation of
this option. In this case, the settings on the list box „Meteorology“ on the
„Industry“ tab are relevant.

The value of Cmet will be calculated according to ISO 9613-2. This value
is not displayed on the calculation protocol.
see also: chapter 6.2.9.1 "ISO 9613", section "Meteorology"
CadnaA - Reference Manual
6 223
Chapter 6 - Calculation
6.2.11.1 Schall 03 (1990)
With performing calculations according to END (Environmental Noise
Directive /121/), this option has to be activated. In this case, the number of
trains (or the emission parameter) during the Evening period is considered as
well. The values displayed on the „Reference Time“ tab („D/E/N=12/4/8
h“) will be updated based on the defined time intervals (see chapter 6.2.4 and
chapter 6.2.5 "Evaluation Parameters Tab").
Use Non-Standard
Reference Time D/E/
N
relevant for Germany only!
Calculation acc. to
VBUSch
The German method VBUSch is just relevant in conjunction with
evaluations for END /121/. First, deactivate the option „Strictly according
to Schall 03“ and activate the option „Calculation acc. To VBUSch“.
The main modifications are:
•
•
•
The setting for lateral diffraction is not possible any longer.
No railway bonus specifiable.
Cmet is calculated automatically (C0 (D/E/N)=2/1/0 dB).

When not considering Cmet and with the same emission D/E/N a level
difference between Lden and Ln of 6.395 dB results. Since Cmet is automatically taken into account in CadnaA, the difference is usually
smaller than this value.
•
•
fixed reference Time Day/Evening/Night = 12h/4h/8h
The penalty for railway lines with wooden sleepers is 2 dB (instead 0 dB
according to Schall 03).
For maximum speeds vmax>200 km/h an additional aerodynamic noise
source is included at a source height of 4,5 m.
•
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224
6
Self-Screening at
Buildings
6
Chapter 6 - Calculation
6.2.11.1 Schall 03 (1990)
For calculations according to the German railway guideline Schall 03 the selfscreening of buildings with backside receivers can alternatively be considered
or not. This option refers to a requirement stated by Schall 03 (section 7.5)
that „at buildings with gaps in between ... just the screening by the first row
of buildings, being next to the railway line, shall be considered ...“ (translated
from German).
To do so, a string variable SCREEN_TEST_ID=1 (on the dialog MemoWindow) is defined for the respective building. With the variable being set it
will be checked whether the ID of a receiver corresponds with the building‘s
ID. With corresponding IDs the respective building is screening, otherwise
not.
This option enables to respect the detailed specification of Schall 03, just to
consider the screening by the first row of buildings, while for backside facades the self-screening effect shall be included.
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Chapter 6 - Calculation
6.2.11.2 Schall 03 (2014)
6.2.11.2
Schall 03 (2014)
6
Dialog Configuration, „Railway“ tab for Schall03 (2014)
Options
When enabled, at maximum three orders of reflection are calculated
regardless of the order selected on the „Reflection“ tab (see chapter 6.2.8).
This setting follows strictly the specifications in Schall03 (2014) /26/
(„reflections higher than the 3rd order remain unconsidered...“).
Calc exactly three Orders
of Reflection
When deactivated, the maximum reflection order as set on the „Reflection“
tab set is considered.
When activated, all the emission of all sub-sources are set to a source height
of 0.0 m above railhead (0.6 m above ground).
All Emissions at 0.0m
above railhead
When this option is deactivated the lateral diffraction will be considered
which is normally not relevant to the receiver level due to the extension of
the railway sources (line sources) in normal situations.
No Lateral Diffraction
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Chapter 6 - Calculation
6.2.11.2 Schall 03 (2014)
Ground with G=0.00
represents Water in Eq.
16
When activated all ground absorption areas having a ground factor G=0.00
are considered as water surfaces and their damping Agr,w is calculated
according to equation 16 in /26/.
Use Non-Standard
Reference Time D/E/N
With this option deactivated the following time interval lengths will be
considered: Day (D)=16 hours, Night (N)=8 hours. When this option is
activated, however, the time intervals and penalties on the „Reference Time“
tab (see chapter 6.2.4) are taken into account.
This option has to be activated for calculations according to END
(Environmental Noise Directive /121/) in order to consider the number of
trains (or the emission parameter) during the Evening period as well.
6

The values displayed here are updated based on the defined time
intervals D/E/N on the „Reference Time“ tab.
Railway Correction (dB)
Any entered railway correction will be considered upon calculation. Thus, to
consider no railway correction a value of 0 dB has to be entered.
Determine Raster Factor
iteratively
According to Schall03 (2014) is has to be checked during segmentation of the
railway tracks whether th receiver level/s change by less than 0.1 dB when
halving all sections. If the change is larger, the halved section length has to be
used.
When enabled, this condition is checked iteratively for all receivers (but not
for building evaluations and grid points) until the condition is met.
Consequently, at least three steps of processing runs are required to check
this condition referring to the source‘s segmentation.
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Chapter 6 - Calculation
6.2.11.2 Schall 03 (2014)
Additional
Information
When calculating Abar according to equation (19) in /26/ the term Drefl
representing the
Calculation of Abar
„level correction for reflecting noise barriers at a distance ds <= 5 m with an
absorbent base with height habs above the railhead“ (translation from
German)
is automatically considered by CadnaA. This requires that two barrier objects
are used to model this situation: one modeling the absorbent base and - when
looking from the source side - a second one modeling the reflecting barrier
behind it.
In order to distinguish whether a barrier has to be regarded as absorbing or
reflecting the following criteria apply:
•
Absorption Coefficient Alpha < 0.2: „reflecting“
•
Absorption Coefficient Alpha > 0.6: „absorbing“
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Chapter 6 - Calculation
6.2.11.2 Schall 03 (2014)
6
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Chapter 6 - Calculation
6.2.11.3 Nordic Prediction Method (1996)
6.2.11.3
Nordic Prediction Method (1996)
6
Dialog Configuration, tab „Railroad“ for Nordic Prediction Method (1996)
With this option deactivate the maximum order of reflection is specified via
the „Reflection“ tab (see chapter 6.2.8 "Reflection Tab").
Calc exactly one
reflection order
Any entered railway correction will be considered upon calculation. Thus, to
consider no railway correction a value of 0 dB has to be entered.
Railway Correction
(dB)
The A-weighted maximum levels LAFmax and LmaxF are additional descriptors
for railway noise in Nordic Prediction Method /72/. The different corrections are calculated in complete analogy with those of the A-weighted equivalent continuous sound pressure level LA,eq, but a different emission
parameter is used (see chapter 2.6.4 "Nordic Prediction Method 1996").
Calc maximum PassBy-Level

Besides the emission level, the propagation models for Leq and Lmax calculations differ as well.
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Option LmaxM/LmaxF
Chapter 6 - Calculation
6.2.11.3 Nordic Prediction Method (1996)
In CadnaA, the two A-weighted maximum sound pressure levels, LmaxM (energy average over train length) or LmaxF (highest level with weighting „Fast“)
can be calculated (see chapter 2.6.4).

The option „Diesel“ has to be set accordingly for each railway group/
train class on the dialog Library: Train Class (see chapter 2.6.12 "Train
Class Libraries", section "Application Nordic Prediction Method").
In order to calculate maximum levels, CadnaA moves a line source for each
train class in the train classes list of the railway object. This line source has
the sound power level and length as specified in the list. This source is moved
according to its speed and specified sampling interval (see below). The maximum level for this line source for each position with the specified sound
power level and length is calculated.
6
Sampling Interval (s)
In order to determine the highest level, CadnaA shifts the source along the
road in steps based on the sampling interval (in seconds). The default value
for the sampling interval is 0.1 seconds.
Consequently, the resulting distance difference between two source positions
is:
s  v  tsampling 
1000
3600
where
s: distance steps (m)
v: speed (km/h), as entered on dialog Railway
t: sampling interval (s)

Displaying rays (see chapter 5.1) and the calculation protocol (see chapter 6.5) do not make sense with maximum levels as the radiating points
are defined by the sampling time. The rays coming from points outside
result from the calculation procedure (in case the option „Extrapolate
trains to 1/2 length on both sides of rail“ is activated, see below).
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Chapter 6 - Calculation
6.2.11.3 Nordic Prediction Method (1996)
By default, this option is activated. In this case, when calculating the
maximum pass-by level, the length of each train class on the track is
extrapolated by half of its length beyond the first and the last point of the
drawn railway object to cope with segmented railways (e.g. due to different
maximum speeds).
By deactivating this option, the train length will not be extrapolated beyond
the first and the last point of the railway object. Deactivating this option may
cause a substantial level decrease for receivers/grid points near the end of the
rail source and at curves (see example below).
option activated
option deactivated
For a receiver in the center region of the rail source the levels do not differ.
option activated
option deactivated
For a receiver near the end of the rail source the resulting levels may differ substantially.
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Option „Extrapolate trains
to 1/2 length on both
sides of rail“
6
232
6
Chapter 6 - Calculation
6.2.11.3 Nordic Prediction Method (1996)

Instead, with the option deactivated, each railway object could be
extended manually to overlap with the next railway object making up
the railway track. However, this would require a separate railway object
for each train class in order to extend the source line properly with
respect to the train length of each class.
Other Properties: See
Industry
This hint refers to the following settings on the „Industry“ tab:
Use Non-Standard
Reference Time D/E/
N
With this option activated the time intervals and penalties on „Reference
Time“ tab are applied in the calculation.
6
•
•
•
lateral diffraction
if distance smaller
temperature/relative humidity
As the specification of emission of NPM is based on the traffic data within
24 hours, the values have to be corrected when using daily periods D/E/N
with END-calculations /121/. The correction for each octave band is:
L 'wo , D / E / N  L 'wo 10 lg
tD / E / N
dB
24
where
L’w0, D/E/N: octave band emission level in period D/E/N of length tD/E/N (in hours)
L’w0: octave band emission level for 24 hours
Example
For a daily period D of 12 hours the following correction applies:
L 'wo , D  L 'wo  10 lg

12
dB  L 'wo  3 dB
24
The values displayed on the „Reference Time“ tab (D/E/N=12/4/8 h)
will be updated based on the defined time periods DEN.
Further Information
Combined Assessment
Road/Railway
see chapter 6.2.10.2, section "Further Information"
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Chapter 6 - Calculation
6.2.11.4 CRN
6.2.11.4
CRN
6
Dialog Configuration, tab „Railroad“ for CRN
When the option „Use Non-Standard Reference Time“ is activated the time
intervals and penalties on the „Reference Time“ tab are taken into account in
the calculation.
Railway noise - according to the majority of standards/guidelines - is
calculated just for two daily periods: day and night. When doing calculations
with respect to END (Environmental Noise Directive /121/), however, this
option has to be activated to consider the number of trains (or the emission
parameter) during the Evening period as well.
see also:
chapter 6.2.4 "Reference Time Tab"
chapter 6.2.5 "Evaluation Parameters Tab"

The values displayed on the „Reference Time“ tab (D/E/N=12/4/8 h)
will be updated based on the defined time intervals (hours Day/
Evening/Night).
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Reference Time
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6
Reflection via
Correction (1.5 dB),
NOT via mirror
sources
Chapter 6 - Calculation
6.2.11.4 CRN
CRN clause 31.2 /82/ specifies that the reflection from buildings or other
reflecting objects (e.g. barriers) on the opposite side of the road have to be
considered by a correction of 1.5 dB depending on the angle of the reflecting
object/s seen from the receiver. The value of 1.5 dB occurs in case the entire
length of the road has reflecting buildings (i.e. is the maximum reflection correction).
For more details and examples see chapter 6.2.10.6 "CRTN", section "Reflection via Correction (1.5 dB), NOT via mirror sources".
6
Additional
Information
Facade Effect
CRN specifies in clause 31.1 that for calculations of the noise level at a distance of 1 metre in front of a façade a correction of +2.5 dB has to be made.
CadnaA does not apply this correction automatically for the time being as
this CRN-specification do not match the normal approach when calculating
façade reflections.
for more details and examples see chapter 6.2.10.6 "CRTN", section "Facade
Effect"
Screening Effect
In CRN, negative path differences cause screening (see chart 6a in /82/).
This means that a substantial screening correction may result with small path
differences z (0<z<0.4 m) in situations where the ray is not intersecting with
an obstacle, but just passing above its top edge („illuminated zone“).
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6.2.11.5 SRM II
6.2.11.5
6 235
SRM II
The implementation follows the procedures as defined by the EU-Interim
Report /2/ and the EC-Recommendation L 212/49 /107/. Both refer to
edition 1996 of the „Reken- en Meetvoorschriften Railverkeerslawaai '96“ /
81/ and not to more recent editions.
6
Dialog Configuration, tab „Railroad“ for SRM II
All emission sources are placed at 0.5 m above the railhead instead of
applying the sub-source heights as defined in the train class.
option deactivated
(for train classes C9 and C9r only)
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All Emissions at 0.5
m above railhead
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Chapter 6 - Calculation
6.2.11.5 SRM II
Railway Correction
(dB)
Any entered railway correction will be considered upon calculation. Thus, to
consider no railway correction a value of 0 dB has to be entered.
Use Non-Standard
Reference Time
D/E/N = 12/4/8
With the option „Use Non-Standard Reference Time“ deactivated the
following time interval lengths will be considered: Day (D)=16 hours,
Night (N)=8 hours. When this option is activated the time intervals and penalties on the „Reference Time“ tab (see chapter 6.2.4) are taken into account.
This option has to be activated for calculations according to END
(Environmental Noise Directive /121/) in order to consider the number of
trains (or the emission parameter) during the Evening period as well.
6

The values displayed here are updated based on the defined time intervals DEN on the „Reference Time“ tab.
Air Absorption accord.
to ISO 9613-1
In SRM II the air attenuation is based on spectral data at a temperature of
10°C and a relative humidity of 80%. In CadnaA, with activating this option
the air absorption can, alternatively, be calculated according to ISO 9613-1 /
8/.
Meteorological
Correction Cmet acc.
to ISO 9613-2
SRM II defines a meteorological correction term CM. The equations used to
determine CM are identical to the equations used in ISO 9613-2 to determine
Cmet. However, instead of the variable C0 an upper limit of 3.5 dB is used.
In order to calculate long-term levels this option enables to replace the 3.5
dB by C0 and using the calculation procedure for Cmet as established by ISO
9613-2 /8/.
Other Properties: See
Industry
This hint refers to the settings on the „Industry“ tab:
•
•
•
lateral diffraction
if distance smaller
temperature/relative humidity
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Chapter 6 - Calculation
6.2.11.6 NMPB-Fer 1996
6.2.11.6
NMPB-Fer 1996
6
Dialog Configuration, tab „Railroad“ for NMPB-Fer 1996
With the option „Use Non-Standard Reference Time“ deactivated the
following time interval lengths will be considered: Day (D)=16 hours,
Night (N)=8 hours. When this option is activated the time intervals and penalties on the „Reference Time“ tab (see chapter 6.2.4) are taken into account.
Use Non-Standard
Reference Time D/E/
N
This option has to be activated for calculations according to END
(Environmental Noise Directive /121/) in order to consider the number of
trains (or the emission parameter) during the Evening period as well.

The values displayed here are updated based on the defined time intervals DEN on the „Reference Time“ tab.
The emission model of NMPB-Fer considers two emission heights.
Activating this option will put all emission to a common height of 0.8 m
above railhead.
All Emissions at 0.8m
above railhead (no
source at 0.05m)
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
Meteorology
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Chapter 6 - Calculation
6.2.11.6 NMPB-Fer 1996
Note 1 - „Favorable conditions“ are such which facilitates the propagation of sound (i.e. which
are likely to cause a higher sound pressure level at the receiver point than with a moderate situation). This situation makes use of the (spectral) ground attenuation for moderate downwind as
specified by ISO 9613-2 /8/.
Note 2 - By the condition „homogène“ the contrary is assumed, the propagation situation is now
neither downwind, nor moderate. The rays are straight lines, not accounting for any atmospheric
influence. This kind of meteorological situation has been applied by all former prediction models
used in France.
6
Evening Values = Day
Values
With this option active the daytime values will be applied for the Evening period as well.
List Box Locations
The list box offers a variety of predefined locations (within France)
combined with respective data for the percentage of favorable conditions.
For more details see chapter 6.2.10.3, section "List Box / Locations".

No hint is possible here what percentage may apply to an unknown
location when just having a general description of the local orography.
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Chapter 6 - Calculation
6.2.11.7 NMPB-Fer 2008
6.2.11.7
6 239
NMPB-Fer 2008
6
Dialog Configuration, tab „Railroad“ for NMPB-Fer 2008
With the option „Use Non-Standard Reference Time“ deactivated the
following time interval lengths will be considered: Day (D)=16 hours,
Night (N)=8 hours. When this option is activated the time intervals and
penalties on the „Reference Time“ tab (see chapter 6.2.4) are taken into
account.
Use Non-Standard
Reference Time D/E/
N
This option has to be activated for calculations according to END
(Environmental Noise Directive /121/) in order to consider the number of
trains (or the emission parameter) during the Evening period as well.

The values displayed here are updated based on the defined time
intervals DEN on the „Reference Time“ tab.
The emission model of NMPB-Fer 2008 considers multiple emission heights.
Activating this option will put all emission to a common height of 0.0 m
above railhead.
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above railhead
240
6
Meteorology
Chapter 6 - Calculation
6.2.11.7 NMPB-Fer 2008
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
Note 1 - „Favorable conditions“ are such which facilitates the propagation of sound (i.e. which
are likely to cause a higher sound pressure level at the receiver point than with a moderate
situation). This situation makes use of the (spectral) ground attenuation for moderate downwind
as specified by ISO 9613-2 /8/.
Note 2 - By the condition „homogène“ the contrary is assumed, the propagation situation is now
neither downwind, nor moderate. The rays are straight lines, not accounting for any atmospheric
influence. This kind of meteorological situation has been applied by all former prediction models
used in France.
6
Evening Values = Day
Values
With this option active the daytime values will be applied for the Evening
period as well.
List Box Locations
The list box offers a variety of predefined locations (within France)
combined with respective data for the percentage of favorable conditions.
For more details see chapter 6.2.10.4, section "List Box / Locations".

No hint is possible here what percentage may apply to an unknown
location when just having a general description of the local orography.
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Chapter 6 - Calculation
6.2.11.7 NMPB-Fer 2008
see chapter 6.2.10.4, section "Calc Atalus"
Calc Atalus
By the factor Ch the attenuation by „pure diffraction“ is modified for barriers
(not for terrain contours). Activating this option may lead to a lower barrier
attenuation (for details see /80/).
Use Ch in Calculation
of Abar
see chapter 6.2.10.4, section "Use reference DLL"
Use reference DLL
Specify the number of screen-body-interactions to be considered in the
calculation. Consider that a single interaction means two reflections, one at
the screen and the other at the train‘s body.
Number of ScreenBody-Interactions
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6.2.11.7 NMPB-Fer 2008
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Chapter 6 - Calculation
6.2.11.8 CNOSSOS-EU
6.2.11.8
6 243
CNOSSOS-EU
6
With this option deactivated the following time interval lengths will be considered: Day (D)=16 hours, Night (N)=8 hours. When this option is
activated the time intervals and penalties on the „Reference Time“ tab (see
chapter 6.2.4) are taken into account.
Use Non-Standard
Reference Time D/E/
N
This option has to be activated for calculations according to END
(Environmental Noise Directive /121/) in order to consider the number of
trains (or the emission parameter) during the Evening period as well.

The values displayed here are updated based on the defined time intervals DEN on the „Reference Time“ tab.
The emission model according to CNOSSOS-EU considers multiple
emission heights. Activating this option will put all emission to a common
height of 0.5 m above railhead.
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above railhead
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6
Meteorology
Chapter 6 - Calculation
6.2.11.8 CNOSSOS-EU
Via the button „Meteorology“ the percentage of „favorable conditions“ in
wind sectors stepped by 20° can be specified for the time periods D/E/N
separately. The percentage refers to the assessment interval, usually an entire
year.
6
For further details on this dialog, see chapter 6.2.10.4, section "Meteorology".
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Chapter 6 - Calculation
6.2.11.9 FTA/FRA
6.2.11.9
6 245
FTA/FRA
6
Dialog Configuration, tab „Railroad“ for FTA/FRA
All emission sources are placed at 0.3 m above the railhead instead of
applying the sub-source heights as defined in the train class. Consequently,
also the sub-source height at 0.05 m is not used.

Consider that the default height of the object Railway is 0.6 m which
requires to be changed to a height of 0.0 m to meet the FTA/FRA
specifications.
In case this option is deactivated time intervals Day (D)=15 hours, Evening
(E)=0 hours, and Night (N)=9 hours will be considered.
With this option activated the allocation of hours as specified on the
„Reference Time“ tab will be used instead.

All Emissions at 0.0
m above railhead
The values displayed here are updated based on the defined time intervals DEN on the „Reference Time“ tab.
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Reference Time D/E/
N
246
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Railway Correction
Chapter 6 - Calculation
6.2.11.9 FTA/FRA
This option enables to address a general correction or penalty for the receiver
level:
SPLwith corr = SPLw/o corr - (Railway Correction)
In order to apply no railway correction a value of 0 dB has to be entered.
Calc maximum PassBy-Level
The calculation of the maximum pass-by-level is not covered by FTA/FRA
calculation procedures. Nevertheless, CadnaA offers to calculate this maximum level by iteration based on the Leq-based emission. The same propagation model as with Leq calculations according to FTA/FRA is used. To this
end, each train class with its corresponding length is moved along the object
„Railway“ according to its speed and sampling time (see below). The maximum level for this line source for each position with the specified sound
power level and length is calculated.
Sampling Interval (s)
In order to determine the highest level, CadnaA shifts the source along the
railway in steps based on the sampling interval (in seconds). The default value
for the sampling interval is 1 second.
Option „Extrapolate trains
to 1/2 length on both
sides of rail“
By default, this option is activated. In this case, when calculating the
maximum pass-by level, the length of each train class on the track is
extrapolated by half of its length beyond the first and the last point of the
drawn railway object.
6
By deactivating this option, the train length will not be extrapolated beyond
the first and the last point of the railway object. Deactivating this option may
cause a substantial level decrease for receivers/grid points near the end of the
rail source and at curves (see example below).
For illustration of this effect see chapter 6.2.11.3.
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Chapter 6 - Calculation
6.2.11.9 FTA/FRA
Additional
Information
According to the FRA/FTA-reports, the ground factor G for barrier
attenuation is calculated from the effective height Heff (see figure 5-3 of the
FRA-report /92/ or figure 6-5 of the FTA-report /91/). As this simplified
concept does not work properly in complex situations CadnaA does not
apply this computation scheme.
Barrier Attenuation
In contrary, the ground factor G for barrier attenuation is calculated using
the mean height concept of ISO 9613-2 /8/ resulting in a smooth value of
Aground even with complex terrain structures in conjunction with multiple
obstacles in the ray's path (see ISO 9613-2, section 7.3, for details).
6
The barrier insertion loss Ashielding is based on the equations in table 5-1, page
5-14 of the FRA-report /92/. For source types LOCO and CAR the barrier
insertion loss is calculated using the equations for "propulsion sub-sources"
(type PROP).
The ground attenuation Aground for the sub-sources wheel-rail and propulsion
is calculated using the equations on page 5-16 of the FRA-report /92/. For
source types LOCO and CAR the equations for "propulsion sub-sources"
(type PROP) are applied. Aerodynamic sub-sources receive no ground
attenuation at all.
Ground Attenuation
The excess shielding (as of table 5-5, page 5-18, FRA-report /92/) by rows of
buildings (in CadnaA called "built-up areas") and by dense tree zones (in
CadnaA called "foliage") are not considered - for the time being.
Excess Shielding
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Chapter 6 - Calculation
6.2.11.9 FTA/FRA
6
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Chapter 6 - Calculation
6.2.12 Aircraft Tab
6.2.12
6 249
Aircraft Tab
This tab is only relevant in conjunction with the CadnaA option FLG . See
the specific manual on „Aircraft Noise Calculation“.
6
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Chapter 6 - Calculation
6.2.12 Aircraft Tab
6
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Chapter 6 - Calculation
6.2.13 Optimizable Source Tab
6.2.13

Optimizable Source Tab
This tab is only available when having the option BPL installed.
6
On tab „Opt.Src.“ three different options referring to the propagation
conditions applied in conjunction with optimizable sources (see chapter 2.9)
can be specified.
•
With this option, the calculation of propagation of optimizable sources
apply the selected industry standard or guideline (see dialog
Calculation|Configuration, „Country“ tab, see chapter 6.2.1).
like Industry Sources
•
With this option, the propagation just considers geometrical divergence in
a free-field using:
Free field (4*pi*r²)
SPL = PWL - 11 dB - 20 lg r
In this case, there are no other damping effects, like air absorption and
diffraction, considered.
•
With this option, the propagation just considers geometrical divergence in
a semi-free-field using:
SPL = PWL - 8 dB - 20 lg r
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Chapter 6 - Calculation
6.2.13 Optimizable Source Tab
Again, there are no other damping effects considered.
 option „r is horizontal (2D) distance“: With this option activated the
2D-distance as projected to the xy plane is used to calculate the
geometrical divergence. This setting complies with the requirement of
DIN 45691 /34/.
Mixed parameters in
conjunction with
option BPL
Please note that the optimization of sound power levels per m² using the option BPL can be carried out only for the daytime level Ld and the night-time
level Ln (list box „Day/Night“ on the dialog Optimizable Source). In particular, the optimization of mixed evaluation parameters (like Lde or Lden) is
excluded - for the time being.
Editing Iteration
Increment
By default, the iteration increment applied with optimizable sources sources
is 0.1 dB.
6
In order to optimize for the calculation runtime, particular at a large number
of BPL sources, the iteration increment can be set using a local text block
(see chapter 12.5, named BPL).
Example
Name: BPL
Text: DELTA_L = 1.0
In this case, an iteration increment of 1.0 dB will be used when optimizing
BPL sources.
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Chapter 6 - Calculation
6.3 Adjustment of the Configuration
6.3
Adjustment of the Configuration
Starting from the CadnaA release 4.6.153 the previous configuration options
•
„Special Reference Time for Industry (min)“ on the „Reference Time“
tab) and
•
„Compatibility Mode for Industry“ on the „Evaluation Parameters“
are no longer available.
These changes are caused by the implementation of diurnal patterns for
industrial sources (see chapter 2.1.1, section "Addressing Diurnal Patterns"
and chapter 12.3).
6
When loading files saved with previous releases of CadnaA an automatic adjustment of the configuration settings occurs in order to ensure that - even
after dropping these options - the same calculation results are obtained.
Below some examples for typical configuration adjustments are explained:
•
case 1: file with industrial sources only and the compatibility mode activated
Message
Remarks
The option "Compatibility mode for Industry" is disabled
and the evaluation parameters are changed to:
1: Ld --> Lde
The evaluation parameter
can be changed directly
from Ld to Lde.
The "Special Reference Time for Industry (min)" with
Day: 780.00 min, Evening: 180.00 min, Night: 60.00 min
will be transferred to the Allocation Hour - Periods (on
"Ref.Time" tab) by: 13 h D, 3 h E, 1 h N
The transfer of the special
reference time for industry
to the allocation HoursPeriods is directly possible.
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6.3 Adjustment of the Configuration
•
case 2: file with industrial sources only and the compatibility mode NOT
activated
Message
Remarks
no message regarding "Compatibility mode for Industry"
displayed as not used (e.g. with eval. parameters 1: Lde, 2: Ln
set)
The "Special Reference Time for Industry (min)" with
Day: 780.00 min, Evening: 180.00 min, Night: 60.00 min
will be transferred to the Allocation Hour - Periods (on
"Ref.Time" tab) by: 13 h D, 3 h E, 1 h N
6
•
-
see case 1
case 3: file with industrial and other source types and the compatibility
mode activated, while the option „Use Non-Standard Reference Time D/
E/N“ (for railway and/or aircraft noise) is activated
Message
Remarks
The option "Compatibility mode
for Industry" is disabled and the
evaluation parameters are
changed to:
1: Ld --> (indde++strd++
schd++spod++flgd)
The new evaluation parameter 1 is represented by the
energetic summation of all source types (with Lde for
industry (indde, Day/Evening mixed level) and sports
tennis source Day (spod).
This representation is required as esp. for roads and
railways the Ld was calculated as daytime level, while for
industrial sources, however, the Lde was calculated.
The "Special Reference Time for
Industry (min)" with Day:
780.00 min, Evening: 180.00
min, Night: 60.00 min
will be transferred to the Allocation Hour - Periods (on
"Ref.Time" tab) by:
13 h D, 3 h E, 8 h N
A warning message is displayed, as for rail or aircraft
noise the option "Use Non-Standard Reference Time
D/E/N" was activated. This causes that the entered
special reference times for industry can not be modified
in a compatible way without altering the settings for
railway during nighttime.
NOTE - This incompatibility, however, existed in the
old file already and, therefore, the problem is not due to
the modification of the configuration.
WARNING: Special Reference
Time is not compatible with
"normal" reference time!
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6.3 Adjustment of the Configuration
•
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case 4: file with industrial and other source types and the compatibility
mode activated, while the option „Use Non-Standard Reference Time D/
E/N“ (for railway and/or aircraft noise) is NOT activated
Message
Remarks
The option "Compatibility mode for Industry" is disabled
and the evaluation parameters are changed to:
1: Ld --> (indde++strd++schd++spod++flgd)
see case 3
The "Special Reference Time for Industry (min)" with
Day:
780.00 min, Evening: 180.00 min, Night: 60.00 min
No warning is displayed
because the option "Use
Non-Standard Reference
Time D/E/N" was not
activated. This means that
the allocation of hours is
not relevant for source
types Railroad and Aircraft.
It is used: D: 16 h, N: 8 h.
will be transferred to the Allocation Hour - Periods (on
"Ref.Time" tab) by:
13 h D, 3 h E, 1h N
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6.4 Selecting Data for the Calculation
6.4
Selecting Data for the Calculation
For a partial calculation, deactivate existing objects. Various tools, which may
be combined, are available for this purpose which are described below.
Objects can be included or excluded from the calculation by
•
•
•
activating/deactivating individual objects via the ID-code on the object’s
edit dialog (see manual "Introduction to CadnaA") or
by using groups (see chapter 14.3) or
by using variants (see chapter 14.2).
Exclude Objects for
the calculation
6
Deactivated objects are displayed by default with dashed lines. This can be
changed on dialog Options|Appearance (see chapter 9.5).
By the object „Calculation Area“ an area can be defined being used for the
grid calculation (see chapter 5.3). Several calculation areas can be defined in a
project file. If no calculation area has been defined the entire limits are used
when calculating the grid (see chapter 9.1).
Calculation Area
With the option „Exclude Area“ on dialog Calculation Area it is possible to
exclude a calculation area laying inside the existing calculation area. Inside
this area the grid is not calculated.
Exclude Area
All calculation areas are listed on menu Tables|Other Objects|Calculation
Area. The sequence of the data sets determines the sequence of calculation.
Table Calculation
Area
For these calculation areas, CadnaA will take into account all objects, even
outside the calculation area, unless they are deactivated.
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Calculation Time
Chapter 6 - Calculation
6.4 Selecting Data for the Calculation
The total area of all calculation areas in a project file determines the time
required for the calculation. It is therefore advisable, for the first test, to
specify a large spacing between the receiver points via menu Grid|
Properties, in order to watch the progress of the calculation once it has been
started and, if required, to abort the calculation and restart it with a different
spacing between the receiver points.
6
The level distribution was calculated for this calculation area
with all objects within the limits.
Calculate Grid
The calculation for a calculation area is started via the menu
Grid|Calculate Grid (see chapter 5.3.3). If several calculation areas exist,
these are calculated one after the other.
see also Check Consistency Chapter 5.1.1.
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6.5 Calculation Protocol
6.5
Calculation Protocol
The calculation protocol (Calculation|Protocol dialog) for receiver points
is generated during runtime and requires, therefore, to recalculate the levels at
receivers after activating this option (via the symbol
on the toolbar).
6
The calculation protocol shows the relevant sound power levels (Lw resp.
L‘w), the attenuations, and the receiver levels (Lr) for each ray path for the
time periods Day, Evening and/or Night. Note that there no protocol exists
for mixed receiver levels (e.g Lde or Lden). These mixed levels are calculated
from the levels Ld, Le and Ln afterwards (including the entered penalties, if
any).
Dialog Options
With the option „Write Protocol“ activated all intermediate results calculated
at receivers (see chapter 5.1) are written to a protocol file upon recalculation.
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Protocol File
Chapter 6 - Calculation
6.5 Calculation Protocol
By default, the filename <cadnaafilename>.cnaprot is used. First,
save the CadnaA file to a directory in order to specify the path to write the
protocol file to.
Use the „Select“ button you may specify an alternative filename and file path.
Button „Print“
By clicking the „Print“ button in the Print|Protocol dialog is opened
enabling to specify the printer settings and the page layout (check for the
analogous options in the Print Report dialog, see chapter 13.2.1).
On the „Print Range“ all receiver points are listed and can be selected
individually by activating the option „Selected Paragraphs“. Furthermore, the
configuration settings can be printed as well.
6
•
Use the „Preview“ button to display the selected paragraphs on the
CadnaA Print Preview dialog (see chapter 13.2.3).
•
Clicking the „Print“ button will start to print via the selected printer
immediately.
Regarding the protocol abbreviations used in the protocol see the manual
„Attributes, Variables, and Keywords“, chapter .
Button „Export“
Clicking the „Export“ button enables to export the protocol file in ASCII
text format. To this end, after the calculation at receivers, specify a filename
and select a directory. By clicking „Save“ the protocol file is exported using
the currently set table columns. The exported file can be opened with a text
editor and be edit, if necessary.
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Options
see below, option „Tables“
Button „Tables“
The selected time range determines whether the protocol is shown for all
days periods D/E/N or just for a specific period.
Period
By default, the option „(all)“ is selected. In this case, the protocol file lists
separate rows for each time period D/E/N, provided the emission differs
within each of the periods. When the emission is equal within all periods D/
E/N, however, just a single protocol row using the identifier „DEN“ is displayed.
6
Examples: see next page
By activating this option the protocol will just list those partial levels which
are larger or equal to the entered value. Otherwise, these protocol lines will
be suppressed. This option is deactivated by default.
Option „Minimum Value
for Lr“
Example: By specifying a minimum value of 0.0 dB no negative partial level
will be displayed.
With this option activated, not the entire calculation for each frequency band
will be logged. Instead, the levels are calculated applying the A-weighting to
frequency-dependent attenuation terms.

When having multiple instances of CadnaA running with all instances
writing to same the protocol file assignment problems may occur (e.g.
<cadnaafilename>.cnaprot). Make sure that the displayed
protocol file is the protocol of the last calculation.
see also: chapter 6.5.1 Compact Protocol
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6.5 Calculation Protocol
Examples:
6
EXAMPLE 1: point
source with the
same emission time
in periods D and E,
but different emission in period N.
In case option „(all)“
is selected, the protocol will show separate rows for each
time period.
For railway, separate
rows for time periods are always displayed.
NOTE: Option
„minimum value for
Lr: 0.0 dB“ ON
EXAMPLE 2: point
source with the
same emission in all
time periods D/E/
N.
In case option „(all)“
is selected, the protocol will list lines
marked by „DEN“
which apply to each
of the time periods
D/E/N.
NOTE: Option
"minimum value for
Lr: 0.0 dB" A
By selecting the period „Day“ instead of „(all)“ the protocol in example 1
would just list the rows marked by „D“ for both types of sources, in example
2, however, would still show „DEN“ for the point source, but rows marked
„D“ for the railway source.
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For industrial sources, the protocol shows the column K0. The displayed
value depends on the configuration setting for option „Ground Absorption“
on the „Industry“ tab (see chapter 6.2.9):
•
Column K0 for
industrial sources
(directivity index)
For ground absorption models considering the increase in sound power
level of the source due to ground reflections near the source within the
ground absorption Aground, the column K0 just shows the value „K0
without ground“ as entered on the respective source dialog.
An example is the spectral ground absorption model of ISO 9613-2 /8/
(in this example K0 = K0 without ground = 3 dB):
6
This also applies to propagation models which do not consider ground
reflections near the source at all or in a different way.
•
For ground absorption models considering the increase in sound power
level of the source due to ground reflections near the source separately
(so, besides the pure ground absorption Aground), the column K0 shows
the sum of the value „K0 without ground“ as entered on the respective
source dialog and the calculated directivity index (e.g. K0 in VDI 2714,
Domega in ISO 9613-2).
An example is the non-spectral ground absorption model of ISO 9613-2
/8/ (K0 = K0 without ground + Domega, in this example 3 dB + 2.9 dB
= 5.9 dB):
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Option „Tables“
Chapter 6 - Calculation
6.5 Calculation Protocol
Clicking this button opens a dialog enabling to edit the columns displayed on
the protocol tables.
6
The protocol has a predefined column structure for each calculation standard
or guideline. The calculation standards displayed depend on the current hardlock configuration.
The dialog range „Standard“ is divided into four columns for standards
depending on source types industry, road, railway and aircraft noise. Click on
a designation in order to display the corresponding predefined table format
in the dialog range „Preview“. The column headings in the preview are
adjusted accordingly (see Chapter 6 - Protocol Abbreviations in the manual
„Attributes, Variables, and Keywords“).
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On this dialog, the content and the format of the respective protocol table
for a specific standard can be edited. By default CadnaA applies a predefined
format. User-defined protocol table formats can be saved and opened.
Editing the Protocol Table
The basis of the format definition are the protocol table attributes (see
below).
6
For further features of this dialog, see chapter 11.1.2 "Editing Object Tables".
Select „User-defined Table“ and double-click into a table row to edit the column or select the command Edit from the context menu. This opens the dialog Table Column enabling to enter headlines and to define the column
content.
For further features of this dialog see chapter 11.1.2 "Editing Object Tables",
section "Dialog Table Column".
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Attributes for Protocol
Tables
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Chapter 6 - Calculation
6.5 Calculation Protocol
The following protocol table attributes are available:
Attribute
Description
NUM
number of the ray
HSRC
Handle Source (internal object No.)
HRCV
Handle Receiver (internal object No.)
NORM
number of the standard (internal)
PART_SRC
number of the partial source (internal)
X
x-coordinate
Y
y-coordinate
Z
z-coordinate
GROUND
ground height
REFLORD
order of reflection
DEN
designation of time period DEN, D, E, N
FTYP
frequency type (S = spectrum, C = compressed spectrum (single
value), A = A-weighted level)
FREQ
frequency (third-octave or octave)
LW
sound power level (linear)
LW_A
A-weighted sound power level
LR
partial level, receiver (linear)
LR_A
A-weighted partial level, receiver
C_LENAREA
correction length/area
C_OPTIME
correction for operating time
C_K0
directivity index (sum of value entered for „K0 w/o ground“ and of
K0/D resulting from propagation calculation - if any)
C_DIR
correction directivity
C_DIV
correction divergence
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6.5 Calculation Protocol
C_AIR
correction air absorption
C_GROUND
correction ground attenuation
C_BAR
correction barrier attenuation
C_BEB
correction attenuation due to built-up areas
C_BEW
correction attenuation due to foliage
C_PHI
correction aspect angle
C_MET
correction meteorology
C_DREFL
correction for multiple reflections
C_STEIG
correction gradient correction
C_RL
correction reflection loss
C_CONST
constant (internal)
C_C1
correction C1 (link depends on standard, see table below)
C_C2
correction C2 (link depends on standard, see table below)
C_C3
correction C3 (link depends on standard, see table below)
C_C4
correction C4 (link depends on standard, see table below)
C_C5
correction C5 (link depends on standard, see table below)
C_C6
correction C6 (link depends on standard, see table below)
below attributes for geometry:
G_DIST
3D distance (m)
G_HM
average height (m)
G_SCR_Z
path difference z (m)
G_SCR_DSS
3D distance source - first diffracting edge (m)
G_SCR_DSR
3D distance last diffracting edge - receiver (m)
G_SCR_E
distance first - last diffracting edge (m)
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6.5 Calculation Protocol
G_SCR_DPAR
distance source - rcvr, measured parallel to diffr. edge (Schall03-2013,
m)
G_LENBEB
propagation path length through built-up area (m)
G_LENBEW
propagation path length through foliage (m)
below attributes for aircraft noise:
6
F_ACFT
aircraft group
F_CORR_NR
number of corridor
F_SIGMA
arc length (m)
F_SEG_S
segment length, start (m)
F_SEG_E
segment length, end (m)
F_D
arc length (m)
F_Z
additional level (dB) / power setting
F_V
speed (m/s)
F_H
height at fly-over point (m)
F_TIME_A
time aircraft (s)
F_TIME_R
time receiver (includes propagation time, s)
F_RHO
perpendicular distance (m)
F_CORRW
corridor width (m)
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corrections C1..C6 depending on standard:
Standard
C_C1
C_C2
C_C3
C_C4
C_C5
C_C6
Concawe
K5
-
-
-
-
-
AsolF
AdifF
-
-
-
-
K
-
-
-
-
-
DLka
DLts
-
-
-
-
Agr/bar/
reflN
Agr/bar/
reflF
-
-
-
-
Cball
-
-
-
-
-
A
-
-
-
-
-
AzB 08
SEL
Lmax
-
-
-
-
ECAC Doc.29 3rd Ed.
INM
CNOSSOS-EU
SEL
Adur
Arev
Aimp
-
-
NMPB-Ind-08
NMPB-Routes-96
NMPB-Routes-08
NMPB-Fer
NMPB-Fer-08
CNOSSOS-EU
RLS-90
STL 86
CRTN
Nordic Pred. Method
SonRoad
CRN
AzB 75
ECAC Doc.29
DIN 45684
ÖAL 24
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Open protocol file
using a SQL editor
Chapter 6 - Calculation
6.5 Calculation Protocol
The CadnaA protocol file (file extension cnaprot) is saved using the
SQLite database format which can be opened using a SQLite editor (e.g. DB
Browser for SQLite), see:
https://github.com/sqlitebrowser/sqlitebrowser/releases
Requirements & Support
6
Basic SQL knowledge is required in order to use the database browser
properly. Please consider that the CadnaA maintenance contract does not
cover the development or the debugging of SQL database queries. If you
need further assistance, please contact DataKustik to obtain a quote for this
service.
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6.5.1 Compact Protocol
6.5.1

6 271
Compact Protocol
The compact protocol is available just for industry sources calculated
according to ISO 9613.
Use the Compact Protocol to produce a single value for the effective
screening coefficient and the proportion of reflected sound, referred to the
overall source, line by line for each source, even extended sources such as
area or line sources.
When calculating, e.g., an area source with screening, the values with and
without a screen are calculated automatically, and the effective screening
coefficient is indicated as the difference Abar,eff.
Procedure:
•
For the compact protocol, generate a protocol via the menu command
Calculation|Protocol (see chapter 6.5).
•
Restart the calculation for receivers. The protocol file is written.
•
Then compress it using File|Export, Export format „Compact protocol“
and specify a filename.
•
Enter file name, CadnaA automatically adds the extension TXT.
•
Click OK to confirm.
Now, CadnaA creates an ASCII file containing TAB-separated data with the
following column headings:
Name
ID
Freq
LxT
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LxN
LrT
LrN
Refl
Abar,eff
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Chapter 6 - Calculation
6.6 Multithreading
6.6
Multithreading
CadnaA makes offers multi-threading and, thus, makes full use of the multi-
processor CPUs. Since all new desktop- and laptop-PCs use multi-core
CPUs, this will cut down calculation times significantly. CadnaA is prepared
to use up to 64 parallel processors (requires Option 64).

In CadnaA 32-Bit just up to 32 processors are available!
By default, the option „All available“ is selected on dialog
Calculation|Multithreading. Alternatively, CPU usage can be extended to
all processors or to a selection of processors.
Make your selections and close the dialog with OK. CadnaA will save the
settings and reload them after a restart.
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Chapter 6 - Calculation
6.6 Multithreading
CadnaA makes use of multi-threading for the following calculation tasks:
•
receiver points, as long as the calculation protocol is not activated (menu
Calculation|Protocol),
•
building evaluations or facade points, respectively, and
•
horizontal and vertical grids.
6
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6.7 Multiple Source Effect
6.7
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Multiple Source Effect
The dialog Multiple Source Effect (Calculation menu) enables to evaluate
different scenarios with respect to traffic noise impact by calculating the
„effect related substitute level“ according to the VDI guideline 3722-2 /44/.
Applying the assessment requires facade levels calculated using building
evaluations (see chapter 5.4) for road, railway and aircraft noise in separate
variants (see chapter 14.2) for the evaluation parameters Lden and Lnight and
the number of inhabitants per building (see chapter 3.1.1). The following
results are generated:
•
the „effect related substitute level“ at facade points and in the building
evaluation symbols,
•
the parameters Annoyed Persons (AP), Highly annoyed Persons (HAP), Sleep disturbed (SD) and Highly sleep disturbed persons (HSD) are written into string
variables stored on the Memo-Window of each building.

Industrial noise is neither included, nor assessed by the VDI guideline
3722-2 /44/.
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Points and Building
Evaluations
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Application to the
Grid and to Receivers
Chapter 6 - Calculation
6.7 Multiple Source Effect
Basically, the evaluation according to VDI guideline 3722-2 in CadnaA does
not refer to the grid or receiver points, since the number of persons AP/
HAP/SD/HSD is to be determined primarily.
In CadnaA, however, the „effect related substitute level“ can be calculated
on the grid and at receivers as well. To this end, select the formula expression
„f(x)“ from the „Evaluation Parameters“ tab (see chapter 6.2.5) and via the
double arrow (>>) from the parameter group „VDI 3722“ the evaluation
parameters Lden (DEN) and Ln (Night).
6
Now, the „Evaluation Parameters“ tab may look like this:
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6.7 Multiple Source Effect
Dialog Options
The following options are available:
•
VDI 3722: Calculation of the parameters Annoyed Persons (AP), Highly
annoyed Persons (HAP), Sleep disturbed (SD) and Highly sleep disturbed persons
(HSD) considering the noise impact of several sources types road, rail
and/or aircraft noise, based on the VDI guideline 3722-2:2013.
•
VDI 3722 (A7, A8, A15, A16): With this option, the method according to
the afore-mentioned edition of VDI 3722-2 is strictly applied using the
inverse functions (A7), (A8), (A15) and (A16) mentioned there. As a
mathematical error in these functions in VDI 3722-2 occurred an alternative method (i.e. the option „VDI 3722“) was implemented applying a
numerically correct inversion of the original functions (A1), (A4) and (A9)
and (A12). With regard to a possible revision of the guideline it is recommended, therefore, to use the option „VDI 3722“ instead.
•
Calculation Method
6
HAP: The noise evaluation method according to Miedema /88/ generates
three indicators: Highly Annoyed Persons (HAP), highly sleep disturbed
persons (HSD) and the statistical value of expectation of noise-induced
myocardial infarction (NMI).
Select for the noise types „Road“, „Railway“ and „Aircraft“ one of the
available variants to be used for the assessment. This requires that for up to
three noise types separate variants have to be enabled and calculated. By
selecting „(none)“ the respective noise type is not included into the HAP
calculation.
Select in line „Save total in“ the target variant (that is, another „empty“
variant) to be used to display the „effect related substitution level“ at the
facade points and on the building evaluation symbols. The calculation of the
substitution levels for Lden is based on the fraction HA and for Ln the fraction HSD. Note that no levels <42 dB(A) can be mapped for the substitution
level Lden.
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6.7 Multiple Source Effect

By selecting this variant and the evaluation parameters according to
VDI 3722 (see section "Application to the Grid and to Receivers"), the
„effect related substitution levels“ are displayed both on the grid, at
receivers and at facade points/building evaluation symbols.
Assignment of Evaluation
Parameters
The noise evaluation method according to Miedema and the procedure in VDI
3722-2 refers to the levels Lden and Lnight. Assign using these list boxes which
of the currently available evaluation parameters is linked to the two levels
Lden and Lnight. In case Lden and Ln have been chosen as the first and the
second evaluation parameter, no change is required.
Option "Detailed
Results"
If this option is activated, the evaluation occurs for the different noise types
individually as assigned by the variant and for total noise (e.g. HAProad,
HAPrail, HAPair, HAPtot etc.).
Option "Protocol File"
With this option activated, the results of the HAP calculation are written into
the specified text file. If necessary enter a file name and select the directory
via the file selector symbol.
Button OK
Clicking this button starts the evaluation and writes the results into the
Memo-Window of the buildings (and exported, with the option above
selected).
Button „Export“
Via this button, the calculation results at the facade points are exported to a
Shape file (ArcView *.shp). The geometry corresponds with the 3D-Shapeexport of facade points (see chapter 13.3.2), but here the results for the
various noise types are written to the following string variables (see dialog
Memo-Window of the auxiliary polygons):
6
•
•
•
NAME, BLDG_ID: name and ID of the facade point (or BuildEval)
RES_RECV_N: number of residents at the facade point (assuming
RES_RECV_N = EINW/(number of facade points)
evaluation parameters LP1 and LP2 for noise types R=road, RW=railway,
A=aircraft (in dB)
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6.7 Multiple Source Effect
In the first step, the source type specific building noise maps are calculated.
Procedure
In order to evaluate the grid and receivers as well, select the two VDI specific
evaluation parameters on the „Evaluation Parameters“ tab (see above).
•
Select the Lden as evaluation parameter 1 and Ln as evaluation parameter
2 via menu Calculation|Configuration.
•
Assign roads, railways and air routes each to a single variant (e.g. using the
short variant names ROAD, RAIL and AIR).
•
Define at least one further variant where the results of the multiple source
effect calculation according to VDI 3722-2 are written to.
•
Enter a building evaluation symbol at some location and enter on the
dialog part „Options“ the following values:
 Height of Storey (m): 1000 (accord. to VDI 3722 just facade points
at a single height are used)
 Height Rcvr EG above Ground (m): 4
•
Close the dialog by OK.
•
Generate the building evaluation symbol for all buildings to be considered
(via dialog Modify Objects, action „Generate Building Evaluation“).
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Chapter 6 - Calculation
6.7 Multiple Source Effect
•
Now, delete the initial building evaluation symbol used to specify the
height settings.
•
Calculate the facade levels for all or the variants to be considered (via
menu Calculation|Calc).
•
If necessary, start the grid calculation for all or selectable variants via the
menu Grid|Calculate grid.
In the second step is the parameters describing the multiple source effect are
calculated.
6
 Examples\06_Configuration\VDI 3722-2
•
Open the dialog Multiple Source Effect on the Calculation menu.
•
Select the calculation method and address the variants to the source types.
•
Specify the variant the „effect related substitute level“ shall be written to.
•
Address the evaluation parameters and start the calculation with OK.
On the Memo-Window of the buildings the calculated values are displayed.
These can be evaluated statistically using CadnaA specific procedures or in
tables or can be presented as a map by spatial averaging using ObjectScan
(see chapter 15.1).
Dialog Memo-Window of a building with text variables
showing resulting values according to VDI 3722-2
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see chapter 15.5
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6.7.2
QSI - Statistical Analysis
The "Requirements and Testing Conditions for statistical qualification of level differences" stated in DIN 45687 /33/, annex F (available in German only)
are implemented in CadnaA. To statistically evaluate the level differences
from two calculation runs with different configuration settings the 0.1-quantile and the 0.9-quantile are calculated and displayed (10%- resp. 90 %-value
of the distribution of the level differences).
6
The command QSI-Statistical Analysis is available via the menu Tables
|Miscellaneous. The evaluation may be applied to grid points, to facade
points or to points on lines of equal sound level (Iso-Lines).
Dialog QSI - Statistical Analysis
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The statistical evaluation in CadnaA considers all active receiver points (minimum number of receivers = 20). The additional requirement according to
annex F of DIN 45687 regarding a minimum horizontal distance of userdefined receivers of 2 m from sources and obstacles has to be ensured by the
user himself. When receivers are generated by CadnaA the minimum
horizontal distance will be respected automatically.
Specify which of the variants in the project file should be considered as reference configuration and as project configuration. Normally, the setting
„(default“)“ applies for the reference configuration which is defined globally
(see below, Reference Configuration). With the default reference configuration selected, the additional variant „REF“ (corresponding with variant V16)
will be listed on the list boxes „Reference Configuration“ and „Project
Configuration“ after calculation.
Assignment of
Variants
As far as the reference configuration is concerned the default values (setting
„Default“) can be applied or be altered by the user (setting „User defined“).
In the latter case the default reference configuration values will be listed in
the box upon click onto the button „Copy Default“. The parameters listed in
the table below are available for the time being..
Reference
Configuration
parameter (unit / value range)
variable/default value
maximum error (dB):
search radius (m):
grid interpolation on/off (1/0):
raster factor (-):
projection of line sources on/off (1/0):
projection of area sources /off (1/0):
order of reflection (1-20):
max. distance source-receiver (m):
ibid, interpolate from (m):
reflector-search radius source (m):
reflector-search radius receiver (m):
MAXERROR=0.0
SEARCHRAD=3000
RASTER_INT=0
RASTERFACT=0.5
PROJ_LQ=1
PROJ_FQ=1
REFLORDER=1
REFL_DMAX=3000
REFL_DMAXI=3000
REFL_RAD_S=3000
REFL_RAD_R=3000
The reference configuration settings can be changed by entering different
values for the parameters as required.
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Evaluation Parameter
Select the evaluation parameter used for the statistical evaluation. With setting „(current)“ the active performance parameter is used.
Test Points
DIN 45687, annex F, requires a minimum number of 20 receivers for the
evaluation.
use existing Receivers
In order to use the existing receivers shall, their ID must be changed to the
text string „QSI“ in order to be considered upon calculation.
generate new Receivers
By activating the option „generate new Receivers“ three options are available:
6
Calculation of Test
Points
•
Grid Points: By clicking the „Calculate“ button the specified number of
receivers will be generated at arbitrary locations. With a calculation area
defined the receiver points will be distributed inside that area, otherwise
within the entire limits.
•
Facade Points: By clicking „Calculate“ the specified number of facade
points (as QSI-receivers) will be generated at arbitrary locations (at a
distance off the facades specified on dialog Building Noise Map). The
generation of facade receivers requires to generate building evaluation
symbols for a reasonable number of buildings in the project (or for all
buildings). Facade receivers will just be generated for buildings having a
building evaluation symbol addressed.
•
Points on Iso-Lines: With this option the approach is different. First,
select on dialog Configuration of Calculation the project configuration
as required and recalculate the grid (via Grid menu). Now, select on dialog QSI-Statistical Analysis the option „Points on Iso-Lines“ and
change - if required - the reference configuration. By clicking „Calculate“
the specified number of receiver will be generated at arbitrary locations
on the iso-line with the specified level. This option requires that a valid
grid exists. The appearance of the grid is not relevant.
This option enables to control whether the reference and/or the project configuration should be considered upon recalculation. In case of evaluation options „Grid Points“ and „Facade Points“ the settings of the project
configuration can be altered directly via the file-selector symbol.
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This box displays the results of the statistical evaluation, as there are:
resulting parameters
abbreviation
0,1-quantile
0,9-quantile
standard deviation of level differences
mean value of level differences
minimum level difference
maximum level difference
q0.1
q0.9
sigma
mean
min
max
Results
The lower table displays the coordinates of the receiver points, the levels for
the reference and then project configuration, and the level differences.
Individual Results
Upon click on the button „--> Word“ both configuration settings, the results
for the statistical parameters, and the individual results will be exported to
MS-Word. The template file QSI_TMPL.RTF supplied with CadnaA (see installation directory) can be edited by the user.
Word-Export
In section „Configuration“ only those parameters are displayed where the
reference and the project configuration differ from each other. At the end of
a QSI-analysis, this enables to check whether the intended settings for both
configurations have been set correctly.
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Example
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6.7.2 QSI - Statistical Analysis
The influence of the projection of line sources on the receiver level shall be
statistically be evaluated for a project with roads and buildings. The receiver
points for QSI-analysis will be generated by CadnaA. In the reference configuration, the projection of line and area sources shall be turned off and the
maximum error shall be set to 1 dB.
Open the QSI-dialog an assign the variant „(default)“ for the reference and
V01 for the project configuration. To check for the default-reference settings
switch to „User defined“ and click the button „Copy default“ to display all
relevant parameters. The project configuration shall comply with this reference configuration, besides the projection for line sources deactivated.
To check and alter the project configuration, click on the file-selector symbol
in the dialog section „Calculation of Test Points“. Ensure that the projection
of line and area sources on tab „Partition“ is deactivated and enter on tab
„General“ a maximum error of 1 dB.
Run the calculation with options „Test Points, generate new Receivers, 20
Grid Points“. The result is displayed below.
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QSI-result after calculation
The exported MS-Word-file indicates that the project configuration differs
from the reference configuration just by the setting of projection of line
sources (template file QSI_TMPL.RTF edited).
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6.8
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QSI - Statistical Analysis
The "Requirements and Testing Conditions for statistical qualification of level differences" stated in DIN 45687 /33/, annex F (available in German only)
are implemented in CadnaA. To statistically evaluate the level differences
from two calculation runs with different configuration settings the 0.1-quantile and the 0.9-quantile are calculated and displayed (10%- resp. 90%-value
of the distribution of the level differences).
The command QSI-Statistical Analysis is available via the menu Tables
|Miscellaneous. The evaluation may be applied to grid points, to facade
points or to points on lines of equal sound level (Iso-Lines).
Dialog QSI - Statistical Analysis
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6.8 QSI - Statistical Analysis
The statistical evaluation in CadnaA considers all active receiver points (minimum number of receivers = 20). The additional requirement according to
annex F of DIN 45687 regarding a minimum horizontal distance of userdefined receivers of 2 m from sources and obstacles has to be ensured by the
user himself. When receivers are generated by CadnaA the minimum
horizontal distance will be respected automatically.
Assignment of
Variants
Specify which of the variants in the project file should be considered as reference configuration and as project configuration. Normally, the setting
„(default“)“ applies for the reference configuration which is defined globally
(see below, Reference Configuration). With the default reference configuration selected, the additional variant „REF“ (corresponding with variant V16)
will be listed on the list boxes „Reference Configuration“ and „Project
Configuration“ after calculation.
Reference
Configuration
As far as the reference configuration is concerned the default values (setting
„Default“) can be applied or be altered by the user (setting „User defined“).
In the latter case the default reference configuration values will be listed in
the box upon click onto the button „Copy Default“. The parameters listed in
the table below are available for the time being..
6
parameter (unit / value range)
variable/default value
maximum error (dB):
search radius (m):
grid interpolation on/off (1/0):
raster factor (-):
projection of line sources on/off (1/0):
projection of area sources /off (1/0):
order of reflection (1-20):
max. distance source-receiver (m):
ibid, interpolate from (m):
reflector-search radius source (m):
reflector-search radius receiver (m):
MAXERROR=0.0
SEARCHRAD=3000
RASTER_INT=0
RASTERFACT=0.5
PROJ_LQ=1
PROJ_FQ=1
REFLORDER=1
REFL_DMAX=3000
REFL_DMAXI=3000
REFL_RAD_S=3000
REFL_RAD_R=3000
The reference configuration settings can be changed by entering different
values for the parameters as required.
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Select the evaluation parameter used for the statistical evaluation. With setting „(current)“ the active performance parameter is used.
Evaluation Parameter
DIN 45687, annex F, requires a minimum number of 20 receivers for the
evaluation.
Test Points
In order to use the existing receivers shall, their ID must be changed to the
text string „QSI“ in order to be considered upon calculation.
use existing Receivers
By activating the option „generate new Receivers“ three options are available:
generate new Receivers
•
Grid Points: By clicking the „Calculate“ button the specified number of
receivers will be generated at arbitrary locations. With a calculation area
defined the receiver points will be distributed inside that area, otherwise
within the entire limits.
•
Facade Points: By clicking „Calculate“ the specified number of facade
points (as QSI-receivers) will be generated at arbitrary locations (at a
distance off the facades specified on dialog Building Noise Map). The
generation of facade receivers requires to generate building evaluation
symbols for a reasonable number of buildings in the project (or for all
buildings). Facade receivers will just be generated for buildings having a
building evaluation symbol addressed.
•
Points on Iso-Lines: With this option the approach is different. First,
select on dialog Configuration of Calculation the project configuration
as required and recalculate the grid (via Grid menu). Now, select on dialog QSI-Statistical Analysis the option „Points on Iso-Lines“ and
change - if required - the reference configuration. By clicking „Calculate“
the specified number of receiver will be generated at arbitrary locations
on the iso-line with the specified level. This option requires that a valid
grid exists. The appearance of the grid is not relevant.
This option enables to control whether the reference and/or the project configuration should be considered upon recalculation. In case of evaluation options „Grid Points“ and „Facade Points“ the settings of the project
configuration can be altered directly via the file-selector symbol.
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Calculation of Test
Points
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Results
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6.8 QSI - Statistical Analysis
This box displays the results of the statistical evaluation, as there are:
resulting parameters
abbreviation
0,1-quantile
0,9-quantile
standard deviation of level differences
mean value of level differences
minimum level difference
maximum level difference
q0.1
q0.9
sigma
mean
min
max
Individual Results
The lower table displays the coordinates of the receiver points, the levels for
the reference and then project configuration, and the level differences.
Word-Export
Upon click on the button „--> Word“ both configuration settings, the results
for the statistical parameters, and the individual results will be exported to
MS-Word. The template file QSI_TMPL.RTF supplied with CadnaA (see installation directory) can be edited by the user.
In section „Configuration“ only those parameters are displayed where the
reference and the project configuration differ from each other. At the end of
a QSI-analysis, this enables to check whether the intended settings for both
configurations have been set correctly.
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6.8 QSI - Statistical Analysis
The influence of the projection of line sources on the receiver level shall be
statistically be evaluated for a project with roads and buildings. The receiver
points for QSI-analysis will be generated by CadnaA. In the reference configuration, the projection of line and area sources shall be turned off and the
maximum error shall be set to 1 dB.
Open the QSI-dialog an assign the variant „(default)“ for the reference and
V01 for the project configuration. To check for the default-reference settings
switch to „User defined“ and click the button „Copy default“ to display all
relevant parameters. The project configuration shall comply with this reference configuration, besides the projection for line sources deactivated.
To check and alter the project configuration, click on the file-selector symbol
in the dialog section „Calculation of Test Points“. Ensure that the projection
of line and area sources on tab „Partition“ is deactivated and enter on tab
„General“ a maximum error of 1 dB.
Run the calculation with options „Test Points, generate new Receivers, 20
Grid Points“. The result is displayed below.
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6
QSI-result after calculation
The exported MS-Word-file indicates that the project configuration differs
from the reference configuration just by the setting of projection of line
sources (template file QSI_TMPL.RTF edited).
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6.9 Batch Operation
6.9
Batch Operation
It is possible with CadnaA to automatically calculate in succession a grid or
individual receiver points. This is especially interesting for long-term
calculations if you, e.g., want to calculate different variants during the
weekend or over-night.
The required steps to set-up the batch processing are explained in the
following.
Change Command
starting CadnaA
•
Activate the CadnaA link on the WINDOWS desktop by clicking it with
the right mouse button.
•
Select the context menu command Properties.
•
Insert into the box „Target“, after the string „cna32.exe“ a single blank
and the following string: /batch=1
Subsequently, the dialog looks like shown on the following page.
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Input box „Target“ extended by „ /batch=1“
CNABATCH IN and
OUT
•

Create a directory CNABATCH on your C-drive. In CNABATCH, create two sub-directories called IN and OUT.
Naming the sub-directories IN and OUT is mandatory!
CNABATCH is the default directory for the batch feature. If you use this
name, no modification of the Cadnaa.ini file is required. (If you wish to use a
different name, see below.)
The paths then are:
C:\CNABATCH\IN
C:\CNABATCH\OUT
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6.9 Batch Operation
•
Copy all those *.CNA files to be processed into the IN directory. It goes
without saying that in each project file the calculation configuration and
the immission point grid must be defined accordingly.
If you do not stick to the default directory name CNABATCH on drive C,
an entry must be made in the file CADNAA.INI residing in the Windows directory (e.g., ...\WINDOWS (for Windows 3.11/95) or ...\WINNT (for
Windows NT) etc.).
•
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Entry in CADNAA.INI if
necessary
Open this file using an editor and insert the path where your two
directories IN and OUT are, in the series of commands following the
header [Main]. If, for example, the directory is WEEKEND instead of
CNABATCH, and WEEKEND itself contains in a directory CADNAA_W, you will have to insert the following line:
6
BatchDir=C:\CADNAA_W\WEEKEND
•
Then save the file and close it.
When CadnaA is launched with the parameter /batch=1 on the expanded
command line, it will check the IN directory for files every 30 seconds. If any
files are found, these will be opened and calculated one by one. The results
will be saved under the same name in the OUT directory, and the files already
calculated are deleted from the IN directory.
Once CadnaA has processed all files, close the program as usual.
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
CadnaA should not be run using the batch mode for normal project
work, but just for batch calculations because in the batch mode the software attempts to open any files in the IN-directory.
In order to save the trouble of having to delete and re-enter the batch
parameters on the command line over and over again, you may wish to create
an additional CadnaA shortcut on the WINDOWS desktop (e.g. by copying)
where the batch parameter is set permanently. For clarity, the new shortcut
might be named, e.g. CadnaA-Batch. Use this shortcut to launch the program for a batch calculation.
6
This enables a highly time-efficient and professional work with CadnaA,
particularly if several PCs are available in a network.
In this context also pay attention to the comprehensive facility of PCSP (Program Controlled Segmented Processing) - (see chapter 6.10).
Processing Order
There need to be distinguished:
•
Order of processing with several CadnaA files in the batch directory IN:
The processing occurs according to the date of the CadnaA file, with the
oldest calculated first, etc.
•
Order of processing of the tiles within a CadnaA file: The individual tiles
are processed according to their order in the table „Section“ (from top
down). The order when last saving the CadnaA file is relevant.

The assigned PART number in the ID of the tiles (PART: xxx) is not
relevant for the processing order.
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6.9 Batch Operation
By the BATCH command it is possible to execute calculations automatically
for grids (noise map) or individual receiver points for several files or to continue a stopped calculation at the point where it has been stopped. The selection of the desired mode is controlled by parameters in text blocks (see
chapter 12.5). If you do not create a text block a grid is calculated automatically.
To define parameters for calculations in the Batch mode create a local text
block named CNABATCH (pay attention to the capital letters). Enter one or
more of the following commands to execute the corresponding calculation:
Parameter
equals
calculation of
CALC_IMM
0
no receiver points (default)
CALC_IMM
1
receiver points (active variant only)
CALC_IMM
2
receiver points (all variants)
CALC_ RASTER
0
no grid
CALC_ RASTER
1
grid (active variant only, default)
CALC_ RASTER
2
grid (all variants)
UPDATE_RASTER
1
continues an interrupted calculation from
break position (equals selecting the
command Grid|Calc Grid while holding
down the SHIFT key)
CALC_MESSAGE
CALC_POLL

Computer1
1
calculation of air pollution with option
APL
CALC_IMM corresponds as well to the individual inserted receivers as
to the building evaluation.
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Local text block CNABATCH
Several Computers
and the Batch
Command
Access to the same folder/directory through several computers is
unambiguously regulated in the Batch mode. If a file is opened, the extension
of this file is renamed from CNA in CNC - another opening of this file is
therefore impossible. After finishing the calculation the extension is again renamed in CNA and saved in the corresponding OUT directory.
Message after finishing the calculation
A message can be displayed by CadnaA when a calculation has terminated.
This requires that a message software (e.g. WinPopUp) is installed to your
computer and that a local text block CALC_MESSAGE has been defined in
the CadnaA file. In this text block, the PC‘s path or the PC‘s name which
should receive the message must be defined.
Partial Levels at
Receivers using
Batch-mode
Partial levels at receivers are generated when using normal batch mode (i.e.
without tiled the project area). Set CALC_IMM=1 (for the active variant) in
the local text block CNABATCH. Calculating this file with batch calculation
will return partial levels at receivers.
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6.10 PCSP - Program Controlled Segmented Processing
6.10
PCSP - Program Controlled Segmented Processing
CadnaA is able to process more than 16 million objects per object type without any problems, even models of cities. Therefore, the limiting file size is
normally given by the PCs RAM. Using PCSP even this limit is irrelevant.
Program controlled segmentation with user-defined partitioning allows you
to load automatically the segments one after another for calculation. Thus the
RAM is able to work without hard disk access.
6
If several CadnaA computers are at your disposal for calculation, e.g. within
a network, they can simultaneously process the same project file. PCSP with
its PCSP-Part-Viewer by CadnaA automatically organizes and manages the
required processes.
In order to specify a directory for the batch-calculation select form the menu
Calculation|PCSP the command Choose Batch-Directory. On the subsequent dialog you may either select an existing directory or generate a new
one. Upon confirmation by OK CadnaA creates the sub-directories IN and
OUT within the selected directory.
Choose BatchDirectory
1.
Generate in your file to be calculated sections used the subdivide the
area into equal sized tiles. This procedure is called "tiling" (see chapter
9.10).
Activating PCSP
2.
Give the