Analysis of ground movements induced by diaphragm wall installation

21st Alert Workshop Program
Aussois, October the 6th 2010
Analysis of ground movements induced
by diaphragm wall installation
Benoit Garitte, Marcos Arroyo and Antonio Gens
Universitat Politècnica de Catalunya, Barcelona
asientos (mm)
Settlements
[mm]
30-10-06
30-9-06
58
12
10
8
6
4
2
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-30
-32
-34
-36
-38
-40
-42
-44
-46
-48
-50
-52
-54
-56
-58
20-8-08
21-7-08
21-6-08
22-5-08
22-4-08
23-3-08
22-2-08
23-1-08
24-12-07
24-11-07
25-10-07
25-9-07
26-8-07
27-7-07
27-6-07
28-5-07
fechas
Execució bigues c. Xuquer
Rebaix de terres
Pas de la Tuneladora
Execució bigues centrals Estació
Jet protecció CC
Jet 3 (1 col/2 dies)
T1B05286R207HT029Z
Pilots protecció
T1B05283R207HT066Z
Jet rampa (Jet 3)
Pantalles front CC (mòdul 76)
T1B05282R289HT066Z
Pantalles-pila (mòduls 92-95)
Pantalles front CC (mòduls 71-75)
Pantalles rampa costat edificis
29-3-07
28-4-07
27-2-07
28-1-07
29-12-06
29-11-06
Pantalla rampa costat CC (mòduls R1-R5)
Motivation
Sant Cosme. Movimientos 1
T1B05294R208HT066Z
Jet 2 (<1 col/dia)
Outline of the presentation
Boundary condition for diaphragm wall: implementation and
validation
San Cosme station and parameter determination
Modelling one panel: sensitivity analysis
Modelling an entire diaphragm wall: comparison with in situ
measurements
Conclusions
Implementation of the boundary condition
Literature review (Ng y Yan, 1998;
Gourvenec & Powrie, 1999; Schaffer y
Triantafyllidis, 2006) :
Guide wall construction is not taken
into account
Excavation under bentonite slurry
support is reproduced by retiring the
elements included in the volume of the
panel and applying the hydrostatic
pressure (total stresses and null flux)
Fresh concrete is reproduced by a
“bilinear hydrostatic” boundary condition
Hardening of concrete is reproduced
by replacement of the panel volume by
new elements with hard concrete
parameters. The “bilinear hydrostatic”
boundary condition is desactivated
Installation
Function: protection of
existing structures
Impermeabilization
Stiffening
Implementation of the boundary condition
Excavation under bentonite
slurry
Installation of fresh
concrete
Critical depth
Gourvenec & Powrie, 1999
Implementation of the boundary condition
Validation (2D): comparison between CB and G&P simulation results
CB (bentonita)
G&P (bentonita)
CB (24h después bentonita)
CB (hormigón)
G&P (hormigón)
CB (24h después hormigón)
0
Profundidad
Depth
[mm] [m]
-2
-4
-6
-8
-10
-12
-14
-16
-30
-25
-20
-15
-10
Desplazamientos
[mm]
Displacement [mm]
-5
0
Implementation of the boundary condition
Gourvenec & Powrie, 1999
Displacement [mm]
Depth [mm]
Installation of a panel is a
3D event
Effects due to the
installation of various
panels are not additive
Correct representation of
the earth pressure
coefficient is a key issue
Outline of the presentation
Implementation of the boundary condition in CB and validation
San Cosme station and parameter determination
Modelling one panel: sensitivity analysis
Modelling an entire diaphragm wall and comparison with in
situ measurements
Conclusions
San Cosme station
San Cosme station and parameter determination
Quaternary alluvial
Silty clay
Sand
Clay
Gravels
Parameter determination
DMT (Marchetti Dilatometer)
Parameter determination
2.00
4.00 Id
6.00
8.00
Quaternary alluvial
Silty clay
Sand
DMT01
DMT02
DMT03
DMT04
Clay
a
Aren
Sand
Gravels
Limo
Silt
0.00
0.00
-5.00
-10.00
-15.00
-20.00
-25.00
-30.00
-35.00
-40.00
-45.00
-50.00
Arcill
Clay
Depth [m]
DMT (Marchetti Dilatometer)
Parameter determination
Profundidad
[m]
Depth [mm]
DMT (Marchetti Dilatometer)
Quaternary alluvial
Silty clay
0.00
-5.00
-10.00
-15.00
-20.00
-25.00
-30.00
-35.00
-40.00
-45.00
-50.00
Sand
DMT01 -1
DMT02 -1
Clay
DMT03 -1
DMT04 -1
Ajuste del coefficiente de empuje
Gravels
0.0
0.5
1.0
Horizontal stress index
1.5
K0
2.0
2.5
Earth pressure
coefficient
3.0
K0 =
σ 'h
σ 'v
Parameter determination
Depth [m]
DMT (Marchetti Dilatometer)
Quaternary alluvial
DMT01
DMT02
DMT03
DMT04
0.00
-5.00
-10.00
-15.00
-20.00
-25.00
-30.00
-35.00
-40.00
-45.00
-50.00
Silty clay
Sand
Clay
0
DMT modulus
200
400
600
E [bar]
Oedometer modulus
800
Gravels
1000
λ (CC): 0.06
Parameter determination
Depth [m]
DMT (Marchetti Dilatometer)
0.00
-5.00
-10.00
-15.00
-20.00
-25.00
-30.00
-35.00
-40.00
-45.00
-50.00
0.00
Preconsolidation pressure
Swelling coefficient and friction angle:
Mayne (2008): fitting of DMT and CPTu
tests
Permeability values were determined o
the basis of in situ pump tests (AMPHOS)
1.00
2.00
3.00
OCR
Outline of the presentation
Implementation of the boundary condition in CB and validation
San Cosme station and parameter determination
Modelling one panel: sensitivity analysis
Modelling an entire diaphragm wall and comparison with in
situ measurements
Conclusions
Modelling one panel
25m
50m
Modelling domain for one panel
Modelling one panel
Perfil hidrostático en la
bentonita
[mm][m]
cotaDepth
topográfica
0
Perfil hidrostático en el
hormigón
-5
Perfil en el hormigón
(empírico)
-10
Tensión horizontal (total)
-15
-20
-25
0
100
200
300
tensión [kPa]
Stresses
[kPa]
400
Modelling one panel
Settlement evolution
1
Settlement @
Settlement @
Settlement @
Settlement @
Settlement @
Settlement @
Settlement [mm]
0
-1
2m
3m
4m
5m
10 m
16 m
-2
-3
Hardening of the concrete
-4
Injection of fresh concrete
-5
Excavation under bentonite support
0
10
20
30
40
Di Biagio and Myrvoll, 1973
Time [hrs]
Modelling one panel
Convergence of the panel wall
t [horas] = 0.13 , profundidad panel [m] = 1
t [horas] = 0.26 , profundidad panel [m] = 2
t [horas] = 0.39 , profundidad panel [m] = 3
t [horas] = 0.52 , profundidad panel [m] = 4
t [horas] = 0.65 , profundidad panel [m] = 5
t [horas] = 0.90 , profundidad panel [m] = 7
t [horas] = 1.16 , profundidad panel [m] = 9
t [horas] = 1.42 , profundidad panel [m] = 11
t [horas] = 1.55 , profundidad panel [m] = 12
t [horas] = 1.81 , profundidad panel [m] = 14
t [horas] = 2.06 , profundidad panel [m] = 16
t [horas] = 2.32 , profundidad panel [m] = 18
t [horas] = 2.58 , profundidad panel [m] = 20
t [horas] = 2.84 , profundidad panel [m] = 22
t [horas] = 3.10 , profundidad panel [m] = 24
t [horas] = 3.23 , profundidad panel [m] = 25
t [horas] = 8.23 , antes hormigonado
Justo despues hormigonado
t [horas] = 20.23 , antes fraguado
Justo despues fraguado
t [horas] = 24
t [horas] = 2400
Profundidad
[m]
Depth
Depth [mm]
[mm]
0
-5
-10
-15
-20
-25
-40
-20
0
20
desplazamientos
[mm]
Displacement
[mm]
40
Modelling one panel
Settlements
asientos [mm]
[mm]
Settlement profile
2
t [horas] = 0.13 , profundidad panel [m] = 1
0
t [horas] = 0.39 , profundidad panel [m] = 3
-2
t [horas] = 0.65 , profundidad panel [m] = 5
t [horas] = 0.26 , profundidad panel [m] = 2
t [horas] = 0.52 , profundidad panel [m] = 4
t [horas] = 0.90 , profundidad panel [m] = 7
-4
t [horas] = 1.16 , profundidad panel [m] = 9
t [horas] = 1.42 , profundidad panel [m] = 11
-6
t [horas] = 1.55 , profundidad panel [m] = 12
t [horas] = 1.81 , profundidad panel [m] = 14
-8
t [horas] = 2.06 , profundidad panel [m] = 16
t [horas] = 2.32 , profundidad panel [m] = 18
-10
t [horas] = 2.58 , profundidad panel [m] = 20
t [horas] = 2.84 , profundidad panel [m] = 22
-12
t [horas] = 3.10 , profundidad panel [m] = 24
t [horas] = 3.23 , profundidad panel [m] = 25
-14
t [horas] = 8.23 , antes hormigonado
0
10
20
30
40
Distancia
hasta
la pared
Distance
to wall
[m] [m]
50
Modelling one panel: sensitivity analysis
Case 1: base case
Case 2: bentonite slurry level is 2m below the surface
Case 3: length of the panel is 6m (instead of 3.6m)
Case 4: depth of the panel is 35m (instead of 25m)
Case 5: Critical depth is set to H/5 (instead of H/3)
Case 6: width of the panel is 1m (instead of 1.2m)
Asientos @ 3 m (caso 1)
Asientos @ 3 m (caso 2)
Asientos @ 3 m (caso 3)
Asientos @ 3 m (caso 4)
Asientos @ 3 m (caso 5)
Asientos @ 3.1 m (caso 6)
1
Settlements
[mm]
asientos [mm]
Settlement evolution
0
-1
-2
-3
-4
-5
-6
0
10
20
30
Tiempo
[hrs]
Time
[hrs]
40
Outline of the presentation
Implementation of the boundary condition in CB and validation
San Cosme station and parameter determination
Modelling one panel: sensitivity analysis
Modelling an entire diaphragm wall and comparison with in
situ measurements
Conclusions
asientos (mm)
Settlements
[mm]
Execució bigues c. Xuquer
Jet 3 (1 col/2 dies)
Rebaix de terres
Pas de la Tuneladora
Execució bigues centrals Estació
Jet rampa (Jet 3)
Jet protecció CC
Pilots protecció
Pantalles-pila (mòduls 92-95)
Pantalles front CC (mòdul 76)
Pantalles rampa costat edificis
Pantalles front CC (mòduls 71-75)
20-8-08
21-7-08
21-6-08
22-5-08
22-4-08
23-3-08
22-2-08
23-1-08
24-12-07
24-11-07
25-10-07
25-9-07
26-8-07
27-7-07
p6
27-6-07
p7
28-5-07
p5
28-4-07
p1
29-3-07
R3
p4
27-2-07
p3
28-1-07
R5
p2
29-12-06
R1
29-11-06
R4
30-10-06
30-9-06
R2
12
10
8
6
4
2
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
-22
-24
-26
-28
-30
-32
-34
-36
-38
-40
-42
-44
-46
-48
-50
-52
-54
-56
-58
Pantalla rampa costat CC (mòduls R1-R5)
Modelling an entire diaphragm wall
Jet 2 (<1 col/dia)
Settlements
[mm]
asientos [mm]
Modelling an entire diaphragm wall
1
Prisma 1 :3m desde panel (medidas)
0
Prisma 2 :5.5m desde panel (medidas)
Prisma 3 :13.5m desde panel (medidas)
-1
Prisma 4 :23.5m desde panel (medidas)
-2
Prisma 5 :31m desde panel (medidas)
-3
Prisma 6 :42.5m desde panel (medidas)
-4
Prisma 7 :49.5m desde panel (medidas)
-5
-6
R1
R2
R3
R4
R5
p5
p3
p2
p1
p4
p7
p6
20
23
/0
2/
2/
03
/0
1/
/0
14
07
07
20
07
20
06
20
2/
/1
25
05
15
/1
/1
2/
1/
20
20
06
06
-7
Modelling an entire diaphragm wall
Modelling an entire diaphragm wall
Settlements
[mm]
asientos [mm]
Settlement evolution
1
Asientos @ 3 m debidos a la ejecución de dos panel de 3.6m
0
Asientos @ 3 m debidos a la ejecución de un panel de 6m
-1
-2
-3
-4
-5
-6
0
50
100
Tiempo
Time [horas]
[hrs]
Modelling an entire diaphragm wall
Settlement evolution
1
0
Prisma 1 :3m desde panel (simulación)
Prisma 1 :3m desde panel (medidas)
Settlements
asientos[mm]
[mm]
-1
-2
-3
-4
-5
-6
15
/
11
/
17 200
6
/1
1/
19 200
6
/1
1/
21 200
6
/1
1/
23 200
6
/1
1/
25 200
6
/1
1/
27 200
6
/1
1/
29 200
6
/1
1/
01 200
6
/1
2/
03 200
6
/1
2/
05 200
6
/1
2/
20
06
-7
Di Biagio and Myrvoll, 1973
Modelling an entire diaphragm wall
Settlement evolution
1
Prisma 1 :3m desde panel (simulación)
Settlements
[mm]
asientos [mm]
0
Prisma 1 :3m desde panel (medidas)
-1
-2
-3
-4
-5
-6
20
0
23
/
02
/
20
0
02
/
03
/
01
/
14
/
7
7
7
20
0
6
20
0
25
/
12
/
20
0
12
/
05
/
15
/
11
/
20
0
6
6
-7
Modelling an entire diaphragm wall
Settlement evolution
1
Prisma 2 :5.5m desde panel (simulación)
Prisma 2 :5.5m desde panel (medidas)
0
-0.5
-1
-1.5
-2
-2.5
6
20
0
6
05
/
12
/
20
0
6
03
/
12
/
20
0
6
01
/
12
/
20
0
6
11
/
20
0
29
/
27
/
11
/
20
0
6
6
25
/
11
/
20
0
6
11
/
20
0
23
/
21
/
11
/
20
0
6
11
/
20
0
19
/
11
/
20
0
17
/
11
/
15
/
6
-3
6
Settlements
asientos[mm]
[mm]
0.5
Modelling an entire diaphragm wall
Settlement evolution
asientos [mm]
Settlements
[mm]
1
Prisma 2 :5.5m desde panel (simulación)
0
Prisma 2 :5.5m desde panel (medidas)
-1
-2
-3
-4
7
20
0
7
02
/
23
/
02
/
03
/
01
/
14
/
20
0
7
20
0
6
20
0
12
/
25
/
12
/
05
/
15
/
11
/
20
0
20
0
6
6
-5
Modelling an entire diaphragm wall
Settlement profile
1
Settlements
[mm]
asientos [mm]
0
-1
-2
Simulación (R1-R2) @ 27/11/2006
-3
Simulación (R4) @ 27/11/2006
-4
Medida @ 12/02/2007 (p1)
-5
Medidas @ 12/02/2007 (otros prismas)
-6
-7
0
20
40
60
Distancia ato
la wall
pared[m]
[m]
Distance
80
Concluding remarks
Diaphragm wall installation in soft soils may produce settlement in its
neighbourhood. Numerical models may help to quantify and understand the
problem.
Three settlement phases were distinguished during the installation of a panel:
Settlement during excavation under bentonite support
Heave during injection of concrete
Settlement during hardening of concrete
Design parameters were classified by order of importance:
The length of the panel
The bentonite level during excavation
The width of the panel
The depth of the panel
3D effects were shown to be very important
A good agreement between measured and simulated settlements was achieved
Model limitations: soil-wall interface & concrete hardening
Implementation of the boundary condition
Fresh concrete: Critical depth
Schad et al., 2007
Lion Yard, Cambridge
(Lings et al., 2004)
Hcrit = H/3
Hcrit = H/5
Modelling one panel
Case 1: base case
Case 2: bentonite slurry level is 2m below the surface
Case 3: length of the panel is 6m (instead of 3.6m)
Case 4: depth of the panel is 35m (instead of 25m)
Case 5: Critical depth is set to H/5 (instead of H/3)
Case 6: width of the panel is 1m (instead of 1.2m)
Convergence of the panel wall
0
0
-2
-4
-6
-8
-10
-12
-14
-16
-18
-20
t [horas] = 3.23 (caso 1)
t [horas] = 3.23 (caso 2)
t [horas] = 3.23 (caso 3)
t [horas] = 4.35 (caso 4)
t [horas] = 3.23 (caso 5)
t [horas] = 3.23 (caso 6)
Profundidad
Depth [m][m]
Settlements
asientos [mm][mm]
Settlement profile
-5
t [horas] = 3.23 , profundidad panel [m] = 25 (caso 1)
t [horas] = 3.23 , profundidad panel [m] = 25 (caso 2)
-10
t [horas] = 3.23 , profundidad panel [m] = 25 (caso 3)
t [horas] = 4.35 , profundidad panel [m] = 35 (caso 4)
-15
t [horas] = 3.23 , profundidad panel [m] = 25 (caso 5)
t [horas] = 3.23 , profundidad panel [m] = 25 (caso 6)
-20
-25
0
10
20
30
40
Distancia hasta la pared [m]
Distance to wall [m]
50
-40
-30
-20
-10
Desplazamiento
[mm]
Displacement [mm]
0