1758
Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
Table 3: Geotechnical soil parameters (Different sand soil densities
Fig. 5: Calculated vertical effective stress around the Greater
Cairo metro tunnel after tunnel construction
Soil Parameters
Fill
Silty-
clay
Loose
sand
Medium
Sand
Dense
sand
Very
Dense
Sand
Drained Poisson’s Ratio
V
s
0.4
0.35
0.35
0.30
0.30
0.25
Effective Angle of initial
Friction(
ϕ
)
�
(drained)
25
26
27
32
38
43
Modulus Number(m)
300
350
300
500
800
1000
Exponent Number(n)
0.74
0.6
0.6
0.51
0.5
0.4
Soil density (γ
b
) t/m
3
1.8
1.9
1.8
1.85
1.9
2.0
Coefficient of Lateral
Earth Pressure K
0
0.58
0.57
0.56
0.47
0.38
0.32
Fig. 6: Surface settlement profile obtained by both finite element
analysis and surface displacement equation in loose sand (ground
loss of 3%, D=12.5 m, Z/D=2.5)
Fig. 1: Cross section along the Greater Cairo Metro tunnel Line 2
Fig. 7: Surface settlement profile obtained by finite element
analysis and surface displacement equation in medium sand (ground
loss of 3%, D=12.5 m, Z/D=2.5)
Fig. 2
: 2-D finite element model of the Greater Cairo Metro
Fig. 3: Gaussian curve for transverse settlement trough and ground
loss (After Peck and Schmidt, 1969)
Fig. 8: Surface settlement profile obtained by both finite element
analysis and surface displacement equation in dense sand (ground
loss of 3%, D=12.5 m, Z/D=2.5)
Fig.4: Comparison between measured and calculated surface
settlements due to metro tunnel construction (case history)
Fig. 9: Surface settlement profile obtained by both finite element
analysis and surface displacement equation in very dense sand
(ground loss of 3%, D=12.5 m, Z/D=2.5)
