Civil Engineering Reference
In-Depth Information
FIGURE 9.31
Shear strength and mobilized shear along the base of each slice for the weakening slope sta-
bility analysis (zero shear strength of the liquefied soil). The SLOPE/W computer program was used to gen-
erate the plot (Geo-Slope 1991).
to adjust the factor of safety against liquefaction for sloping ground. Since Fig. 9.24 only shows
a range in values of
K
for a relative density of 35 percent, experience and judgment will be
required in the selection of the value of
K
for different soil densities and sloping ground con-
ditions.
When the slope stability analysis is performed for flow slides, a total stress analysis could
be performed using the undrained liquefied shear strength from Fig. 9.32. Because the flow
slide analysis is approximate, a conservative approach is to perform an effective stress analy-
sis (Sec. 9.4.3) and assume that the liquefied shear strength is equal to zero (or use
r
u
1.0).
9.5 WEAKENING SLOPE STABILITY—
LIQUEFACTION-INDUCED LATERAL SPREADING
9.5.1 Introduction
Lateral spreading is introduced in Sec. 3.4.5 where, as shown in Figs. 3.27 to 3.30, the prin-
cipal factor in the damage at the Port of Kobe was attributed to liquefaction, which caused
