Civil Engineering Reference
In-Depth Information
FIGURE 6.15
Subsoil profile, sewage site, Niigata. (
Reproduced from Ishihara
1985.
)
conditions are a peak ground acceleration
a
max
of 0.40
g
and moment magnitude
M
w
of 8.5.
Determine the factor of safety against liquefaction for the before-improvement and after-
improvement conditions. Was the improvement process effective in reducing the potential
for liquefaction at the warehouse site?
Answer:
See App. E for the solution and Fig. 6.17
for a plot of the factor of safety against liquefaction versus depth. Since the after improve-
ment factor of safety against liquefaction exceeds 1.0 for the design earthquake, the
improvement process was effective in eliminating liquefaction potential at the site.
