Civil Engineering Reference
In-Depth Information
FIGURE 6.10
Relationship between cyclic resistance ratio and corrected shear wave velocity for clean
sand, silty sand, and sandy silt for
M
7.5 earthquakes. (
From Andrus and Stokoe 2000, reprinted with per-
mission of the American Society of Civil Engineers.
)
Factor of Safety against Liquefaction
6.2
Use the data from the example problem in Sec. 6.4.5, but assume that there is a
vertical surcharge pressure applied at ground surface that equals 20 kPa. Determine the
cyclic stress ratio induced by the design earthquake.
Answer:
CSR
0.31.
6.3
Use the data from the example problem in Sec. 6.4.5, but assume that
a
max
g
0.1
and the sand contains 15 percent nonplastic fines. Calculate the factor of safety against liq-
uefaction.
Answer:
See Table 6.3.
6.4
Use the data from the example problem in Sec. 6.4.5, but assume that
a
max
g
0.2
and the earthquake magnitude
M
5
1
⁄
4
. Calculate the factor of safety against liquefaction.
Answer:
See Table 6.3.
6.5
Use the data from the example problem in Sec. 6.4.5, but assume at a depth of 3 m
that
q
c
3.9 MPa. Calculate the factor of safety against liquefaction.
Answer:
See Table 6.3.
