Civil Engineering Reference
In-Depth Information
FIGURE 7.13
Subsoil profile, road site, Niigata. (
Reproduced from Ishihara 1985.
)
improvement: per Fig. 7.1, 45 cm; per Fig. 7.2, 35 cm. After improvement: per Fig. 7.1, 0.3
cm; and per Fig. 7.2, 2.7 cm.
7.16
Use the data from Prob. 6.12 and Fig. 6.13. Assume that there has been soil
improvement from ground surface to a depth of 15 m, and for the zone of soil having soil
improvement (0 to 15-m depth), the factor of safety against liquefaction is greater than 2.0.
A mat foundation for a heavy building will be constructed such that the bottom of the mat
is at a depth of 1.0 m. The mat foundation is 20 m long and 10 m wide, and according to
the structural engineer, the foundation will impose a net stress of 50 kPa onto the soil (the
50 kPa includes earthquake-related seismic load). Calculate the earthquake-induced settle-
ment of the heavy building, using Figs. 7.1 and 7.2.
Answer:
Per Fig. 7.1, 17 cm; per
Fig. 7.2, 19 cm.
7.17
Use the data from Prob. 6.15 and Fig. 6.15. A sewage disposal tank will be
installed at a depth of 2 to 4 m below ground surface. Assuming the tank is empty at the
