A hospital is built in an earthquake-prone region. To mitigate the liq-
uefaction hazard, dynamic compaction is performed that also improves
the soil. Then the CPT is conducted to evaluate the mitigation effort.
The peak ground horizontal acceleration is 0.35 g and the design earth-
quake magnitude is 8.0. The design depth of the hospital’s foundation
is at 6 m; at this depth, the cone penetration resistance at the tip is
11 MPa and the sleeve resistance is measured to be 200 kPa. Assume
the groundwater table is at the ground surface, and saturated unit
weight is 19.6 kN/m³. Calculate the factor of safety against liquefac-
tion.