Question II $(\%50)$: A circular foundation of diameter $8m$ supports a tank. The base of the foundation is at $1m$ from the ground surface. The vertical load is $20MN.$ The tank foundation was designed for short$-$term loading conditions and ${}_{\text{s}\text{a}\text{t}}=19k\frac{N}{m^3}).$ The groundwater level when the tank was initially designed was at $4m$ below the ground surface. It was assumed that the groundwater level was stable. However, Fourteen months after the tank was constructed and during a week of intense rainfall, the groundwater table reached the base of the circular footing and the tank foundation failed. It was speculated that failure occurred by bearing capacity failure. In light of this information, Please calculate & check short term as well as long term bearing capacity. The friction angle is ${}_p^{\text{'}}=25$ from simple shear tests.