A long natural slope in an over-consolidated clay (c'=10kPa, φ'=25deg, γsat=20kN/m3) is inclined at 10 degrees to the horizontal. The water table is at the surface and the seepage is parallel to the slope. If a plane slip had developed at a depth of 5m below the surface, determine the factor of safety. Use γwater=10kN/m3.

solve only (D) and (E)

A soil profile consists of 12 m of gravel overlying a clay layer of 3.5 m thickness,which in turn rests on a 4 m sand layer. The dry and saturated unit weights of thegravel are 17.5 kN/m3 and 20.5 kN/m3. Unit weights of the clay and the sand are20 kN/m3 and 19.5 kN/m3 respectively. Below the sand layer lies impermeablebedrock. If a wide excavation of 3 m depth is to be made in a relatively short time,draw the effective, total and pore pressure diagrams before and a long time afterthe excavation is made. Ground water table is 5 m below the ground surface.

A cut is made into a homogeneous soil as depicted in the figure below, at an angle of 60° with the horizontal. Calculate the resisting shear force in kN along the failure plane given that the shear force applied by the overlying soil wedge is 120 kN. The failure plane is at an angle of 40° from the horizontal direction and the ground water level is below this plane. Assume drained conditions for this question.