The initial effective stresses on a saturated soil element at a certain depth in a soil mass are σ'1 5 80 kPa, σ'2 = 40 kPa, and σ'3 = 40 kPa. The groundwater level is below the depth of the soil element. A sudden outward movement of a retaining wall that was retaining the soil resulted in the following changes in stresses: ?σ1 = 0 kPa, ?σ2 (parallel to wall) = -10 kPa, and ?σ3 (normal to wall) = -40 kPa.
(a) Plot the initial stress state and the total stress path in (p, q) space.
(b) Plot the effective stress path assuming that the soil is a linearly elastic material.
(c) Determine the maximum excess pore water pressure.