Seismic bearing capacity of soils

This paper derives the seismic bearing capacity factors for a C- phi soil within the framework of the Mohr-Coulomb theory. Horizontal and vertical accelerations, and the effects of: a) inertia forces of the soil both below and above the footing; and b) the applied loads are all taken into consideration. The method is used to derive the ultimate seismic bearing capacity for a square footing 2.5m wide founded 1.0m below a homogeneous soil with C (soil cohesion parameter) = 7 kPa, phi = 25 degrees and a unit weight of 18 kN per cubic metre. The results indicate that the horizontal accelerations as well as soil cohesion and vertical accelerations affect the bearing capacity coefficients considerably.