New Failure Mechanism for Evaluating the Static and Seismic Ultimate Bearing Capacity of Strip Footings Adjacent to Slope

The seismic slip line field theory (SLFT) is derived based on the method of characteristic, and the critical slope contour calculated by the SLFT is a convex shape when a high surcharge is imposed on the slope top surface. A simple and robustness failure mechanism is proposed to calculate the static and seismic ultimate bearing capacity of strip footing adjacent to the cohesion-frictional slopes where the critical slope contour shifts from the inside of the slope to the outside of the slope with the increase of the boundary load, and the slope is at the limit state when the critical slope contour is tangent to the slope surface. The influence of slope and footing geometric features, soil parameters, and the seismic load on the bearing capacity is analyzed. The ultimate bearing capacity decreases as the strength parameters decreases, and the slope angle and the seismic coefficient increases. The static and seismic bearing capacity calculated by the proposed method does not require the failure models to be initially assumed, and the results are consistent with those of the other methods.