Failure Mechanism and Bearing Capacity of Rigid Footings Placed on Top of Cohesive Soil Slopes in Spatially Random Soil

This paper focuses on the bearing capacity of vertically loaded rigid footings adjacent to slopes with spatially random soil by performing random adaptive finite-element limit analysis. The solution is illustrated by quantitatively assessing the effect of influential factors, taking into account the spatial variability, soil properties, and geometric parameters on the ultimate bearing capacity and failure mechanism. The variability of the slip surface, which has several failure mechanisms, is investigated for various normalized slope heights, footing distances, slope angles, and spatially variable soil cohesions. Different possibilities of failure mechanisms and sliding surface size resulting from these soil patterns are demonstrated with changes in slope geometry and soil spatial variability. The results quantitatively reveal that a high failure probability with a large variation in bearing capacity is induced by the changes in the failure mechanism and slip surface size.