Abstract:The seismic load has an adverse effect on the bearing capacity of the footings. However, few studies are performed to study its impact on the bearing capacity of slopes. In this study, a rigorous analysis in the framework of the upper-bound limit state plasticity, known as the discontinuity layout optimization (DLO), is adopted to investigate the performance of footings placed on the top of slopes considering the horizontal seismic action by the pseudo-static method. A set of design charts containing the horizontal seismic acceleration are presented for preliminary estimates. The results show the differences from the horizontal foundation, c, φ and γ of foundation soil will produce coupling actions for this problem. But in the existing researches, Nc and Nγ are calculated separately and linearly superposed without considering the complexity of slope projects, thus the bearing capacity of c-φ slope is underestimated.
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