Seismic and Static 3D Stability of Two-stage Slope Considering Joined Influences of Nonlinearity and Dilatancy

Soil strength nonlinearity and dilatancy have significant impacts on the stability of a slope. In the present analysis, a seismic stability analysis of a three-dimensional two-stage slope considering the joined influences of soil strength nonlinearity and dilatancy is conducted. Based on the limit analysis method, the external work rates by soil weight and the seismic forces as well as the internal energy dissipations are calculated and thereafter the critical height of the slope is derived. In virtue of the nonlinear optimization procedure, the stability factor of a 3D slope subjected to seismic forces is captured. The effects of slope geometry, seismic forces, soil strength nonlinearity and dilatancy on the slope stability are investigated by parameter analysis. It is found from the results that, the depth coefficient α 1 and dilative parameter n have positive effects on the stability of a two-stage slope while the other factors such as the seismic coefficient k h and the nonlinear coefficient m have negative effects on it. In addition, the effect of soil nonlinearity on slope stability aggravates when the seismic force coefficient k h and the dilative parameter n increase.