Three-dimensional soil slope dynamic stability assessment using minimum potential energy approach

This study introduces a new stability analysis method of 3D slopes under the earthquake forces by combining the minimum potential energy method with pseudo-dynamic method. A new formulation for 3D slope stability analysis is given by introducing the elastic module and Poisson ratio. The minimum potential energy approach is used to directly obtain the stress state on failure surface, and the displacement direction where the potential energy of slope reaches the minimum is regarded as the movement direction of landslide mass. The determination of critical failure surface under earthquake forces and the associated safety factor (SF) are resolved using the genetic algorithm. The performance of the developed approach for evaluating slope stability is demonstrated with four cases. The influences of seismic forces and Poisson ratio on the slope stability are investigated, and the results show that Poisson ratio is insensitive to the accuracy of the proposed method, while the horizontal earthquake force has a greater impact on slope stability than the vertical earthquake force. The effects of the earthquake forces on the normal stress on failure surface, the sliding direction of landslide mass and the shape of failure surface are also explored. In addition, we discuss the differences between the proposed method and the pseudo-static method.