Discrete element analyses of earthquake-induced landslide

The discrete element method (DEM) has been employed to analyze the Tangjiashan landslide induced by the 2008 Ms 8.0 Wenchuan earthquake. In the DEM model, the layered structure of the slope mass can be obtained by generating each sub-layer separately, with assigned different strength and stiffness properties. The bottom intact rock layer was initially bonded together with the basal failure plane to represent initially intact slope, and the site-recorded seismic shaking wave components are used as base excitations. The numerical results show that the slope mass can maintain a stable state under relatively low seismic shaking motions. As the seismic shaking intensity increases, the fractures/cracks occur and propagate gradually along the basal failure plane. The numerical simulations illustrate clearly the progressive failure and subsequent valley damming of the Tangjiashan landslide, from which some mechanisms of slope motion and deformation, as controlled by the complex layering geometries are presented.