Analysis of Seismic Dynamic Response and Failure Mode of Bedding Rock Slopes Based on the DEM-FDM Method

Using the coupled DEM-FDM method, numerical models of bedding rock slopes with different discontinuity distributions were established, and dynamic simulation was conducted focusing on the seismic response and failure mechanism of bedding rock slopes subject to strong earthquakes. The following results are obtained: (1) The acceleration amplification effect is mainly controlled by the slope shoulder terrain, rock mass structure, and elevation of bedding rock slopes. Orthogonal secondary joints that dip-direction parallel to the dip-direction of the bedding plane have a greater impact on the dynamic response of bedding rock slopes than the perpendicular cases. (2) The peaks marginal spectral amplitude at different positions obtained from the Hilbert-Huang transform can effectively identify the internal damage in slopes, which is consistent with the damage and fracture process before sliding. (3) Four models with different rock mass structures show different failure mechanisms, including stable, local cracking, slip tension-cracking and slip-scattering failure. Orthogonal secondary joints that dip-direction parallel to the dip-direction of the bedding plane control the stability of bedding slopes. In conclusion, the coupled method can better reveal seismic dynamic processes of bedding rock slopes, and provides a certain reference for slope engineering in strong earthquake areas.