Numerical estimation of landslide-generated waves at Kaiding Slopes, Houziyan Reservoir, China, using a coupled DEM-SPH method

The intrusion of debris avalanches into reservoirs frequently occurs in mountainous regions and is a complex solid-fluid interaction. A coupled discrete element method (DEM) and smooth particle hydrodynamics (SPH) method is developed to forecast the entire process of disaster chains including landslide motion, wave generation, and wave propagation on Kaiding slopes at the Houziyan Reservoir, Sichuan Province, China. The sliding masses are treated as granular assemblies with collisions instead of rigid solid. The simulation results indicate that the maximum velocity of debris avalanches when swarming into the water surface is beyond 30 m/s, and the maximum wave elevation on the watercourse and the maximum run-up wave elevation generated by landslides reach 1867.4 m and 1883.0 m, respectively, and the minimum wave trough is 1822.1 m occurring near opposite bank of landslide. Furthermore, the range of landslide-generated waves is estimated to be approximately a propagation distance of 800.0 m along the axis of the river. The coupled DEM-SPH simulation method provides important inspiration for hazard prevention on reservoir landslides.