Simulation of the earthquake-induced soil-rock mixed accumulation body sliding movement using discrete–continuous coupled approach.

Soil-rock mixed accumulation bodies produced by rainfall, earthquake or early landslides tend to have unconsolidated structure and poor stability, and are prone to failure under the rainfall or earthquake. The Jiuzhaigou earthquake occurred in China on August 8, 2017, caused a lot of soil-rock mixed accumulation bodies on the slope, which seriously threatened the safety of people's lives and property. Earthquakes occur frequently in this area, so it is very important to analyze the instability and movement characteristics of the soil-rock mixed accumulation bodies under earthquake. In order to overcome the shortcomings of single numerical simulation method in simulating large-scale landslide, the discrete–continuous coupled approach is adopted, in which the discrete and continuous models are established to simulate the bedrock and sliding accumulation body, respectively. The results show that it is suitable for simulating the earthquake-induced accumulation body sliding movement. Under the seismic signal, cracks firstly appear in the back edge of the upper accumulation body, and then, the collapse occurs. The sliding body pushes the lower accumulation body to be unsteady and sliding, and finally, the sliding body accumulates at the foot of the slope. The average velocity and displacement of the rock blocks are greater than that of the soil during the movement. [ABSTRACT FROM AUTHOR]