Numerical investigation of the recent Chenhecun landslide (Gansu, China) using the discrete element method

Abstract

Loess–mudstone landslides are widely distributed in Northwest China. However, the deformation features and kinematic processes of these landslides are still not well understood. The Chenhecun landslide occurred on June 10, 2016, near Chenhe village, Dongxiang County, China. Based on detailed field surveys, Google Earth images, and borehole investigations, a geological profile of the landslide was constructed. Using the two-dimensional discrete element software MatDEM, this work analyses the deformation behaviours and kinetic characteristics of the landslide. In the dynamic analysis, the landslide failure process, velocity, displacement, heat generation, and energy conversion are taken into account. During the whole simulated landslide process, the sliding mass at the rear and bottom edges exhibits lower mobility than at the front and upper edges. The kinetic energy of the landslide dominates in the acceleration stage, and friction is the main source of energy dissipation during the entirety of the landslide movement. A band-like high-heat zone is formed near the sliding belt, and this zone expands forward with sliding. The gravitational potential energy is mainly converted into heat, kinetic energy, and elastic potential energy. In addition, the simulated geometry and accumulation characteristics from the MatDEM are in good agreement with the topographic features of the landslide. This work could provide an important reference for understanding the motion of similar geological hazards in the area.