Dynamic process simulation of the Xiaogangjian rockslide occurred in shattered mountain based on 3DEC and DFN

Abstract

This study presents the initiation and kinetics characteristics of the Xiaogangjian (XGJ) rockslide failure via three-dimensional (3D) discrete element method (DEM) simulations, particularly taking into consideration of the discrete fracture network (DFN) and rainwater infiltration. The results show that the failure of the locking section of XGJ rockslide caused by high hydrostatic pressure is the major reason that triggers the rockslide. In the process of movement, the maximum velocity is 84.53 m/s and the maximum displacement is 1.81 km. The total movement time of the sliding mass is about 266 s. The movement path of the sliding mass is controlled by the terrain. In addition, the numerical simulation results also show the influence of equivalent internal friction angle and density of joints. Larger equivalent internal friction angle of joints is beneficial to the stability of rock mass and can reduce the depositional range. Larger joint density can make slope failure more obvious. The simulated movement path and depositional area are in good agreement with field investigation. This work provides a new method for the related rockslide research, and contribute a technical note for the comprehensive risk assessment and mitigation in shattered mountains.