Mechanical analysis of toppling failure using FDEM: A case study for soft-hard interbedded anti-dip rock slope

Abstract

In recent years, massive interbedded sandstone and slate anti-dip slopes have been discovered in the southwest and northwest regions of China. The distinct mechanical properties of different rock layers make these slopes particularly unique. In this paper, the finite-discrete element method (FDEM) is used to study the toppling failure mechanism of soft-hard interbedded anti-dip rock slopes (SHIADRSs). Firstly, the numerical model of soft-hard interbedded anti-dip rock slope (SHIADRS) is established based on a centrifugal loading test. Then, the stress state, evolution of displacement and cracks, and progress of toppling failure in the SHIADRS are analyzed. Besides, the effect of rock structure, slope angle, dip angle, and rock mechanical properties on the toppling failure of SHIADRS is discussed. The simulation results show that the toppling failure process of SHIADRS can be divided into three stages. The stress distribution in hard rock (HR) is obviously different from that in soft rock (SR) layers. HR layers bear greater bending moments than HR layer during the toppling failure of the soft-hard interbedded anti-dip rock slopes. In addition, the stability of SHIADRS is negatively correlated with the slope angle and the dip angle of rock layer. Compared to the inclination angle of rock layers, the slope angle has a more significant impact on the stability of slopes. The internal friction angle of the rock layer has almost no effect on the toppling failure of SHIADRS.