Application of Discrete-Element Numerical Simulation for Calculating the Stability of Dangerous Rock Mass: A Case Study

Abstract

An unstable rock mass is a common geological hazard in water conservancy and hydropower engineering in southwest China. The mechanical properties of a rock mass joint and the internal and external physical environment are closely related. In this study, the factors to evaluate the stability of a dangerous rock mass and the geological conditions of a highway slope in Yunnan Province will be evaluated. The block discrete-element method (DEM) will be used to calculate the highway slope of a dangerous rock mass. Moreover, three-dimensional numerical analysis will be performed for the strength reduction of the safety factor. The stabilities of the dangerous rock mass under natural, rainfall conditions, roadbed excavation, and exerted active defending net on dangerous rock mass Nos. 1 and 2 will be determined. The safety coefficients under natural, rainfall, and roadbed excavation conditions are 1.36, 1.27, and 1.36, respectively. When an active protective net was applied onto the surface of dangerous rock mass No. 1, the safety coefficients were 1.39 and 1.31 under natural and rainfall conditions, respectively. When the active protective net was applied onto the surface of dangerous rock mass No. 2, the safety coefficients were 1.43 and 1.35 under natural and rainfall conditions, respectively. The potential instability area of dangerous rock mass No. 1 is the rock mass on the bedding joint face. The potential instability area of dangerous rock mass No. 2 is the local block A. The two dangerous rock masses must be monitored during project operation.