NUMERICAL SIMULATIONS OF EXCAVATION DAMAGE IN DEEP ROADWAYS OF JINCHUAN MINING AREA

Excavation of roadways in deep underground can induce the sharp adjustment of stress,which can undoubtedly cause the damage of surrounding rock. Although the dynamic action of excavation lasts for a short time,the damage caused by excavation provides the basic conditions for subsequent instable failure and disaster phenomena under time-dependent deformation and engineering disturbance. In order to obtain the evolution mechanism of excavation-induced damage in deep roadways and take targeted prevention and control measures in Jinchuan mining area,the equivalent simulation method and heterogeneous model are adopted based on the actual buried depth and rock mass structure types to study excavation damage problems. The simulation results reveal the evolution process and law of excavation damage zone under different levels and rock mass structures. According to the damage and failure law of roadways in the study area,this paper puts forward five evolution models of excavation damage in deep roadways,and reveals the inducing conditions,performance characteristics,mechanical mechanisms and development trends. Relevant understanding and conclusion are expected to provide certain reference for theory and engineering practice.