Realization and application of model of unloading rock burst based on PFC3D
LI Sha-sha;CUI Tie-jun;WANG Lai-gui;MA Yun-dong;College of Safety Science and Engineering,Liaoning Technical University;Key Laboratory of Mine Thermodynamic Disasters and Control of Ministry of Education;Tunnel & Underground Structure Engineering Center of Liaoning,Dalian Jiaotong University;School of Mechanics and Engineering,Liaoning Technical University;
In order to study the unloading rock burst inducted by tunnel excavation,and the characteristics of microscopic behavior of the process of rock burst,a rock burst model based on energy theory was built and implemented by PFC3D. According to the relevant literature summary of microscopic process of rock burst,a remaining energy equation was put forward. A method was worked out for calculating rock dissipation energy and rock released elastic energy. The processes of rock burst caused by unloading were simulated under different geological conditions of a certain mine. The results show that at the depth of820 m,the rock burst has the following characteristics: the time of rock burst is a short period,on the macro level,a rock burst is made by superposition of many micro rock bursts,rock burst is accompanied by prominent deformation of unloading surface of rock mass,the prominent deformation of rock mass may cause the collapse of unloading surface,at the depth of 420 m slight rock bursts begin to occur.