Study on the fault slip rule and the rockburst mechanism induced by mining the panel through fault

Abstract

When mining near the fault can cause the fault to slip and release energy, resulting in rockburst and posing a significant safety risk to coal mine production. This paper proposes a numerical simulation method, based on FLAC3D numerical simulation, for calculating the dynamic response of fault slip below the impact of mining. The release patterns of energy from fault slip are compared between mining via the fault from the hanging wall and mining via the fault from the footwall. The dynamic response characteristics of coal and rock mass under the disturbance of fault slip induced dynamic loading are revealed. This research suggests that the fault slip seismic moment (M0) of the panel mined via the fault from footwall is substantially higher than from hanging wall. Moreover, the disturbance of the footwall panel mining via the fault leads to a more severe disturbance of the surrounding rock mass, resulting in a higher risk of rockburst. Plastic failure of the rock surrounded in the mining area under the strong dynamic loading of fault slip leads to a significant reduction in peak abutment stress, releasing tremendous energy. When the disturbance caused by fault slip dynamic load is relatively small, the maximum abutment stress increases, and the dynamic load increases the energy storage of surrounding rock. Based on energy theory, an energy criterion for the occurrence of fault slip type rockburst has been proposed. The results suggest that strong fault slip dynamic load has an obvious inducing effect on rockburst, and the stronger the dynamic load and greater static load of the rock, the more the manifestation of rockburst.