Research on Mechanism of Fault Activation by Fluid-Solid Coupling Effect

In the process of mining, faults are likely to be activated and link to mining-induced fissures to form water channel, which is one important reason that induces many water inrush accidents in coal mines. Therefore, in order to analyze the rock stress and deformation characteristics in influence of mining disturbances, water pressure and crustal stress, a multi-physics coupling model is created by Comsol4.2a in this paper. The research results show as followings: under mining disturbance and water stress affect, the rock stress and displacement is basic to its original state when roadway away from the fault is greater than 380m, but the rock stress and deformation displacement increased significantly at the contact surface of fault and coal seam when coal lane away from the fault is less than 80m, and the stress gradient increased significantly between the fault and the mine roadway. This paper determined the 105m as the "critical distance".