Research On Fault Activation Pattern Under Multiple Factors’ Infleunces

The existence of the fault caused the discrete and complex state of original stress. when mining working face advanced to the near fault,advanced abutment pressure showed up obvious discreteness with the existence of the fault.Field measurement and numerical simulation showed that it is the discontinuous stress that caused energy and stress accumulation near fault. When the fault activated, and a large amount of energy released in an instant, causing the fault sliding failure, or leading to the imbalance of roof caving and roof caving accident.Different angles of fault also affect the stress distribution near the fault and fault stability, the disturbance to the stress distribution near the fault caused by mining on footwall or heading wall is different, normal fault and reverse fault stress distribution and responding to mining are also different. various factors have different influence degree.The thesis summarizes the common factors which may affect the fault activation rule.Focus on the working face mining, the difference of normal and reverse faults, different mining on heading or footwall,different angles of faults of four factors, this paper analyzes the influences of various factors on the fault activation.Secondly, with the help of simulation software FLAC3D, we simulated the different angles of the fault, normal and reverse faults,heading wall and footwall mining, distances between working face and fault under the comprehensive influences of four factors to explore fault activation rules.Numerical simulation results show that the greater fault angle,the higher the risk of fault activation.The stability of normal fault is less than the reverse fault.The damage to fault stability mining on hanging wall is bigger and the rock deformation mining on footwall is greater.Closer to fault, more dangerous fault activation,the lower fault stability, working face through fault destroy the stability of fault heavily,so we should avoid the working face going through the fault.Mining on heading wall of high angle and normal fault caused the largest damage to the fault.Fault point of view, the order of the influence about the risks of fault activation is fault angle, working arrangement (mining on heading or footwall),fault forms(normal or reverse fault).