Numerical Simulation Study on Influence of Faults on Mining Stress

To study the controlling effect of faults on the evolution of mining stress and the characteristics of slip occurrence, an interface element with a Coulomb shear model was used to simulate the interface at the fault by using FLAC^3D numerical simulation software and the processes of face mining along fault trend and fault dip were simulated respectively. The development of normal stress and shear stress as well as slip risk at the fault was studied. Simulation results showed that: the development of normal stress and shear stress at the fault has obvious spatial-temporal features and the sensitivity of shear stress on the fault surface is stronger than the normal stress. Fault above mining layer activates sooner than fault below mining layer when face advances along the fault trend or fault dip. Fault near the upper side of mining layer activates easiest when the distance of mined-out area and fault is 20 m and the slip risk of fault near the below of mining layer is highest when the distance of mined-out area and fault is less 10 m. By contrast with face advancing along the fault trend, mining disturbance makes a larger effect on fault near mining layer when face advances along the fault dip.