Research on Laws of Fault Coal Pillar Abutment Pressure Evolution When Working Face Moves Along the Normal Fault

Taking the 3101 (east) working face of Chaoyang Mine as the engineering background, FLAC^3D numerical stimulation was used to study the effect of fault pillar on law of mining stress distribution when the working face moves along the normal fault. The results show that the barrier effect of mining stress is remarkable, which leads to the high stress of the fault coal pillar. The stress barrier effect of the hanging wall is weaker than that of foot wall, and under the same fault coal pillar, the fault coal pillar of foot wall is instable than hanging wall. The concentrated area of the high stress on the hanging wall is close to the coal wall, the concentrated area of the high stress on the foot wall is distributed on the fault coal pillar when the fault coal pillar is greater than 40 m, and the maximum stress is transferred to the coal wall when the coal pillar is less than 40 m. Field practice verifies different stress evolution of coal pillar under different fault coal stress conditions when the working face moves along the normal fault. In the field practice, the roadway and working face of maintenance measures should be arranged based on the case dependent analysis with geological and engineering conditions in order to ensure safe and efficient production.