The spatial position relationship of fault and the strike of longwall face influences on rock burst danger during mining, thus, the abutment pressure was simulated to investigate the rock burst danger affected by skew fault, when the longwall face was advanced to the fault footwall. The discrete element numerical model was built to analysis the stress status based on the mining and geological conditions of No 6304longwall face in Shandong. The simulation results show that, due to the roof strata cut by the skew fault, the triangular coal pillar, comprised of fault interface, the longwall face and the vertical strike face of the tunnel, was formed, and the abutment pressure increases due to the roof sliding along the fault interface. The abutment pressure cannot be transferred to the front coal seam of the longwall face by the reason of the existing of the fault, therefore, the major of the pressure was loaded to the triangular coal pillar which is high stress zone, and the coal seam is extremely liable to burst under this situation. Consequently, while the direction of the face advancing is under the fault footwall and points to the skew fault interface, the triangular coal pillar formed will be loaded with bigger additional stress, and then burst would be induced. The results can provide theoretical references to bursting tendency assessment prior to mining.
The activation of fault, which is an important factor to induce rockburst, have a significant effect on rockburst. Residual stress and stress concentration in fault are difficult to be measured by conventional methods. The division of mining dynamic hazardous areas near a fault by numerical methods was presented by Wang et al. (2007); The risk of rockburst on fault caused by mining was studied by using finite difference method by Li et al. (2010); Theoretical and experimental study on fault rockburst was made by Pan et al. (1998); Transient process of fault rockburst was investigated by Song et al. (2011). It is necessary to make an analysis on the influences of mining near fault, and different risk degree of areas around the fault. In this paper, study by numerical methods on the law of rockburst induced by mining of working face vicinity to an oblique fault during.