断层对煤矿冲击地压危险性的影响研究

Study on the Effect of Fault on Rock Burst Potential in Coal Mining

考虑断层不同倾角以及断层的不同力学性质,通过数值模拟研究采动影响下断层活动诱发煤矿冲击地压危险性的机理。结果表明:工作面推进长度、断层倾角和断层不同力学性质对冲击地压的发生有重要的影响:(1)工作面推进长度的增大使得工作面超前支承压力的增大,断层的存在使超前支承压力增加更加明显;(2)断层倾角的增大会使断层面上正应力和切应力的变化波动增强,工作面开采距离的增加会加大断层的相对滑动;(3)断层力学性质增强能够一定程度上降低工作面超前支承压力峰值,断层力学性质降低会阻碍应力的传递,导致冲击地压危险性增强。研究成果能为断层诱发的煤矿冲击地压危险性的评估提供参考。

By considering differentdip angles and different mechanical properties of fault,the effect of fault onrockburst potential in coal mining is studied numerically.The results show that the advancement length of the working face,the inclination of the fault and the mechanical properties of the fault have great influence on the occurrence of rock burst.It is concluded that,(1)the abutment pressure increases with the increase of the advancement length of the working face.The existence of fault makes the peak abutment pressure increase more pronounced.(2)The increase of the dip angle of the fault will increase the fluctuation of the normal stress and the shear stress of the fault plane.The relative slip of fault planes increases with the increase of the advancement length of the working face.(3)The increase of the fault mechanical properties can reduce the peak value of the peak abutment pressure to a certain extent.The decrease of the fault mechanical properties will hinder the transfer of the stress and increase the rock burst risk.The study can provide a reference for the evaluation of the rock burst risk induced by fault in coal mining.