近断层石门揭煤围岩控制技术研究

Study on surrounding rock control technology of near-fault cross-cut coal uncovering

为研究断层影响下巷道围岩应力的演化规律,以近断层石门揭煤为研究背景,利用数值模拟手段对巷道围岩变形破坏进行分析,并提出了巷帮钻孔卸压技术措施。结果表明:受断层活化的影响,石门在揭煤过程中靠近断层的帮部应力集中程度高,垂直应力达到44 MPa;最佳卸压钻孔布置方案为钻孔直径300 mm、钻孔长度5 m和钻孔间距600 mm,该方案下原应力峰值区应力由44 MPa降低到28.64 MPa,应力释放率可达到35%,巷道围岩控制效果显著。该研究为断层构造下巷道围岩控制提供了一种新思路,可有效防治煤矿断层错动型冲击地压灾害。

This paper is an effort to investigate the evolution law behind the surrounding rock stress of the roadway affected by faults.The study taking the near-fault cross-cut coal uncovering as the research background involves analyzing the deformation and failure of surrounding rock of roadway by numerical simulation method;and proposes the the borehole destressing technique measures in roadway side.The results show that influenced by the fault activation,the stress concentration degree of the side of the cross-cut near the fault is high in the process of uncovering coal,and the vertical stress reaches 44 MPa.The pressure relief borehole scheme is the best with the borehole diameter of 300 mm,borehole length of 5 m and borehole spacing of 600 mm.Based on this scheme,the stress in original stress peak area is reduced from 44 MPa to 28.64 MPa,and the stress release rate can reach 35%,suggesting that the control effect of roadway surrounding rock is remarkable.This study provides a new idea of the control of roadway surrounding rock under fault structure,which can effectively prevent and control the rock burst disaster caused by fault dislocation in coal mine.