高地压巷道动力显现区域围岩稳定性的钻孔窥视分析及对策

Analysis and countermeasures of the peepholes for surrounding rock stability in high earth pressure roadway

针对高地压作用下小庄煤矿40204运输巷在工作面超前区域的动力显现问题,采用钻孔电视成像仪对该区域内8个巷道断面进行了钻孔窥视探测,研究裂隙在顶板、煤柱帮和实体煤帮内的发育程度及分布规律,进而分析该区域巷道围岩的稳定性。根据研究结果,采取加强支护及煤体卸压措施,降低围岩局部应力集中,保持支护结构完整。研究表明,工作面超前60 m范围内围岩裂隙较为发育,支护损伤较大,稳定性较低。在工作面超前区域内,区段煤柱帮的裂隙比实体煤帮更为发育,稳定性相对较低;工作面超前区域顶板离层较为严重,需要加强顶板支护强度,以保障巷道顶板的稳定性。依据钻孔窥视结果,采用锚索配合槽钢补强支护及煤体爆破卸压措施;经过钻屑法检验,上述措施有效降低了巷道冲击危险性。

Aiming at problem that frequent dynamic phenomena of 40204 transport roadway in Xiaozhuang coal mine in advance area under high earth pressure,intelligent borehole television imager was used to detect boreholes eight tunnel sections in this area,and the development degree and distribution law of cracks in roof,pillar and solid coal walls were studied,and then analyzed stability of surrounding rock in this area.According to the research results,strengthening support and coal pressure relief measures were taken to reduce the local stress concentration of surrounding rock and maintain the integrity of support structure.The research showed that under influence of mining disturbance and superposition of the advance abutment pressure,roof separation layer near the working face was more serious,and crack of coal pillar and side was more developed and the stability was lower in the range of 60 m in front of the working face.According to the result of borehole peeping,reinforcement and support with anchor cable and channel steel and pressure relief measures for coal blasting.Through the test of drilling cuttings method,the above measures effectively reduce the impact risk of the roadway.