高应力区巷道掘进施工防冲安全技术

Safety Technology for Impact Prevention in Roadway Excavation Construction in High Stress Areas

母杜柴登煤矿巷道向采空区掘进期间片帮明显、冲击风险较大,通过分析向采空区掘进巷道影响因素和矿压显现情况,得到朝采空区掘进不同冲击风险区域:距离采空区50~120 m为中等冲击风险区,0~50 m为强冲击风险区。针对不同等级风险区域制定微震、应力、钻屑综合监测方案与正头直孔卸压、帮部直孔与斜孔相结合卸压方案;在常规卸压工程基础上,在掘锚机后两帮增加施工2~4个10°~50°倾角的斜孔增强卸压。采取相关卸压措施后,巷道帮部高应力向深部转移,帮部片帮减少0.3 m,浅部应力计降低1~2 MPa,冲击风险进一步减低。

During the excavation period of the Mudu Chaideng Coal Mine roadway towards to the goaf,there is significant fragmentation and high impact risk.By analyzing the factors affecting the excavation of the roadway towards to the goaf and the occurrence situation of mine pressure,different impact risk areas are obtained:the distance of 50-120 m from the goaf is a medium impact risk area,and the distance of 0-50 m is a strong impact risk area.Develop a comprehensive monitoring scheme for microseismic,stress,and drilling cuttings in different levels of risk areas,as well as a combined pressure relief scheme for positive head straight holes,side straight holes,and oblique holes;On the basis of conventional pressure relief engineering,2-4 inclined holes with an inclination angle of 10°-50°are added to the two sides behind the anchor excavator to enhance pressure relief.After taking relevant pressure relief measures,the high stress in the side of the roadway transferred to the deep,resulting in a decrease of 0.3 m in the side fragmentation and a decrease of 1-2 MPa in the shallow stress gauge,further reducing the risk of impact.