深井软岩回采巷道围岩松动圈监测分析及支护方案设计

Monitoring and Analysis of Surrounding Rock Loose Zone in Deep Well Soft Rock Mining Roadway and Design of Supporting Scheme

巷道开挖后煤岩体的原有应力平衡状态被打破,深井软岩回采巷道同时受到高水平应力与采动应力的共同作用,应力集中产生的破坏极易形成较大范围的松动圈。以文家坡煤矿4105工作面运输巷为工程背景,采用全景摄像技术进行围岩裂隙发育程度及分布规律监测,并结合现场调研结果得出运输巷围岩松动圈的分布规律。研究表明:在回采过程中,两帮松动圈深度最大达3.5 m,顶板中央松动圈深度最大达1.2 m,巷道肩部松动圈深度最大达6.9 m,巷道底角塌孔现象严重,巷道变形破坏模式为典型的蝶形破坏模式。基于4105工作面运输巷围岩松动圈的分布规律,提出了4105运输巷补强方案,现场工业性试验表明该补强方案取得了预期的支护效果。根据上述研究成果,将自然平衡拱理论与现场松动圈演化规律相结合,对4107工作面运输巷支护方案进行了优化设计,目前方案已取得了良好的效果。

After roadway excavation,the original stress balance state of coal and rock mass is broken.The deep soft rock mining roadway is affected by high-level stress and mining stress at the same time.The damage caused by stress concentration is very easy to form a large range of loose circle.Taking the transportation roadway of 4105 working face of wenjiapo coal mine as the engineering background,use panoramic camera technology to monitor the development degree and distribution law of surrounding rock fissures,and obtains the distribution law of surrounding rock loose zone of transportation roadway combined with the field investigation results.The research shows that in the mining process,the maximum depth of the loose circle in the two sides is 3.5 m,the maximum depth of the loose circle in the center of the roof is 1.2 m,and the maximum depth of the loose circle in the shoulder of the roadway is 6.9 m.The hole collapse in the bottom corner of the roadway is serious,and the deformation and failure mode of the roadway is a typical butterfly failure mode.Based on the distribution law of loose zone of surrounding rock of transportation roadway in 4105 working face,a reinforcement scheme of 4105 transportation roadway is proposed.The field industrial test shows that the reinforcement scheme has achieved the expected support effect.According to the above research results,the support scheme of transportation roadway in 4107 working face is optimized by combining the natural balance arch theory with the evolution law of field loose circle.At present,the scheme has achieved good results.