深井综放沿空掘巷围岩变形破坏机制及控制对策

Mechanism of rock deformation and failure and its control technology of roadway driving along next goaf in fully mechanized top coal caving face of deep mines

通过对赵楼煤矿综放沿空掘巷现场调查和变形监测,分析了巷道围岩变形破坏特征,深入揭示了围岩变形破坏机制,认为围岩强度低,地应力高,围岩松动破坏范围大,支护结构及参数不合理,巷道围岩应力环境复杂和断面尺寸大是围岩变形破坏的主要原因。基于强力让压耦合支护和关键部位加强支护的围岩控制原理,提出了顶板锚网带索、纵向钢带+两帮锚网梯索、纵向钢筋梯+窄煤柱帮部锚索加强和喷浆+实体煤帮钻孔卸压的支护对策并进行现场试验。结果表明:掘巷稳定后,巷道围岩控制效果良好;锚杆、锚索受力最大值均在其屈服范围内,并为回采期间留够了充足的余量。研究结果为类似复杂难支护巷道提供了借鉴。

According to field investigation and deformation monitoring of roadway driving along goaf in fully mechanized top coal caving face in Zhaolou mine, failure characteristics of roadway surround-ing rock have been analyzed and its deformation failure mechanism has been deeply revealed. Results indicates that low surrounding rock density, high in-situ stress, large destruction scope, unreasonable supporting structure and parameters, complex stress environment and large section size are the main reasons of surrounding rock failure and deformation. Based on control principle of intensive-yielding-coupling support and key parts reinforced support, supporting measures of roof bolt net strip cable, lon-gitudinal strip＋two sides anchor net ladder cable, longitudinal steel ladder＋narrow coal pillar cable reinforcement and gunite＋entity coal side drilling to relief stress are proposed. In addition, field test has been implemented. After roadway driving along next goaf stability, the effect of roadway surround-ing rock is good. The maximum force of bolts and anchors are within their yield range, and set aside a sufficient margin for the recovery period. The results can provide a reference for similar complex and difficult supporting roadway.