弱黏结复合顶板回采巷道围岩变形与加固技术

Surrounding Rock Deformation and Reinforcement Technology of Weak Bonding Compound Roof in Mining Roadway

针对色连二矿12205工作面回采时辅助运输巷围岩变形破坏严重的问题,从巷道围岩岩性、应力变化、水的弱化作用及原支护结构失稳4个方面分析了巷道围岩失稳的原因,提出了回采巷道加固支护方案,应用FLAC^(3D)数值模拟软件对原支护方案与加固方案进行对比分析。结果表明:工作面回采前加补顶板锚索与增打两帮走向锚索,巷道围岩中垂直应力峰值位置向巷道边缘移动了0.9 m,巷道顶底板与两帮移近量分别降低了274 mm与240 mm,巷道围岩的塑性破坏区范围最小。现场实践表明:工作面回采影响期间,辅助运输巷采用加固支护方案后,顶底板及两帮累计移近量比未加固段平均降低了约50%,该巷道加固支护方案取得预期的效果。

For the serious deformation and failure problems of auxiliary transport gateway surrounding rock of 12205 working face in Selian No.2 Mine during the mining period, we analyze the reasons of the instability of roadway surrounding rock from the roadway surrounding rock lithology, the stress changes, the weakening effect of water and the original supporting structure instability four aspects. We propose mining roadway reinforcement scheme and use FLAC^3D numerical simulation software to comparatively analyze original support scheme and reinforcing scheme. Simulation results show that the peak stress in the vertical position of roadway surrounding rock moves 0.9 m to roadway edge when the working face adds roof anchor cable and increases two sides anchor cable before mining; the deformation amount of roof and floor and two sides of roadway reduces 274 mm and 240 mm respectively and the plastic zone of surrounding rock of roadway is the minimal. Field practice shows that the accumulative deformation amount of roof and floor and two sides of roadway is lower an average of about 50% than those unreinforced parts after the reinforcement of auxiliary transport gateway during the period of mining influence. The roadway reinforcement scheme achieves the desired effect.