深埋留巷矿压的煤柱尺度特征数值模拟分析

Simulation Analysis of Retained Roadway Mining Pressure with Coal Pillar Effect in Deep Colliery

摘要: 为解决长沁矿区稀缺煤炭资源区段煤柱设计及留巷强烈动压难题，通过数值模拟计算探讨了4种不同煤柱宽度下，经受两次回采动压的留巷变形破坏及围岩压力分布规律。研究表明，5 m煤柱时所受采动影响最大，留巷超前高应力主要作用在实体煤侧，留巷断面回缩率超过45%，且一次采动后煤柱已完全屈服。8 m煤柱所受采动影响有所减弱，且采动应力分布发生突变，留巷超前高应力转移到上采空区残留煤柱侧，这有利于留巷围岩控制；留巷变形显著降低，最大降幅40%。15 m、25 m煤柱矿压分布规律不同于以上小煤柱，支承压力曲线由单峰值抛物线型向双峰值马鞍型转变，煤柱安全稳定性增大，但资源浪费明显。通过结果对比提出了8~15 m窄煤柱留巷试验的可行性。

Abstract: In order to solve the coal pillar design of scarce resource in Changqin coal mining area and strong dynamic pressure problem of retaining roadway, through the numerical simulation containing four different coal pillar width, the retained roadway which has experienced twice mining damage and deformation with pressure distribution law of its surrounding rock are discussed. The results show that, 5 m coal pillar is affected worst by mining, high stress ahead of retaining roadway mainly act on the solid coal side, leaving lane section shrinkage rate of more than 45%, and after the first mining coal pillar has completely yield. 8 m coal pillar affected by mining is weakened, and the mining stress distribution mutates, ahead high stress of retained roadway transfers to the upper goaf residual coal pillar side, which is conducive to control the surrounding rock deformation. Retained roadway deformation was significantly reduced, with the largest decline in 40%. The distribution law of 15 m and 25 m coal pillar is different from that of the narrow coal pillar, and the bearing pressure curve is changed from parabolic type of single peak value to the saddle type of double peak value, and the safety and stability of coal pillar increases; however, the resource is obviously wasted. Based on the results comparison, the retaining test feasibility of 8 m to 15 m narrow coal pillar is put forward.