复杂应力区段煤柱合理留设宽度仿真研究

Simulation study on reasonable width of sectional coal pillar under complex stress

针对南关煤矿3205运输巷道工作面掘进与支护困难、巷道变形严重且维修频繁的现状,为破解复杂应力情况下煤柱合理留设宽度这一关键性问题,借助FLAC 3D软件进行了应力场与位移场仿真分析。研究结果表明:显著的水平应力场、邻近的采动应力场与劣化的围岩稳定性三重因素的综合作用是制约3205运输巷正常掘进作业的瓶颈。在不同煤柱宽度方案比选过程中,窄煤柱在应对较强水平应力与剪切应力作用时处于劣势。煤柱宽度越大,采动应力场对煤柱及工作面的影响越小,采掘活动更为安全。经过方案比选,最终确立留设煤柱在复杂应力区段的合理宽度为30 m。

Considering the current situation of difficult driving and supporting,serious deformation and frequent maintenance in 3205 transport roadway in Nanguan Coal Mine,simulation analysis on the stress field and displacement field was carried out based on FLAC 3D,so as to solve the key problem of reasonable width of coal pillar under complex stress.The results showed that the comprehensive effect of the following three factors,notable horizontal stress field,adjacent mining stress field and deteriorated surrounding rock stability,was the bottleneck restricting the normal driving operation of 3205 transport roadway.Narrow coal pillars were at a disadvantage in dealing with stronger horizontal stress and shear stress in the process of comparing and selecting different coal pillar width schemes.The wider the width of coal pillar was,the smaller the influence of mining stress field on coal pillar and working face was,and the safer the mining activity was.Based on the comprehensive analysis of safety and economy,the width of coal pillar should be set at 30 m.