工作面合理终采线确定及支护技术研究

Study on determination of reasonable terminal line and supportingtechnology of working face

工作面终采线的合理布置对工作面前方大巷或回采巷道的稳定具有重要影响。以23煤柱工作面为工程背景,为保证出煤巷道持续为运煤服务,维护巷道围岩稳定,采用理论分析和数值模拟的方法构建了工作面超前应力分布模型,模拟分析了不同终采线位置应力分布、塑性区发育和围岩变形规律,探究了巷道围岩变形特征和主要影响因素,以此提出了巷道支护优化设计方案。结果表明,理论计算得出工作面最佳终采线位置为距出煤巷道帮部40 m处;模拟得出终采线距出煤巷道超过40 m时,超前煤柱所受压力趋于稳定,塑性区增加幅度微小,围岩变形处于合理范围;提出巷道采用锚索补强和支柱联合支护方案,矿压监测顶板离层量20 mm、左帮变形量最大值158 mm,满足稳定性要求。

The reasonable arrangement of stop mining line in the working face has important influence on on the stability of the main roadway or mining roadway in front of the work face.This article takes the 23 coal pillar working face as the engineering background.In order to ensure the continuous coal transportation service of the coal roadway and maintain the stability of the surrounding rock of the roadway,theoretical analysis and numerical simulation methods are used to construct the advanced stress distribution model of the working face.The stress distribution,plastic zone development,and surrounding rock deformation law at different terminal line positions were simulated and analyzed,and the deformation characteristics and main influencing factors of the surrounding rock of the roadway are explored.Based on this,an optimized design plan for roadway support was proposed.The results show that the optimal terminal line position of the working face is 40 m away from the coal roadway side by theoretical calculation.The simulation results show that when the terminal line is more than 40 m away from the coal roadway,the pressure on the leading coal pillar tends to be stable,the plastic zone increases slightly,and the surrounding rock deformation is in a reasonable range.The combined supporting scheme of anchor cable reinforcement and pillar is proposed in the roadway.The separation amount of roof is 20 mm and the maximum deformation amount of left wall is 158 mm in mine pressure monitoring,which meets the stability requirements.