采动影响巷道弱胶结层状底板稳定性分析与控制对策  

Stability analysis and control strategy of weakly cemented layered floor in mining affected roadway

作　　者：杨仁树[1,2] 朱晔 李永亮[3] 李炜煜[1] 肖博[1] YANG Renshu;ZHU Ye;LI Yongliang;LI Weiyu;XIAO Bo(School of Mechanics and Civil Engineering,China University of Mining & Technology (Beijing),Beijing 100083,China;Civil and Resource Engineering School,University of Science & Technology Beijing,Beijing 100083,China;School of Energy and Mining Engineering,China University of Mining & Technology (Beijing),Beijing 100083,China)

机构地区：[1]中国矿业大学(北京)力学与建筑工程学院,北京100083 [2]北京科技大学土木与资源工程学院,北京100083 [3]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《煤炭学报》2020年第7期2667-2680,共14页Journal of China Coal Society

基　　金：国家自然科学基金青年基金资助项目(51804310);国家自然科学基金资助项目(51134025)。

摘　　要：针对弱胶结层状底板巷道在强烈采动影响下的非对称性变形失稳问题,以梅花井矿工作面辅助运输巷为工程背景,综合采用现场调研、理论计算、数值分析和工程试验的方法,对巷道围岩变形破坏机制和控制对策展开研究。结果表明:井田内含煤岩系成岩程度低,胶结程度差,顶底板岩层层理发育,巷道围岩具有产生大变形的倾向。在采动影响下,巷道呈显著的非对称性变形破坏,实体煤侧肩角、煤柱侧底角和底板是大变形频发区域,巷道收敛以底臌为主;由于工作面位置的动态性和弱胶结软岩的蠕变性,巷道底臌具有典型的时空特性。基于弹性理论,建立采动影响下横观各向同性底板力学分析模型,推导获得层状底板任一点的真实应力状态,准确反映了层状底板非对称应力分布特征。根据摩尔-库伦准则,获得层状底板破坏判据,采用Matlab计算得到底板非对称马鞍形破坏形态。上覆岩层关键岩块回转变形所产生的偏载效应使围岩主应力方向发生偏转,主应力偏角越大,塑性区非对称性扩展越显著,围岩破坏具有显著的方向性,垂直于最大主应力方向围岩破坏程度更大。针对强采动弱胶结层状底板非对称破坏特征,提出基于破碎区修复、塑性区加固、弹性区承载的底板分区差异化支护技术。工程实践表明,支护系统很好的适应了围岩非对称应力环境,围岩变形得到有效控制。In order to overcome the problem of asymmetry deformation and instability of the weakly cemented layered floor roadway under the influence of strong mining effect,the site investigation,theoretical calculation,numerical analysis,and engineering test methods are comprehensively adopted.Taking the auxiliary haulage roadway of the working face in the Meihuajing Coal Mine in China as the engineering background,the deformation and failure mechanism of roadway surrounding rock and the control measures are studied.The results show that the coal-bearing rock series in the mine field have low diagenesis degree,poor cementation degree,and well-developed bedding in the roof and floor strata.Therefore,the roadway surrounding rock has a tendency to produce large deformation.Under the mining influence,the roadway exhibits significant asymmetric deformation and failure.The shoulder corner on the solid coal side,the bottom corner and floor on the coal pillar side are concentrated areas with large deformation,and the roadway convergence is mainly manifested by the floor heave.Due to the dynamics of the position of the working face and the creep of the weakly cemented soft rocks,the floor heave has typical time and space characteristics.Based on the elastic theory,a transverse isotropic floor mechanical analysis model under the influence of mining is established,and the true stress state at any point of the layered floor is derived,which accurately reflects the asymmetric stress distribution characteristics of the layered floor.According to the Mohr-Coulomb criterion,the failure criterion of the layered floor is obtained,and the asymmetric saddle-shaped failure form of the floor is calculated by Matlab.The eccentric loading effect caused by the rotation of the key rock blocks in the overburden layer deflects the direction of the principal stress of the roadway surrounding rock.The larger the deflection angle of the principal stress,the more significant the asymmetry expansion of the plastic zone.Surrounding rock failure has signif

关 键 词：弱胶结 层状底板 采动影响 非对称 差异化支护 

分 类 号：TD353[矿业工程—矿井建设]