柱式采空区矿柱失稳诱导边坡滑塌机制研究  

Study on slope failure mechanism induced by pillar instability above room and pillar goaf

作　　者：陈璐 余茜 罗容 周子龙[3] 曾铃 郭一鹏 CHEN Lu;YU Qian;LUO Rong;ZHOU Zilong;ZENG Ling;GUO Yipeng(School of Civil Engineering,Changsha University of Science&Technology,Changsha 410114,China;School of Resources Environment and Safety Engineering,University of South China,Hengyang 421001,China;School of Resources and Safety Engineering,Central South University,Changsha 410083,China)

机构地区：[1]长沙理工大学土木工程学院,湖南长沙410114 [2]南华大学资源环境与安全工程学院,湖南衡阳421001 [3]中南大学资源与安全工程学院,湖南长沙410083

出　　处：《采矿与岩层控制工程学报》2024年第5期145-160,共16页Journal of Mining and Strata Control Engineering

基　　金：国家自然科学基金资助项目(52334003,52004036,52008038);湖南省自然科学基金优秀青年资助项目(2024JJ4064)。

摘　　要：柱式采空区中矿柱失稳极易诱发地表塌陷、坡体滑移等灾害。本文基于西南矿区典型案例分析,结合物理模型试验和数值模拟等研究,对矿柱逐渐弱化失稳条件下覆岩运移规律、边坡变形破坏特征及失稳滑移机理进行了研究。研究结果表明:矿房开采后,坡体内部应力重分布,采空区边界及矿柱会形成应力集中区,坡脚下方局部采空区顶板垮落。当矿柱劣化导致其不能承受上覆岩层的荷载而失稳时,采空区顶板开始弯曲下沉;在重力作用下,坡内裂缝自采空区边界向上覆岩层扩展,采空区上方形成“坍落拱”;当坡内产生贯通的竖向拉伸裂纹后,裂纹右侧岩体产生倾向坡外的位移,坡脚岩体受其上覆岩层的压缩及下方采空区顶板剪切变形的共同影响而逐渐破碎,坡体中下部破碎岩体被挤压向外运动,诱导了坡体出现溃屈式滑塌。总体上,矿柱逐渐失稳诱导边坡滑塌过程可分为采空区顶板坍塌阶段、形成贯通裂纹阶段、坡体倾倒失稳阶段和溃屈解体阶段。The surface subsidence or slope slip disasters are easily induced by the collapsing pillar in the room and pillar goaf.In this study,typical instability cases in southwest mining area of China were investigated.The physical and numerical modeling were then carried out.The moving law of overburden rock,the deformation and failure mechanism of slope induced by the gradual weakening and collapse of pillar are studied.The results show that after the mining of the room,the stress of the rock mass was redistributed,stress concentration could be caused at the boundary of the goaf and the pillar.The local collapse of roof occurred at the position below the slope toe.When the pillar was weakening and fails to bear the weight of the overlying rock mass,the roof would start to bend and sink.Under the action of gravity.the cracks expanded from the boundary of the goaf to the overlying rock mass,forming the"collapse arch".When the vertical crack was induced in the slope,the rock mass on the right side of the crack moved outside the slope.The rock mass at the foot of the slope was gradually broken due to the compression of the overlying rock mass and the shear deformation of the roof.The broken rock mass in the middle and lower part of the slope was squeezed outward,which induces the collapse of the slope.Generally,the process of slope collapse induced by the gradual instability of the pillar can be divided into four stages as follow:the collapse stage of the roof rock mass in the goaf,the formation of the penetrating crack stage,the toppling instability stage of the slope and the buckling collapse.

关 键 词：采空区 矿柱弱化 坡体失稳 裂纹演化 

分 类 号：TD32[矿业工程—矿井建设]