近距离煤层群切顶留巷覆岩应力及变形响应研究  

Study on strata stress and deformation response of contiguous seams under cutting roof for entry retaining

作　　者：杨红运 刘延保[3] 李勇[2] 潘瑞凯[2] 王辉[2] 曹树刚[2] YANG Hongyun;LIU Yanbao;LI Yong;PAN Ruikai;WANG Hui;CAO Shugang(State Key Laboratory of Mountain Bridge and Tunnel Engineering,Chongqing Jiaotong University,Chongqing 400074,China;State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China)

机构地区：[1]重庆交通大学省部共建山区桥梁及隧道工程国家重点实验室,重庆400074 [2]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044 [3]瓦斯灾害监控与应急技术国家重点实验室,重庆400037

出　　处：《矿业安全与环保》2022年第1期8-13,19,共7页Mining Safety & Environmental Protection

基　　金：国家自然科学基金项目(51904043;52078089;52078090);重庆市技术创新与应用示范(社会民生类)一般项目(cstc2018jscx-msybX0067);重庆市自然科学基金面上项目(cstc2020jcyj-msxmX0570);天地科技创新创业资金项目(2020-TD-MS012)。

摘　　要：为了深入了解近距离煤层群切顶留巷上覆岩层应力及变形演化规律,以白皎煤矿B_(4)煤层、B_(3)煤层、B_(2)煤层切顶成巷巷道2442、2443及2444运输平巷为研究对象,开展了3层煤回采巷道开挖物理试验研究,结果表明:(1)上煤层巷道切顶后,顶板卸压;煤层开挖后,采空区顶板垮落并支撑巷道顶板,顶板增压;煤层继续开挖,覆岩断裂,顶板卸压;巷道顶板应力依次经历卸压、增压及卸压过程,其中,高位顶板应力增加较大,应力较高。(2)中部巷道切顶及煤层开挖后,上覆岩层压力同时向上煤层巷道围岩及本巷道采动破碎压实围岩转移,并在两巷道之间的上覆岩层中形成应力增高区。(3)下煤层巷道切顶及煤层开挖后,巷道围岩破坏严重,无集中应力,受前两次开挖卸压影响较大。(4)上覆岩层沿层理面出现错动变形,同时出现垂直拉伸剪切裂纹,采动影响越大,裂纹扩展程度越大。In order to deeply understand the deformation evolution law of overburden stress of contiguous seams under cutting roof for entry retaining,taking the transportation drift 2442,2443 and 2444 in B_(4) coal seam,B_(3) coal seam and B_(2) coal seam of Baijiao Coal Mine as the research object,the excavation physical test of 3 coal seams was carried out,the results show that:(1)after cutting the roof of roadway in upper coal seam,the roof is relieved;after coal excavation,the goaf roof caves and supports the roadway roof,leading to roof pressurizing;with the further excavation of coal seam,the overburden fractures,the roof pressure is relieved again;the roof stress of roadway goes through the process of pressure relief,pressure increase and pressure relief successively,among which,the stress of upper roof increases greatly and the stress is higher.(2)After cutting the roof of the central roadway and coal seam excavation,the pressure of overburden is transferred to the surrounding rock of the upper coal seam roadway and the subsidence crushed and compacted surrounding rock of the roadway,the stress-concentrated area is formed in the overburden between the two roadways.(3)The surrounding rock is seriously damaged and without concentrated stress after roof cutting of the lower roadway and coal seam excavation,which are greatly affected by the pressure relief of the first two excavations.(4)Dislocation deformation and vertical tensile shear cracks appeares along the roof rock mass,and the greater the subsidence influence,the greater the crack propagation degree.

关 键 词：近距离煤层群 切顶留巷 采动影响 顶板卸压 压力转移 拉伸剪切裂纹 

分 类 号：TD32[矿业工程—矿井建设]