综放开采上覆巨厚砾岩层变形垮落冲击相似模拟研究  

Similar simulation study on deformation and collapsing impact of overlying hugely-thick conglomerate stratum in longwall top-coal caving

作　　者：翟新献[1] 赵晓凡 郭钊洋 任柱安 ZHAI Xinxian;ZHAO Xiaofan;GUO Zhaoyang;REN Zhu'an(School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;School of Emergency Management and Safety Engineering,North China University of Science and Technology,Tangshan,Hebei 063210,China)

机构地区：[1]河南理工大学能源科学与工程学院,河南焦作454000 [2]华北理工大学应急管理与安全工程学院,河北唐山063210

出　　处：《采矿与安全工程学报》2023年第5期1018-1030,共13页Journal of Mining & Safety Engineering

基　　金：国家自然科学基金项目(52074102)。

摘　　要：巨厚砾岩层的垮落对下伏综放工作面前方的煤岩体造成冲击,甚至诱发冲击地压。论文以耿村煤矿13230综放工作面为工程背景,利用相似模拟试验和理论分析,研究综放开采过程中砾岩层变形移动垮落特征、声发射和震动加速度响应特征等。研究结果表明:综放开采上覆巨厚砾岩离层后处于悬顶状态,当砾岩层底部高倾角采动裂隙向上扩展与上部次生裂隙相互连通且贯穿砾岩层时,砾岩层发生初次垮落;垮落体对下伏综放面煤岩体产生冲击作用。综放工作面超前支承压力具有“单峰”特征;砾岩层初次垮落时超前支承压力的峰值应力集中系数最大;综放工作面后方采空区底板处于低应力区。声发射事件定位反映出砾岩层中主控裂隙的孕育产生、扩展演化以及砾岩层垮落的全过程;砾岩层初次垮落前声发射事件数较多,垮落后声发射事件数显著降低;声发射事件参数即最大幅值、振铃计数和绝对能量均与工作面推进度有关,砾岩层初次垮落前声发射事件参数均达到极值,初次垮落以后声发射事件参数均显著降低;砾岩层初次垮落具有强冲击和瞬时性的特征。研究结论为义马矿区综放开采围岩控制和冲击地压防治提供技术支撑。The collapsing of the extremely-thick conglomerate stratum has an impact on the coal/rock mass in front of the underlying longwall top-coal caving face(LTCF),and even induces rock burst.Based on the engineering background of LTCF 13230 in Gengcun Coal Mine,Yima mining area,China,the paper studies the deformation,movement and collapsing characteristics,acoustic emission and vibration acceleration response characteristics of the conglomerate stratum in the process of longwall top-coal caving mining(LTCM)with similar simulation tests and theoretical analysis.The results show that:the overlying extremely-thick conglomerate stratum in LTCM is in a suspended state after bed sepa-ration.When the high-angle mining-induced fracture at the bottom of the conglomerate stratum expands upward and is connected with the upper secondary fractures and run through the conglomerate stratum,the conglomerate stratum collapses firstly.The collapsing body had an impact on the coal/rock mass of the underlying LTCF.The advancing abutment pressure of LTCF has the characteristics of the single peak;the peak stress concentration factor of advancing abutment pressure is the largest when the conglomerate stratum collapses firstly.The floor of the goaf behind LTCF is in the low stress area.The location of acoustic emission events reflects the whole process of the generation,expansion and evolution of the main control fracture in the conglomerate stratum and the collapsing of the conglomerate stratum.The number of acoustic emission events before the first collapsing of the conglomerate stratum increases,which reduces significantly after the first collapsing.The acoustic emission event parameters,namely the maximum amplitude,ringing count and absolute energy,are all related with the coal face advancement.The parameters of acoustic emission events reach the extreme value before the first collapsing of the conglomerate stratum,which decreases significantly after the first collapsing.The first collapsing of conglomerate stratum has the characteristi

关 键 词：特厚煤层 综放开采 巨厚砾岩层 垮落冲击 超前支承压力 

分 类 号：TD325[矿业工程—矿井建设]