极近距离煤层组重复采动顶底板破坏特征微震监测研究  

Study on Failure Characteristics of Roof and Floor in Repeated Mining of Extremely Close Coal Seam Group by Microseismic Monitoring

作　　者：潘竞俊 周金艳 邵敬民[1] 卢钢 PAN Jingjun;ZHOU Jinyan;SHAO Jingmin;LU Gang(No.10 Mine of Pingdingshan Tian′an Coal Mining Co.,Ltd.,Pingdingshan 467000,China;Hebei Coal Science Research Institute Co.,Ltd.,Xingtai 054000,China;Key Laboratory of Mine Water Disaster Detection and Prevention and Control,National Mine Safety Administration,Xingtai 054000,China;Hebei Province Key Laboratory of Mine Microseismicity,Xingtai 054000,China)

机构地区：[1]平顶山天安煤业股份有限公司十矿,河南平顶山467000 [2]河北煤炭科学研究院有限公司,河北邢台054000 [3]矿井水害探测与防控国家矿山安全监察局重点实验室,河北邢台054000 [4]河北省矿井微震重点实验室,河北邢台054000

出　　处：《煤炭技术》2023年第11期63-67,共5页Coal Technology

摘　　要：为研究极近距离煤层组重复采动过程中顶底板岩层破坏特征,以平煤十矿己17-33200工作面(下分层)回采作为工程背景,采用微震监测、理论计算等方法,分析其上三带发育特征、周期性运动、底板破坏深度等规律。研究结果表明:下分层重复采动覆岩活动呈现出裂隙带向上叠加发育、中及大能量事件减少、来压周期变长、底板破坏深度减小等特点。裂隙带破断向上增大幅度为40%;通过微震事件总频次和近煤层顶板事件频次“双增长”20%~70%判定,己17煤周期来压步距为25.4 m,周期为5~8 d;与单层回采中大能量事件聚集在近煤层不同,下分层回采呈现空间分布散乱,且中、大能量事件占比下降约28.2%~38.4%,说明极近距离上分层回采对于下分层具有卸压降能的作用;己17回采底板破坏带约20 m,比己15减小,但底板事件向工作面两巷外部延展范围约150 m,较单层回采增大50%,需加强工作面两巷附近及外围底板隐伏裂隙防治水工作。In order to study the failure characteristics of the top and bottom strata in the repeated mining process of the very close coal seam group,taking the mining of VI17-33200 working face(lower stratification)in Pingmei No.10 mine as the engineering background,using the methods of microseismic monitoring and theoretical calculation,the development characteristics of the upper three belts,periodic movement and the failure depth of the bottom strata are analyzed.The research results show that the repetitive mining overburden activity in lower strata presents the characteristics the development of fracture zone superposition upward,the reduction of medium and large energy events,the lengthening of pressure cycle,and the reduction of floor failure depth.The height of stratified mining in the lower caving zone is basically the same as that of single-layer mining,and the fracture zone extends upward by 40%,with upward superposition development effect.According to the"double increase"of 20%-70%between the total frequency of microseismic events and the frequency of events near the coal seam roof,the pressing step distance is 25.4 m and the period is 5-8 days.Different from the medium and large energy events gathered in the near coal seam in single layer mining,the lower layer mining presents scattered spatial distribution,and the proportion of medium and large energy events decreases by about 28.2%-38.4%,which indicates that the upper layer mining in very close distance has the effect of pressure and energy reduction on the lower layer.The floor failure zone of VI17 mining face is about 20 m,which is smaller than that of VI15 mining face,but the floor event extends to the outside of the two roadways of the working face by about 150 m,which is about 50%larger than that of the single-layer mining.It is necessary to strengthen the prevention and control of water in the vicinity of the two roadways and the hidden cracks in the surrounding floor.

关 键 词：微震监测 极近距离煤层组 重复采动 周期来压 底板破坏深度 

分 类 号：TD327[矿业工程—矿井建设]