强冲击特厚煤层地面压裂覆岩运动规律  

Movement law of overlying rock during surface fracturing in strong impact and extra thick coal seams

作　　者：邓辉 DENG Hui(Shaanxi Binchang Mining Co.,Ltd.,Xianyang 713600,China)

机构地区：[1]陕西彬长矿业集团有限公司,陕西咸阳713600

出　　处：《陕西煤炭》2024年第6期5-10,共6页Shaanxi Coal

摘　　要：坚硬覆岩运动是诱发冲击地压的关键因素之一。为揭示覆岩运动对工作面冲击的孕育致灾过程及诱冲机理,以孟村煤矿401102工作面为工程背景,采用理论分析的方法研究了覆岩空间结构演化特征。针对高位覆岩坚硬顶板实施地面L型水平井分段水力压裂技术,结合理论分析以及现场监测的方法,分析了压裂后采场覆岩运动时空演化规律。结果表明,地面压裂弱化区域硬厚复合砂岩层得到充分弱化,高能微震事件大幅降低;而地面压裂盲区硬厚复合砂岩层形成悬顶结构,弹性能没有得到提前释放,导致工作面开采至下方时会诱发岩层的突然断裂与运动,形成高能微震事件并释放巨大的微震能量。The movement of hard overlying strata is one of the key factors inducing rock burst.In order to reveal the disaster process and induced mechanism of impact of overlying strata movement on the working face,this paper taking the 401102 working face of Mengcun Coal Mine as the engineering background,uses theoretical analysis methods to study the spatial structure evolution characteristics of overlying strata,and implements surface L-shaped horizontal well segmented hydraulic fracturing technology for the hard roof of high overlying strata.Combined with theoretical analysis and on-site monitoring methods,the spatiotemporal evolution law of overlying rock movement in the mining area after fracturing is analyzed.The results show that the hard and thick composite sandstone layer in the surface fracturing weakened area is fully weakened,and high-energy microseismic events are significantly reduced.The hard and thick composite sandstone layer in the blind area of surface fracturing forms a suspended structure,and the elastic energy is not released in advance,leading to the sudden fracture and movement of the rock layer when the working face is mined below,thus forming high-energy microseismic events and releasing huge microseismic energy.

关 键 词：冲击地压 特厚煤层 覆岩运动 地面压裂 微震监测 

分 类 号：TD325[矿业工程—矿井建设]