切近位关键层卸压沿空掘巷关键参数与工程应用  

Key parameters and engineering application of roof cutting and pressure relief driving in cutting lower key stratum

作　　者：许磊[1,2] 李明伟 郭亮 肖同强[4] 刘洪林 DAVIDE Elmo XU Lei;LI Mingwei;GUO Liang;XIAO Tongqiang;LIU Honglin;DAVIDE Elmo(School of Civil Engineering,Hennan Polytechnic University,Jiaozuo,Henan 454000,China;Henan Key Laboratory of Underground Engineering and Disaster Prevention,Henan Polytechnic University,Jiaozuo,Henan 454000,China;Shaanxi Times Energy Chemical Co Ltd,Yulin,Shaanxi719000,China;School of Energy Science and Engineering,Henan Polytechnic University,Jiaozuo,Henan 454000,China;College of Geology and Mines Engineering,Xinjiang University,Urumqi,Xinjiang 830046,China;The Norman B.Keevil Institute of Mining Engineering,University of British Columbia,Vancouver V6T 1Z4,Canada)

机构地区：[1]河南理工大学土木工程学院,河南焦作454000 [2]河南理工大学河南省地下工程与灾变防控重点实验室,河南焦作454000 [3]陕西时代能源化工有限公司,陕西榆林719000 [4]河南理工大学能源科学与工程学院,河南焦作454000 [5]新疆大学地质与矿业工程学院,新疆乌鲁木齐830046 [6]英属哥伦比亚大学NBK矿业工程学院,加拿大温哥华V6T 1Z4

出　　处：《采矿与安全工程学报》2023年第1期91-100,共10页Journal of Mining & Safety Engineering

基　　金：河南省国际科技合作培育项目;国家自然科学基金项目(51964043);河南省重点研发与推广专项项目(科技攻关222102320143);河南省地下工程与灾变防控重点实验室(河南理工大学)自主课题;科技厅指导类项目(河南省科技攻关计划、社会发展领域)(172102310705)。

摘　　要：以马家岩煤矿40103回风巷(沿空掘巷)为背景,采用理论分析、数值模拟和工程实践等方法研究切顶卸压沿空掘巷关键参数等问题。结果表明:关键层位于4~8倍采高范围时为近位关键层,位于4~8倍采高范围外时为远位关键层;掘进期间在块体A(悬臂结构)下完成;切角垂直于顶板时卸压效果最好,有利于岩块C_(i)的滑落,但倒梯形切顶结构更有利于超前巷道顶板稳定,选取75°为切顶角度;切顶长度越深卸压效果越好,超过关键层后,再增加切长,支承压力继续降低但降低幅度逐渐减小。通过对比切顶(切长20 m,角度75°)与不切顶条件下不同煤柱宽度支承压力,可发现:实体煤侧支承压力依然呈“单峰”状分布,大煤柱(>10 m)上支承压力呈非对称“马鞍”状分布,小煤柱(<10 m)支承压力呈“钟形”分布,切顶可降低支承压力峰值,但不改变其位置。炮孔间距不大于爆破裂隙损伤半径的2倍,可根据现场及时调整。最终确定护巷煤柱宽度8 m,切顶长度20 m,角度75°,炮孔间距1.0 m,支护方案为锚杆+金属网+钢带+锚索补强联合支护。掘进期间两帮相对位移量156 mm,顶板下沉量186 mm,底鼓量101 mm;10 d左右实现自稳;回采期间两帮相对最大移近速度42 mm/d,顶板最大下沉速度47 mm/d,底鼓最大速度63 mm/d。Based on No.40103 return air roadway of Majiayan Coal Mine,theoretical analysis,numerical simulation and engineering practice and other methods were used to study the key parameters of gob-side entry driving with roof cutting method.The results have shown:it was lower key stratum when the key strata was located in the range of 4 to 8 times of mining height,,when it was above this range,it was far key stratum.Roadway driving along goaf during the excavation period was completed under the block A(cantilever structure).When the cutting angle was perpendicular to the roof,the pressure relief effect was the best,which was also conducive to the sliding of rock mass“C_(i)”.However,considering the inverted trapezoidal roof cutting structure was more conducive to the stability of advanced roadway roof,75°was selected as the roof cutting angle.The deeper the roof cutting length,the better the pressure relief effect could be.When the roof cutting length exceeded the key stratum,the abutment pressure of coal pillar continued to decrease with the increase of the roof cutting length,but the decrease amplitude gradually decreased.By comparing the abutment pressure of different coal pillar widths under the condition of roof cutting(cutting length was 20 m,angle was 75°)and no roof cutting,the following results were found:The abutment pressure on the solid coal side still presented the shape of“single peak”,while the shape of asymmetric“saddle”was presented on large coal pillars(>10 m)and the shape of“bell”was presented on narrow coal pillars(<10 m).Roof cutting reduced the peak value of abutment pressure,but it did not change its position.The blast hole spacing was no more than 2 times of the blasting crack damage radius,and should be adjusted according to site conditions.Finally,the width of protection coal pillar was 8 m,the length of roof cutting was 20 m,the angle was 75°and the blast hole spacing was 1.0 m.The support scheme was the cable reinforcement combined support with bolt,metal mesh,steel belt and

关 键 词：沿空掘巷 近位关键层 切顶卸压 小煤柱 

分 类 号：TD353[矿业工程—矿井建设]