特厚煤层采动覆岩裂隙演化规律物理及数值模拟研究  

Physical and Eumerical Simulation Study on the Evolution Law of Overlying Rock Fractures Caused by Mining in Extra-thick Coal Seams

作　　者：陈德山 杨婉欣 张建江 焦健 周继国 CHEN Deshan;YANG Wanxin;ZHANG Jianjiang;JIAO Jian;ZHOU Jiguo

机构地区：[1]兰州石化职业技术大学资源环境工程学院,甘肃兰州730207 [2]甘肃靖远煤电股份有限公司魏家地煤矿,甘肃白银730913

出　　处：《中国矿山工程》2023年第4期55-61,共7页China Mine Engineering

基　　金：甘肃省教育厅创新基金项目(2022 A-220);兰州石化职业技术大学教科研项目(KJ2021-10)。

摘　　要：为准确掌握靖远矿区特厚煤层采动覆岩裂隙演化分布规律,为回采过程中瓦斯抽采系统的布置提供依据,以魏家地矿北1103工作面为试验原型,采用物理相似模拟和UDEC数值模拟相结合的方式开展工作面回采试验,统计特厚煤层采动覆岩周期来压规律,分析回采过程中围岩应力的变化规律,研究特厚煤层采动裂隙的演化分布规律。结果表明:最后一次周期来压时,裂隙带和垮落带停止向上发育,高度分别为39.1 m和127.9 m;围岩应力集中区应力呈轴对称分布,大小为8.94~19.8 MPa,卸压区的应力呈抛物线分布,分大小为0.22~1.46 MPa。卸压区的高度及位移最大区高度随煤层采高的增大逐渐增大,其中卸压区高度的增高趋势趋缓,变化范围为70.4~81.2 m;位移最大区的高度变化范围为52.4~74.8 m,其宽度随采高的增大而减小,变化范围为102.3~71.6 m;采高从6 m增加到12 m时,主关键层出现显著的下沉变形,上方无明显裂隙,下方裂隙激增,采空区压实区宽度减小、高度增加。In order to accurately grasp the evolution and distribution law of overlying strata fissures in extra-thick coal seam mining in Jingyuan mining area,and provide a basis for the layout of gas extraction system in the course of mining,the north 1103 working face of Weijiadi mine was taken as an experimental prototype,by means of combining physical similarity simulation with UDEC numerical simulation,the mining test of working face is carried out,and the law of cyclic weighting of overlying strata in extra-thick coal seam is calculated,and the variation law of surrounding rock stress during mining is analyzed,the evolution and distribution law of mining fracture in extra-thick coal seam is studied.The results show that the fracture zone and the collapse zone stop developing upward at the last periodic weighting,the heights are 39.1 m and 127.9 m respectively,and the stress distribution in the stress concentration zone of the surrounding rock is axisymmetric,the distribution range is 8.94 MPa something 19.8 MPa,the stress distribution in the pressure relief area is parabola,and the distribution range is 0.22 MPa something 1.46 MPa.The height of the pressure relief area and the height of the maximum displacement area gradually increase with the increase of coal seam mining height,and the increase trend of the height of the pressure relief area tends to be slow,the variation range is 70.4 m something 81.2 m,the height of maximum displacement area is 52.4 m something 74.8 m,its width decreases with the increase of mining height,and the variation range is 102.3 m something 71.6 m,the main key stratum has obvious subsidence deformation,no obvious fissure above,fissure surge below,the width of compacted area in goaf decreases and the height increases.

关 键 词：特厚煤层 物理模拟试验 数值模拟试验 采动裂隙 

分 类 号：TD352[矿业工程—矿井建设]