Comprehensive safety factor of roof in goaf underdeep high stress  

深部高应力下采空区顶板综合安全系数

作　　者：JIANG Li-chun JIAO Hua-zhe WANG Yu-dan WANG Ge-ge 姜立春;焦华喆;王玉丹;王格格(School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,China;Institute of Safety Science and Engineering,South China University of Technology,Guangzhou 510640,China;School of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,China)

机构地区：[1]School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510640,China [2]Institute of Safety Science and Engineering,South China University of Technology,Guangzhou 510640,China [3]School of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,China

出　　处：《Journal of Central South University》2021年第2期595-603,共9页中南大学学报（英文版）

基　　金：Projects(51974135,51704094)supported by the National Natural Science Foundation of China;Project(2016YFC0600802)supported by the National Key Research and Development Program of China;Project(2020M672226)supported by the China Postdoctoral Science Foundation。

摘　　要：The safety factor of roof under deep high stress is a quantitative index for evaluating roof stability.Based on the failure mode of surrounding rock of stope roof,the mechanics model of goaf roof is constructed,and the internal force of roof is deduced by the theory of hingeless arch.The calculation method of roof safety factor(K)under the environment of deep mining is proposed in view of compression failure and shear failure of roof.The calculation formulas of shear safety factor(K1),compression safety factor(K2)and comprehensive safety factor(K)of roof are given.The influence of stope span and roof thickness on roof stability is considered in this paper.The results show that when the roof thickness remains constant,the roof safety factor decreases with the increasing of the stope span;when the stope span remains constant,the roof safety factor increases with the increasing of the roof thickness.The deep mining example shows that when the stope span is 30 m and the roof thickness is 10 m,the roof comprehensive safety factor is 1.12,which indicates the roof is in a stable state.深部高应力下顶板安全系数是评价顶板稳定性的定量评价指标。基于采场顶板围岩破坏形式,构建了空区顶板力学模型,利用无铰拱理论推导顶板内力大小。针对顶板压缩、剪切破坏形式,提出了深部开采环境下顶板安全系数(K)的计算方法,给出矿柱剪切安全系数(K1)、压缩安全系数(K2)和综合安全系数(K)的计算式,研究采场跨度、顶板厚度对顶板稳定性的影响。结果表明,当顶板厚度一定时,顶板安全系数随着采场跨度的增加而递减;当采场跨度一定时,顶板安全系数随着顶板厚度的增加而递增。该矿深部开采实例表明,在采场跨度为30 m,顶板厚度为10 m的条件下,顶板综合安全系数为1.12时,顶板处于稳定状态。

关 键 词：deep mining high stress hingeless arch comprehensive safety factor stope span 

分 类 号：TD327.2[矿业工程—矿井建设]