不同加载路径含瓦斯煤岩损伤演化分析  

Damage Evolution Analysis on Gas-Bearing Coal and Rock Under Different Loading Paths

作　　者：辛程鹏 杜锋 赵明洲 刘义磊 李长兴 XIN Chengpeng;DU Feng;ZHAO Mingzhou;LIU Yilei;LI Changring(School of Mining Engineering,Guizhou University of Engineering Science,Bijie,Guizhou 551700,China;School of Emergency Management&Safety Engineering,China University of Mining&.Technology-Beijing,Beijing 100083,China)

机构地区：[1]贵州工程应用技术学院矿业工程学院,贵州毕节市551700 [2]中国矿业大学(北京)应急管理与安全工程学院院,北京100083

出　　处：《矿业研究与开发》2022年第8期153-158,共6页Mining Research and Development

基　　金：国家自然科学基金项目(52004291);贵州省教育厅项目(黔教合KY字[2018]406,[2019]154,[2019]164,[2020]161,[2022]122);毕节市科技计划联合基金项目(毕科联合字G[2019]6号,G[2019]23号,G[2019]24号)。

摘　　要：受载含瓦斯煤岩从屈服变形到失稳破坏后的损伤演化规律与加载应力路径有关,并对煤与瓦斯突出的发生有着一定影响。依据能量守恒理论,分析推导了含瓦斯煤岩从加载到失稳破坏全过程的损伤因子表达式,对常规三轴加载和分段变速加载应力路径下含瓦斯煤岩在全应力应变过程中的损伤因子演化规律进行了计算分析。结果表明:不同加载应力路径下,线弹性阶段受载含瓦斯煤岩的损伤因子等于0,塑性变形阶段损伤因子开始快速增加,应力跌落阶段煤岩损伤因子急剧增长,进入残余强度阶段后,煤岩损伤因子增长率大幅减缓。瓦斯压力增大对煤岩的损伤发育有促进作用,围压增大对煤岩的损伤发育有抑制作用。与常规三轴加载相比,分段变速加载条件下含瓦斯煤岩失稳破坏瞬间的临界损伤因子及进入残余强度时的损伤因子整体上更大。The damage evolution law of loaded gas-bearing coal and rock from yield deformation to instability failure is related to the loading stress path,and has a certain influence on the occurrence of coal and gas outburst.Based on the energy conservation theory,the expression of damage factor in the whole process from loading to instability failure of gas-bearing coal and rock was analyzed and deduced,and the evolution laws of damage factor in the whole stress-strain process of gas-bearing coal and rock under conventional triaxial loading stress path and variable-speed piecewise triaxial loading stress path were calculated and analyzed.The results are concluded under different loading stress paths.The damage factor of loaded gas-bearing coal and rock is equal to 0 in the linear elastic stage,the damage factor begins to increase rapidly in the plastic deformation stage,the damage factor of coal and rock increases sharply in the stress drop stage,and the growth rate of damage factor of coal and rock slows down significantly after entering the residual strength stage.The increase of gas pressure can promote the damage development of coal and rock,and the increase of confining pressure can inhibit the damage development of coal and rock.Compared with conventional triaxial loading,the critical damage factor at the moment of instability failure and the damage factor when entering the residual strength of gas-bearing coal and rock are larger overall under variable-speed piecewise triaxial loading.

关 键 词：含瓦斯煤岩 加载路径 全应力应变 损伤因子 损伤演化 

分 类 号：TD713[矿业工程—矿井通风与安全]