采空区上覆岩层应力恢复规律的模拟分析  

Numerical Simulation Analysis on Stress Re-establishment Law of Overburden Strata over Goaf

作　　者：许国胜 许胜军[2] 李德海[2] 李回贵[1] XU Guo-sheng;XU Sheng-jun;LI De-hai;LI Hui-gui(School of Mining Engineering,Guizhou University of Engineering Science,Bijie 551700,China;Mining Research Institute,Henan Polytechnic University,Jiaozuo 454000,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551700 [2]河南理工大学矿业研究院,河南焦作454000

出　　处：《煤炭技术》2021年第8期8-11,共4页Coal Technology

基　　金：贵州省教育厅项目(黔科合KY字[2018]388);毕节市科技局科技联合基金(毕科联合字G[2019]1号);贵州工程应用技术学院科学研究基金(院科合字G2018012号)。

摘　　要：通过数值模拟方法对工作面支承压力及采空区应力的分布规律进行分析,得到工作面及岩层采空区应力恢复距离在覆岩内部的变化规律。依据煤层极限平衡区和弹性区的支承压力分布函数的表达式,通过载荷守恒原理对采空区应力恢复函数进行分析,得到了采动岩层采空区应力恢复函数中增长系数的变化规律。结果表明:工作面支承压力峰值位于煤壁前15 m附近,其峰值为18.5 MPa,应力集中系数为2.52,上述参数与理论计算结果误差较小,证明了数值模型计算的准确性;当岩层与煤层的垂距越大时,采空区应力恢复距离越大,且岩层采空区应力恢复距离与其和煤层的距离呈现线性增加的关系。根据采动岩层空间载荷守恒原则,采动岩层采空区应力恢复函数的形态呈现出“上凸”的形态,并且岩层与煤层垂距越大,其“上凸”的形态越明显,采空区应力恢复的过程越快。Through the numerical simulation method, the distribution law of working face abutment pressure and goaf stress is analyzed, and the stress re-establishment distance variation of working face and overburden strata is obtained. According to the abutment pressure distribution function in limit equilibrium zone and elastic zone of coal seam, stress re-establishment function of goaf is analyzed by the principle of loading conservation, and the variation of function growth coefficient of goaf in mining strata is obtained. The results show that the peak value of abutment pressure is 18.5 MPa and the stress concentration factor is 2.52, which is located about 15 m in front of the coal wall. The error between the above parameters and the theoretical results is small, which proves the accuracy of the numerical model. When the vertical distance between the strata and the coal seam is larger, the recovery distance in goaf is larger, and the relationship between the recovery distance and its distance from the coal seam increases linearly. According to the principle of loading conservation of mining-induced strata, the shape of stress re-establishment function of mining-induced strata presents "upward convex" shape,and the larger the vertical distance between the strata and the coal seam is, the more obvious the "upward convex" shape is, and the faster the process of stress recovery in goaf is.

关 键 词：长壁工作面 支承压力 采空区应力恢复 载荷守恒 

分 类 号：TD322[矿业工程—矿井建设]