The mining stress will be abnormally concentrated under the hard and thick overburden. The numerical simu-lation method was used to study the evolution law of mining stress under overlying hard thick key layer and the influence of mining environment on mining stress. The study showed that with the increasing distance of work face,the supporting pressure in front of the working face is growing, but the growth rate slowed down gradually, decreased rapidly breaking the abutment pressure. Influence of the working surface boundary conditions and the hard thick key layer thickness on the stress of mining effect was obvious,showing that with the number of adjacent mining goaf increasing,the peak stress increases before breaking, and gradually decreases after breaking. With the hard thick key layer thickness increasing,the abutment pressure peak at the front decreased gradually,and sharpened after breaking. The research results can provide a theoretical basis for the prediction and prevention of rockburst in the mining of high hard and thick strata,and it has a certain guiding significance for the safe production of the working face.%上覆高位硬厚关键层下开采,采动应力会异常集中.采用数值模拟的方法,研究了上覆硬厚关键层条件下采动应力演化规律,并分析了开采环境对采动应力的影响.研究表明:随工作面回采距离不断增加,工作面前方支承压力不断增长,但增速逐渐放缓,破断后工作面支承压力迅速降低.工作面边界条件和硬厚关键层厚度对采动应力的影响作用较为明显,表现为随相邻采空区数目的增加,破断前应力峰值逐渐增加,破断后应力逐渐降低;随硬厚关键层厚度的增加,工作面前方支承压力峰值逐渐减小,破断后支承压力峰值降低幅度逐渐增加.研究结果可为高位硬厚岩层下开采时冲击地压的预测与防治工作提供一定的理论基础,对于保证工作面的安全生产具有一定的指导意义.
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