【摘要】 以某矿6302工作面为背景,采用理论分析、数值模拟和现场实测等方法研究了对硬厚岩层下煤层重复采动的应力演化规律。研究结果表明:在多煤层重复采动过程中,下层煤的卸压边界角随着推进步距的增大,先增大后趋于稳定,2层煤之间岩层间隔起到了隔板的作用,下层煤上方的集中应力由于层间岩层的影响发生衰减。这一趋势随层间岩层厚度增加,衰减系数减小,相同岩层厚度情况下,岩层硬度增加,衰减系数越小。更多还原

【Abstract】 Based on the engineering background of 6302 working face of a coal mine,stress evolution rules by methods of theoretical analysis,numerical simulation and field measurement under hard thick strata are studied. The results showed that in multiple coal seams repeated mining process,the lower coal unloading boundary angle interval after the first increases stability with the increase of advance,the effect of interval of between two layers of coal strata,the lower stress concentration occurrence attenuation due to the influence of this layer above the coal. This trend with the increase of thickness of interval layers,the attenuation coefficient become smaller. The same strata thickness,rock hardness increases,the attenuation coefficientbecome smaller.更多还原