近距离煤层上行开采围岩应力演化特征分析

基于潘一东煤矿地质概况及原始地应力测试数据，采用相似模拟与数值模拟相结合的方法，分析了近距离煤层上行开采过程中两煤层采场超前支承压力变化规律和覆岩裂隙发育特征。结果表明:下保护层开采弱化了覆岩关键层的承载能力，采空区后方形成的覆岩断裂线对上覆被保护层基本顶初次垮落步距具有一定影响；下保护层采场超前支承压力峰值呈线性增长趋势，而被保护层采场超前支承压力峰值受保护层采动影响呈增大—稳定—减小的趋势，工作面推进距离达到1/2“见方”及“见方”时，悬顶岩梁会发生大面积垮落失稳，应注重采场动力灾害防治工作。

Stress distribution of surrounding rock in closer coal seam during the ascending mining

Based on Panyidong Coal Mine geology and original stress test data，stress evolution law of surrounding rock and the overlying rock fissure developmental features of two coal seam mining field have been analyzed by similar simulation test and numerical simulation.The results showed that the overlying rock fracture line formed in the lower coal seam mining has a certain influence on the first caving roof of the upper coal seam；under the protective layer，the peak pressure of advance support pressure increases linearly，and the peak pressure of the advanced support pressure of the stope is increased，stabilized and decreased by the mining of the protective layer，when the stope advancing distance to "square" and "square" multiples of half，the roof rock beam will collapse in large area and instability，should pay attention to the prevention and control of mining power disaster.