近距离煤层下行跨煤柱开采巷道的合理布局

为了探究遗留区段煤柱对下伏回采巷道布局的影响,以煤峪口矿为工程背景,通过最大主应力集中系数判别底板应力增高区,采用理论解析、编程计算、数值模拟的方法,研究了不同开采阶段底板应力增高区的演化特征.结果表明：区段煤柱宽度、埋深、煤柱边缘至峰值区的距离及其垂直应力峰值控制着应力增高区的发育,采空区应力恢复特征对应力增高区的影响可以忽略;对比各模拟方案中煤柱-巷道错距与应力增高区对下煤层的影响范围峰值,并结合采空区应力逐渐恢复及工作面矿压显现的区域化特征,认为煤柱-巷道错距10～15 m为优选区间.选择12 m错距进行工业试验,取得了良好效果.

Rational Layout of Roadway for Downward Cross-Pillar Mining in Close Distance Coal Seams

Meiyukou coal mine was taken as engineering case to explore the influence of remnant coal pillar on the layout of underlying roadway. The maximum principal stress concentration coefficient was used to identify the concentrated stress zone in the floor. The evolution characteristics of concentrated stress zone in the floor at different mining stages were studied by means of theoretical analysis, programming calculation and numerical simulation. The results show that the width and the buried depth of pillar, the distance from edge of pillar to peak zone and the peak value of vertical stress control the development of concentrated stress zone in the floor. The influence of stress recovery characteristics of goaf on the concentrated stress zone can be ignored. Comparing the peak value of the influence range of concentrated stress zone on the lower coal seam and the staggered distance between coal pillar and roadway in each simulation scheme, and combining with the gradual recovery of stress in the goaf and the regionalization characteristics of ground pressure in longwall face, it is considered that the reasonable staggered distance range is 10~15m. Choosing staggered distance of 12m for industrial test has achieved good application effect.