巨厚岩层下重复采动采场支承压力分布规律数值分析

以鲍店煤矿10采区为背景,利用UDEC数值软件,研究高位硬厚岩层下近距离煤层开采超前支承压力及硬厚岩层底部应力变化规律。结果表明:上煤层开采时,超前支承压力及影响范围在硬厚岩层破断前达到最大值,硬厚岩层破断后,超前支承压力峰值呈周期性变化,变化范围较小,在硬厚岩层底部离层空间两端出现应力集中现象。下煤层开采时,超前支承压力集中程度高于上煤层工作面,在应力峰值外侧未趋于稳定,出现波浪形变化,硬厚岩层底部未形成显著的应力集中现象。

Numerical Analysis of Stope Abutment Pressure Distribution Laws of Repeated Mining under Large Thick Strata

Taking the 10 thmining area of Baodian coal mine as background and using UDEC to build numerical model,studies the change laws of advance abutment pressure and bottom stress during shortdistance coal seam mining process under high-located hard thick strata.The study results show that:when upper coal seam is mining,advance abutment pressure and its influence scope reach the maximum before the hard thick strata break,after the thick hard strata break,peak value of advance abutment pressure presents periodicity,with small variation,stress concentration phenomenon occurs to both ends of bottom fracture of thick hard strata.When lower coal seam is mining,the abutment stress concentration is obvious than that of upper coal seam,and advance abutment pressure does not tend to stability at peak lateral,present undulation change; bottom stress of thick hard strata would not form remarkable mining stress concentration phenomenon.