巨厚坚硬顶板工作面的底板破坏规律

Analysis of failure law of the working face floor under thick- hard roof

针对郭庄矿开采9＾＃煤时受巨厚坚硬顶板和底板奥灰水双重威胁的情况，利用现场钻孔注水试验手段与数值模拟的方法对9＾＃煤底板进行破坏深度探测及破坏规律的研究．现场钻孔注水试验结果表明，工作面煤层底板监测钻孔控制深度内的底板岩层均发生了不同程度的破坏，最大破坏深度介于18．80～21．00m，9＾＃煤与下伏奥灰层间距不足20m；数值模拟结果表明，坚硬顶板条件下，强制放顶比充填开采对煤层底板产生的破坏程度大．

Based on special case that the 9^# coal mining is under double threat of the thick - hard roof and Ordovician limestone water inrush from floor, a survey and research on the 9^# coal floor failure law is conducted with on -site water injection test and numerical simulation. On -site water injection test indicates that different degrees of damage occurred within the scope of monitoring of working depth is up to 18.80 -21.00 m; and the distance between 9^# coal and face coal seam floor and the max failure Ordovician limestone aauifer is less than20 m; Simulation results show that, as for the degree of damage of coal seam floor under thick - hard roof, forced carving is more destructive than filling mining.