针对祁东煤矿多起采煤工作面突水灾害问题,采用现场测试和模拟实验方法,对松散承压含水层下采煤顶板导水裂隙发育特征与突水机理、突水危险区域预测与突水灾害防治对策等进行了深入研究.结果表明:祁东煤矿采煤工作面每次突水前都伴随有压架现象,说明工作面突水灾害的发生与覆岩破断运动紧密相关.由于松散承压含水层的载荷传递作用,易导致覆岩关键层产生复合破断,引起松散承压含水层下部较大范围岩层的整体破断,使得顶板导水裂隙发育高度异常增大而沟通含水层,这是引发松散承压含水层下采煤发生异常突水灾害的根本原因.提出了松散承压含水层下采煤突水危险区域的预测方法和突水灾害防治对策,指导了祁东煤矿松散承压含水层下采煤突水灾害的防治实践.
According to the several water inrush disasters in Qidong coal mine,we adopt field measurements and simulation experiments in this paper,to study the development characteristics of water flowing fracture,water inrush mechanism,prediction of water inrush zone,and prevention strategy,et al,while mining under the unconsolidated confined aquifer.The results show that the support crushing accident appeared before each water inrush in Qidong coal mine,which proves that it exist close relationship between water inrush accident and overburden moment.Due to the effect of load transfer of the unconsolidated confined aquifer,the adjacent key strata are prone to compound breakage,which can cause the bedrock broken as a whole in a wide range below the unconsolidated confined aquifer.Therefore,the height of water flowing fractured zone becomes obviously larger and then communicates the unconsolidated confined aquifer.This is the fundamental reason for the abnormal water inrush disaster when mining under the unconsolidated confined aquifer.Finally,prediction method to determine water inrush zone and the prevention strategy were put forward here,which guided the water inrush prevention effectively when mining under the unconsolidated confined aquifer in Qidong coal mine.