下组煤底板断层采动活化流固耦合数值模拟研究

Study on fault mining activation of lower-group coal floor and numerical simulation of fluid-solid coupling

为了探究杨村煤矿十采区10603工作面回采下组煤16上煤层是否对贯穿该工作面的10605F5逆断层产生活化从而导致底板突水,建立了考虑水压力情况下的底板断层活化力学模型及含断层开采的流固耦合数值模型,分析了断层是否会活化及工作面回采过程中顶底板、断层的塑性区变化特征,以及采动应力、承压含水层水压力耦合作用下断层带不同位置的孔隙水压力的变化特征。研究表明,在采动应力及底板含水层水压力耦合作用下,底板承压水会沿着断层带向上导升一定的高度,工作面以下大部分断层仍具有较好阻渗性,底板含水层中的水不会沿着断层导入到工作面,工作面的回采不会导致该断层活化。研究结果可为杨村煤矿下组煤含断层开采底板防治水工作提供较好的指导和借鉴作用。

In order to explore whether mining the No.16up coal seam of lower-group coal in 10603 working face in No.10 mining area of Yangcun Coal Mine makes the activation of the 10605F5 reverse fault and causes gushing water from the floor,a mechanical model of floor fault activation considering water pressure and a numerical model of fluid-solid coupling including fault mining were established.The paper analyzes whether the fault will be activated,the variation characteristics of plastic zone of roof and floor and fault during the mining process,and the pore water pressure variation characteristics at different positions of the fault zone under the coupling effect of mining stress and confined aquifer water pressure.The research shows that under the coupling action of the mining stress and the water pressure of the floor aquifer,the confined water of the floor will guide up a certain height along the fault zone,and most of fault area below the working face still have good impermeability.Therefore,the water of the floor aquifer will not inflow to the working face along the fault,and mining in the working face will not lead to fault activation.This study results can provide good guidance and reference for the water control of lower-group coal of fault mining floor in Yangcun Coal Mine.