覆岩含水层采动破坏机理流固耦合分析及保护措施研究

为了研究煤层开采对覆岩含水层的破坏机理,采用岩石破裂过程流固耦合分析系统UDECFlow,根据老三沟井田6煤工作面地质条件,对覆岩含水层(砂砾岩、细砾岩和粗砂岩含水层)的破坏过程进行数值模拟。模拟结果显示,随着工作面的推进,裂隙不断向上发育,直接顶、基本顶的相继破断和垮落导致了导水裂隙的形成;同时随着工作面的推进,先前生成的一些裂隙出现了闭合,而工作面附近又产生新的裂隙。以6煤为例,对上覆含水层的保水开采难度进行分级,并提出了相应的保水开采技术,如加快工作面推进速度、注浆加固、降低采高、充填开采及部分开采等,将指导6煤开采时覆岩含水层保护,对同类开采地质条件下的矿井有较好的指导借鉴意义。

Fluid-solid Coupling Analysis of the Damage Mechanisms of Overburden Aquifer and the Research of Protection Measures

In order to study the damage mechanism of overburden rock aquifer after coal mining, utilized the fluid-solid coupling analysis system UDEC-Flow of the damage process with rock, according to the geological conditions of working face of the No.6 coal seam in LaoSan-gou coalmine, the damage process of the overburden rock aquifer (the aquifer of glutenite, fine conglomerate and coarse sandstone) was analyzed by numerical simulation method .The simulation results show that the crack keep continuously up growth with the working face advancing, the successively breaking and caving of the immediate roof and basic roof led to the formation of water flowing fracture; simultaneously with the face advancing, the previously generated cracks appeared closed, and near the working face generated new cracks again. Taking the No.6 coal seam for instance, the difficulty of protecting aquifer was graded, and proposed the protection technology of overburden rock aquifer, Such as speed up the working face advancing, grouting reinforcement, reducing the mining height, Filling mining and technical of partial mining and so on. Research resluts could provide references for the No.6 coal seam and coalmining with the same geological conditions.