晋城矿区下保护层开采覆岩运移及裂隙演化规律研究

发布时间：2019-06-05 18:21

【摘要】：针对晋城矿区开展下保护层开采试验,采用模拟试验,现场实测等手段研究下保护层开采覆岩运移、裂隙动态演化特征及被保护层变形规律。模拟结果表明:伴随基本顶的周期破断,采动裂隙呈梯形演化,贯通的竖向裂隙没有连通至上被保护层。保护层开采后,被保护层下沉平缓连续,膨胀变形率保持在0.5%左右。深基点位移计动态监测下保护层94302工作面开采覆岩运动全过程,得到了监测岩层的移动曲线,掌握了上覆岩层横向三区、纵向三带离层裂隙时空演化规律。通过钻孔电视观测覆岩裂隙分布特征及被保护层煤体结构变化,得到冒落带高度2.2~4.5 m,裂隙带高度20.0~25.7 m,发现被保护层煤体受采动影响产生水平方向为主的小角度次生裂隙。
[Abstract]:In view of the mining test of the lower protective layer in Jincheng mining area, the migration of overlying rock, the dynamic evolution characteristics of fissures and the deformation law of the protected layer in the mining area of Jincheng mining area are studied by means of simulation test and field measurement. The simulation results show that with the periodic fracture of the basic top, the mining fracture evolves ladder, and the vertical fracture through is not connected to the protected layer. After the mining of the protective layer, the subsidence of the protected layer is gentle and continuous, and the expansion deformation rate is kept at about 0.5%. Under the dynamic monitoring of deep base point displacement meter, the whole process of overlying rock movement in protective layer 94302 working face is obtained, and the movement curve of monitoring strata is obtained, and the temporal and spatial evolution law of cracks in transverse three zones and longitudinal three zones of overlying strata is mastered. The distribution characteristics of cracks in overlying rocks and the structural changes of coal bodies in protected strata are observed by drilling TV. The height of caving zone is 2.2 鈮，

本文编号：2493734