S矿区采动覆岩破坏的实例研究

煤矿地下开采造成水资源的破坏和污染,为了保护S矿区地表水资源和保证安全开采,在分析了该矿区覆岩工程地质特征的基础上,根据该矿区岩层柱状图,建立了煤层覆岩的力学模型,利用FLAC软件计算了煤层开采工作面推进到不同距离时覆岩的应力场,绘出了覆岩塑性区分布图,分析了薄基岩厚松散层下开采煤层时覆岩的应力特征和破坏高度,得出在煤壁和开切眼处覆岩以剪切破坏为主,而采空区上部以拉伸破坏为主;随着工作面的推进,覆岩破坏波及到第四系底部;进一步分析第四系底部粘土层的物理力学性质,得出该粘土层有良好的隔水性,指出工作面可以安全开采,并得到工程验证。

Research on overburden strata failure case after mining operation in S mining area

The coal mining in the underground mine could cause the damage and pollution to the water resources.In order to protect the surface water resources in S mining area and ensure the safety mining operation,base on the analysis of the strata engineering and geological features in the mining area and according to the strata column of the mining area,a mechanics model of the seam and strata was established.With the application of FLAC to calculate the strata stress field when the coal mining face advanced forward in different distances,a distribution figure of the strata plastic area was mapped.The paper analyzed the stress features and failure height of the strata when the coal mining operation in the seam with the thin base rock and thick soft strata.The shearing failure ware mainly occurred at the coal wall and open-off cut and the tensile failure ware mainly occurred at the strata above the goaf.With the coal mining face advanced forward,the strata failure would affect to the floor in the Fourth System.The paper had a detail analysis on the physical mechanics features of the clay layer at the bottom of the Fourth System.The clay layer had a excellent water isolation.Then the paper pointed that the coal mining face could have a safety mining with a engineering certificate.