Study on Overlying Strata Movement and Surface Subsidence of Coal Workfaces with Karst Aquifer Water

The overlying strata layers of coal workfaces with karst aquifer water normally causes serious safety problems due to the precipitation, drainage and inrush, such as a wide range long term surface subsidence. In this study, by taking 10,301 working faces Daojiao mine in Guizhou Province engineering background, numerical model water-bearing fluid-solid coupling was established using UDEC illustrate laws movement A theory proposed calculate settlement caused based on principle effective stress modified Biot coefficient ?b. results showed that corresponding maximum value (0.72 m) subsidence occurrence were larger than without (e.g., 0.1 m). Moreover, accounted for 17.8% total mining. According field monitoring faces, 0.74 m, which highly consistent simulation theoretical analysis. It verified accuracy reliability study.