Mine water inrush accompanied by strong mine pressure and sediment crushing frequently occurs in northwest China. As the direct hydraulic resource and pathway of this water inrush, which are induced by mining activity, cannot be explored directly using borehole and geophysical prospecting prior to mining, it is extremely difficult to assess and predict the complex water hazard effectively. Recently, it has caused serious casualties and property damage. In this study, in-situ monitoring tests, simulations and theoretical analysis were performed to explore the evolution mechanism and prediction method of the destructive mine water hazard. First, water leakage, borehole video capture, water level of Cretaceous aquifer, mine pressure, micro-seismic monitoring were performed to study the strata structure evolution, fracture characteristics, and ground water seepage of overburden under longwall mining. Based on the overburden conditions, physical and numerical simulation are conducted to explore the evolution mechanism of water inrush accompanied by strong mine pressure and sediment crushing. Further, mechanical and statistic analysis was adopted for the effective prediction method and controlling technology. Results show that the direct water resource is from the mining-induced closed separation layers near confined aquifer. The evolution process of severe water inrush from separation layers involves the formation of closed separation layers, collection of water from confined aquifer, fracture of water-resisting layer. The buckling failure of high-level strata causes the strong mine pressure, and the weak cemented Jurassic strata leads to the sand crashing. On the basis of the formation conditions of water inrush accompanied by strong mine pressure and sediment crushing, some prevention methods, including risk zoning of mine areas, strata prediction indicators, indexes warning system, and drainage borehole from separation layers, are proposed to systematically predict and control the destructive mining-induced water hazard.
 

mine water inrush; separation layers; overburden behavior; evolution mechanism; prevention methods