Research on Dynamic Identification Technology of Roof Water Inrush Hazard Sources and Risk Evaluation During Coal Seam Mining

The detection and identification of water inrush hazard sources in the process of coal mining have always been a matter of great concern for coal mine safety production. In the paper, the meaning of the mine water inrush hazard sources is firstly proposed. Then the roof water inrush index evaluation system has been constructed, which is composed of three hazard-causing sources: groundwater sources, water channels and mining influence, and the indicators that are dynamically changing and monitorable with the evolution of mining space are used as the water inrush hazard sources. The hazard sources of water inrush from roof are divided, and the dynamic and static identification methods of various hydrogeological parameters and water inrush hazard sources of mining face are summarized. The dynamic monitoring technology methods such as integration of electric and microseism, optical fiber detection, and borehole television have been developed and applied. The dynamic development process of caving zone and water-conducting fracture zone in 130606 working face of Maiduoshan Coal Mine was monitored in real time by the dynamic monitoring technology of the electric—microseism integration. Through the borehole TV, it is found that the mining-induced overburden fractures are inclined or vertical fractures in Jinjie Coal mine 31114 working face, and the fracture density increases with the increase of hole depth. The whole process of the formation and dynamic evolution of water channel in mining overburden of working face roof was obtained by real-time monitoring methods. Dynamic identification of the measurable hazard factors during the spatial evolution process of overlying strata mining in a typical mine working face was carried out. Combined with the mining situation of the working face in Jinjie Coal Mine, using the spatial multi-criteria decision-making evaluation model, the dynamic evaluation of the water inrush hazard sources and the risk zoning were carried out, and the applicability of the dynamic identification technology and evaluation method in the study area was verified.