Simulation analysis of water resource damage feature and development degree of mining-induced fracture at ecologically fragile mining area

Mining-induced water damage has become one of wide concerned issues in contemporary society. Knowing the main causes to water resource damage (especially the superficial aquifer damage) as well as the damage mode is the basis for realizing water conservation. In this paper, the mining height and position of aquifuge are regarded as the main influencing factors in analyzing the change of aquifer. Taking the geological conditions of Yili No. 4 coal mine as an example, a total of 18 numerical analysis models with different mining heights (3, 5, 8, 10, 15, 20m) and different positions of aquifuge (upper, middle and bottom) as changing conditions were established using universal distinct element code discrete element simulation software. The variation characteristics of water resources in aquifers after disturbance were studied. The variation of water pressure with mining height and position of aquifuge was analyzed. The variation of water pressure in aquifer was proposed as a novel criterion for distinguishing the development degree of mining-induced fracture. The criterion for determining the failure of aquifer was established based on the ratio of water pressure change and mining height (P/H), which is a pioneering research on the relationship between mining-induced fracture and aquifer failure. This study provides a reference for evaluating the development degree of mining-induced fracture and provides theoretical basis for analyzing the coupling relationship between mining and water resource change in aquifer and for water conservation at ecologically fragile mining area.