Safety Impact Assessment Of Coal Mining Under Daping Mine Reservor

China is a large country of population, and the rapid development of the national economy since the reform and opening, the coal resources must be increased year by year, resulting in less coal resources. If the dam and the safety of the mine is ensured, the coal resources with large reserves and the difficulty of exploiting the coal resources can improve the economic benefit and ease the tension of energy.The research of the surface movement failure law and the overlying rock damage lead to the height of the crack zone is the important basis for the safe mining of the water body.. In this paper, in summing up the basis of Daping Mine of natural geography and geology, the range of surface movement and characteristics and surface water leakage risk etc. were detailed analysis, and the following conclusions are obtained:1. Using the probability integral method, after the seven steps are collected, the maximum surface subsidence is 10.56 m, the average influence radius is 531.2m.2. Using FLAC3 D numerical simulation method, after the seven steps, the maximum surface subsidence is 14.51 m, the average influence radius is 516.2m.3, the distance of S2S2 working face distance from dam is about 900 m, and the surface movement caused by large- level mine reservoir is less than dam body.4, According to the "three rules" empirical formula calculation, the "two belts" development height(77.82m) plus protection layer thickness for 123.82 m.5, Calculated using numerical simulation method, the seven step after mining, "two belts" development highly(94.5m) plus left height of waterproof coal column for 140.5m.6, mining "two belts" of 1, 2# coal seam caused by development of the top, located in the Cretaceous of relative water resisting layer, overlying and quaternary aquifuge, so it will not cause surface water leakage into the mine.