The Law Of Surface Subsidence Of He Gang Jiao Tong Coal Mine And The Application In Ecological Restoration

With the exploitation of coal mines,the ecological problems become more and more obvious.Accurate prediction of surface subsidence is a necessary guarantee for targeted ecological restoration measures.Taking Hegang Jiaotong coal mine as an example,the law of surface movement and deformation in coal mining is studied and the corresponding ecological restoration measures are put forward in this paper.The main results of the paper are as follows.The final measured sinking value and the trend of horizontal movement of Hegang Jiaotong coal mine is 1172 mm and 324 mm,the maximum tilt is 56.3 mm/m,the maximum deformation is 21 mm/m,the comprehensive boundary angle is 63.6°and the full mining angle is 65.2°and the comprehensive moving angle is 52.8°.The probability integral method is used to fit the measured curves,and the expected integral parameter is obtained.The subsidence coefficient is 0.59,the tangent is 2.21,the mining influence propagation angle is 87.5°,the horizontal coefficient is 0.27 and the inflection point offset is 38m.The model of coal seam and overlying strata of Hegang Jiaotong coal mine is established with the FLAC3D numerical simulation,and the maximum subsidence value and the maximum horizontal displacement value are got which are1053 mm and292 mm.According to the full extraction conditions of measurement,simulation and probability integral method of surface movement and deformation curves,the probability integral method and FLAC3D numerical simulation are basically applicable to the prediction of the surface movement and deformation of Hegang Jiaotong coal mine.But the effect of FLAC3D numerical simulation is not as good as probability integral method,and the accuracy of prediction of probability integral method also needs to be improved.In this paper,the probability integral method is modified.The corrected sinking range is 0.0068W₀⁰.09W₀?W₀ is the maximum subsidence value of probability integral method?.The corrected value is 0.05W₀ and the corrected error value is 6.50%.The corrected range of horizontal movement is0.009U₀⁰.07U₀?U₀ is the maximum horizontal moving value of probability integral method?,the corrected value is0.074U₀,and the corrected error value is 6.68%.The surface subsidence and horizontal movement values modified are similar to the measured values when the corrected errors are between 6.50%and 6.68%.The corrected range and corrected value is verified by the tendency measured value and the probability integral method.The corrected error value of the tendency surface subsidence is 4.54%,and the corrected error value of the horizontal movement is 6.32%,which indicates that the correction formula of the surface subsidence and horizontal movement is reasonable.This paper get the Hegang Jiaotong coal mine working face's mining surface movement deformation law.With the mining working face advancing,range and maximum surface subsidence values are the central position above goaf,and the surface subsidence value about the gob of maximum subsidence value is symmetrical.In order to reduce the impact on the ecological environment,ecological restoration measures are put forward for the surface movement and deformation of the Hegamg Jiaotong coal mine.