Mine Surface Mining Destruction And Underground Water Inflow Forecasting

Nowadays, energy is an important factor restricting China’s economic development,and coal is the main energy reliability of China’s energy structure.In the recentyears,with the increase in the number of mines and the mining depth,the impact ofmining disasters is increasing.Surface deformation and the mine flood are commonproblem in mining, which are the focus of our current research work.This paper mainly used numerical simulation method to study. Firstly, based on theUDEC software, surface deformation and rock movement of different mining section inQianyang coal mine are simulated.The laws of the horizontal and vertical movementand strata movement of ground monitoring points of mine one, two sections of differentface after mining are summarized.And the possible geological disasters caused bymining in each section and prevention measures are discussed.Secondly,using BP neuralnetwork MATLAB, underground water inflow forecasting model in different periods ofmining in Qianyang coal (mining states and stop mining state) is built.The predictionresults are evaluated respectively.Main conclusions are as follows:(1) The horizontal direction movement law: the impact of each seam mining in firstsection on horizontal movement of the surface has little difference; the shape of surfacemining horizontal movement curve after mining in second section are basically samebut has a difference between the displacement. And the number, width, length and depthof cracks caused by mining in the slope near the shoulder in second section of eachseam mining face are significantly increased.(2) The vertical direction movement law: the impact of each seam mining in firstsection on surface subsidence has little difference; the morphological changes of thesinking curve of the second section are consistent with the first section. The subsidenceof the second section is significantly larger than the first section.(3) The first coal face of the first layer of coal in the each section has the greatestimpact on the deformation and failure of the surface and the overlying rock, far greaterthan the lower seams within the same section of the mining face.Caving and fracturezones caused by the mining never develop to the surface in the first section.After thesecond section mining working face mining, fractures of goaf through to the position,where slope shoulder of the first level of slope platform is, while other surface cracks of first slope platform further down the development.(4) At mining state, the test results of water inflow forecasting network model ofChung Qianyang coal mine are good, and its reliability is87.5%, with high predictingability;(5) At stopping mining state, network test approximation effect is relatively poor,and the credibility is only75%, the main performances is that the inflow of networkoutput in August, September, October of2013was larger than the actual water inflow,and the main reason may be the cracks formed at mining stage slowly closed with timeafter stop mining, resulting in the output value of water inflow of network significantlygreater than the actual water inflow water inflow.