| After years of mining,it is about to face resource depletion,in order to extend the service life of the mine and improve the safety production guarantee of the mine,so this thesis proposes a steep inclined extra thick coal seam paste filling and mining method.The structural mechanical model of sharply inclined extra thick coal seam beam was constructed,the strength calculation formula of the filling body was derived,and the optimal strength was obtained by combining the mining conditions of the mine.The stability of the filling body as a false top was analyzed.Combined with the equivalent mining height theory,the equivalent mining height of paste filling was obtained according to the sinking amount of roof before filling,the amount of bottom drum before filling,the amount of under-jointing and the compression ratio of the filling body,and the surface subsidence,horizontal deformation,tilt deformation and curvature of the filling mining ground were studied.Through the theoretical calculation and analysis of the strength of the filling body,combined with the specific situation,it is concluded that paste filling mining can better control the surface subsidence deformation.Through the previous observations,the spatial and temporal distribution of rock movement in the filling and mining of sharply inclined extra-thick coal seam paste was studied.The UDEC numerical simulation model of steep-inclined extra-thick coal seam paste filling was established,the effects of different filling rates and filling body strength on surface subsidence during the paste filling and mining process were studied,and the first layer and different elevations were simulated under the condition of selecting the optimal filling rate and filling body strength,and the influence on surface subsidence in the process of paste filling and mining was studied by probability integral MSPS software,which was consistent with the results of numerical simulation research.It is concluded that the use of paste filling mining in Yaojie Three Mines can effectively control the surface subsidence range,so as to achieve the purpose of protecting surface buildings.The research results provide a reference for the engineering practice of sharply inclined extra thick coal seam paste filling and mining in the three mines of Yaojie.The thesis has 65 figures,49 tables,and 86 references. |
