Surface Subsidence Prediction Model Of Strip Filling Mining In Yushenfu Mining Area

In order to predict the surface subsidence caused by strip filling mining and provide a theoretical basis for the design of surface structures and ecological environmental protection measures,the Yongle Coal Mine is used as the research object,through a combination of theoretical analysis and calculation,numerical simulation experiments and software processing.,Conducted research on the parameters and surface subsidence model of strip filling mining in Yongle Coal Mine,and obtained the following results and conclusions:(1)Strip filling mining in Yongle Coal Mine has a width of 13m and a width of 16m.The solid material quality of cement,fly ash,loess and aeolian sand is 2:2:1:4,solid A paste filling material with a mass concentration of 77%is used as a parameter for strip filling mining in Yongle Coal Mine,Yulin City.(2)In the first stage of strip-packing mining,the maximum load of the strip coal pillars in the coal pillar-packing composite support system is 3.22MPa,and the maximum vertical load of the filling strips is 1.25MPa.The maximum subsidence value of the coal roof is 31.60mm,and the maximum subsidence value of the ground surface is 16mm.In the second stage of strip filling mining,after coal pillar recovery,the stresses on the filling bodies of the first,second,thi rd,and fourth strips are 3.51 MPa,4MPa,4MPa,3.51 MPa,respectively,and 4 strips are filled.The subsidence values of the coal roof are 70mm,80mm,80mm,70mm,respectively.When the 5 remaining coal pillars are mined,the maximum surface subsidence value is 50mm.As the number of mined strips increases,the range of surface subsidence also increases.(3)In the first stage of strip filling mining,based on the thin plate model on the elastic foundation,combined with the probability integration method,the maximum subsurface subsidence value is 14mm.Compared with the calculation result of the numerical simulation test,the relative error of the model is 12.5%.Less than 20%,meeting general engineering applications.The surface subsidence prediction method of strip mining is used to predict the surface subsidence value of the second stage of strip filling mining to a surface subsidence value of 39mm.The surface subsidence caused by strip filling mining can also be regarded as the superposition of the surface subsidence caused by two coal mining methods.The maximum subsidence value caused by strip filling mining is 53mm.Compared with the numerical simulation results,there is an absolute error of 3mm.The relative error of the maximum subsidence value calculated by the model theory is 6%,which meets the general engineering needs.