Study On Surface Deformation Rule Of Deep Backfilling Mining In Tangkou Coal Mine

With the continuous increase of coal pressure in the“three downs”and the coal seam mining depth exploitation to deep,in order to maximize the liberation of“three downs”coal compaction and solve the surface subsidence problem faced by deep mining,and extend the service life of mine exploitation,this paper taking Tangkou Coal Mine as an example,the numerical simulation method is used to study the surface deformation law of backfilling mining,and the differences between the surface deformation laws of deep and shallow backfilling mining are analyzed and summarized.The mathematical calculation method is used to estimate the surface subsidence of Tangkou Coal Mine.The accuracy of the numerical simulation was further verified,and the conclusions consistent with the numerical simulation were obtained.The main work and results are as follows:?1?Combined with the actual situation of tangkou coal mine,the anti-deformation capability of ground structure is analyzed.By analyzing the influence of various factors on the surface deformation of solid backfilling mining,the controllable influencing factors of surface deformation in backfilling mining,namely mining width,propulsion distance and enrichment rate,are summarized,which provides a theoretical basis for the design of numerical simulation excavation scheme.?2?FLAC^3D simulation software was used to establish a numerical simulation model of backfilling mining to simulate the influence of the mining width,advance distance and backfilled ratio of backfilling mining on the surface movement law under different mining depths.Numerical simulation results show that the surface deformation value,increases with the increase of mining width or advance distance,and increase the speed of the first increases then decreases,until achieve full mining,the surface deformation value increases with the mining width and advance distance reach a logarithmic relation increases,the surface deformation value relations with almost linearly with the increase of backfilled ratio,and has nothing to do with the size of the backfilled ratio 0069nfluence scope.?3?The contrast of deep mining and shallow backfilling mining surface deformation law is different,it is concluded that the deep backfilling mining all the indexes?except surface deformation area?are less than shallow backfilling mining,and deep backfilling mingning of surface subsidence,horizontal movement,horizontal displacement,inclination deformation and horizontal deformation has a linear relationship between reduced along with the increase of mining depth,the surface deformation range with the increase of mining depth increase a logarithmic relationship.?4?Through the analysis of the measured data of surface subsidence caused by the slumping method,the expected parameters of the surface subsidence of the backfilling mining were obtained.The reference range is selected,and the parameters of surface subsidence prediction are selected.The parameters are substituted into the surface subsidence prediction model based on the equivalence mining method.The deformation of the ground surface is calculated in the first stage.Within the scope,the conclusion of the fortification standard is not exceeded.The predicted results of surface subsidence show the same rules as the numerical simulation results,further verifying the reliability of the numerical simulation results.