The Numerical Simulation Research Of Cover Caving Sequence With Method Of High Sublevel Bottomless Column Caving Under The Condition Of Thick Overburden Rock

On inspection of Xinjiang Cha gang nuoer Iron mille cover rock is thick, when usingwithout floor pillar caving method abopts caving, caving stope roof of the result is bad,will cause the destruction of roadway deformation and surface subsidence after orcollapsed does not reach the designated position, will lead to geological disasters such aslandslide, landslide. Combining with the field geology investigation and rock mechanicstest in the laboratory，the Finite element analysis ANSYS was applied to establish andsimulate simplified model. The caving sequence of the stope was analyzed by differentexcavation angles through the excavation roadway stress deformation and surfacesubsidence research situation, analysis of displacement, stress and other parameters.Themain conclusions are as follows:(1)In the mining area3185m level detailed engineering geological survey, based onthe distribution of ore to get the fault, the advantages of joint surfaces and density.(2) Cha gang nuoer iron ore rock and tensile specimens, uniaxial compression andshear mechanical test, the measured rock stretching, compression, shear strength andelastic modulus, Poisson’s ratio other mechanical performance parameters. Obtainedusing the strength reduction of rock mechanics parameters.(3)3185m level caving project set up three kinds of working condition of cavingsequence, through the model simulation, comprehensive analysis of three kinds of cavingroadway stability and surface subsidence amplitude under the order, the optimum cavingsequence. Simulation results show that the caving line Angle45°with the strike of theore body of qualifying for the best.