Mathematical Model Of Caving Body And Computer Simulation

The non-pillar sublevel caving method has many virtues,such as high strength of mining,production safety,ect.So it's widely used in metal iron ore mine at home and abroad currently.However,the ores fall and are released under a loose cover-layer-rock in the non-pillar sublevel caving method,and it's easily to cause the ore loss and dilution,and this problem has not been very good soluted.Caving body is the ore heap which is formed from the loose cover-layer-rock by the blasting ore body,it's the object of released ore.Its form has a great influence on the ore loss and dilution.But the shape of caving body in the cover-layer-rock is difficult to observe,and there is no good way to confirm it.So confirming caving body's shape has important theoretical significance and practical value for optimizing the stope structural parameter,reducing the ore loss and dilution and improving the mine economic benefits.Based on the laws of ore movement,loose media theory,minimum energy dissipation and dissipative structure theory,the formation mechanism of caving body is analyzed,and the mathematical model of caving body shape is established and solved.The shape of caving body is calculated by MATLAB software.The PFC2 D software is used to simulate the shape of caving body under different stope structure parameters.The effects of caving body shape on the loss of ore is experimented in the liboratory.the results are as follows:1.To the ore drawing theory,loose media theory,minimum energy dissipation theory and dissipative structure theory,it is deduced that caving body and loosing body are similar ellipsoid.2.The mathematic model of caving body is established,the method and steps of establishing the caving body model are determined.On this basis,the MATLAB program is compiled to calculate caving body shape under different stope structure parameters,and the results are in line with mine practice.3.The PFC2 D software is used to simulate the shape of caving body.Compareing with the result,the feasibility of the model is verified.4.With the the automated single ore dressing system,the release ore experiments is calculated.The result shows that:When the section height is 18 m,the road width is20 m and collapse width is 3m,the mineral loss is the lowest and the caving body has the best shape.The study has guiding significance for the optimization of structural parameters of mine with the non-pillar sublevel caving method and the reduction of ore loss.