Numerical Simulation Research Of Presplit Blasting Of Axial Decoupling With Air-deck Charge

The application of presplit-blasting is extremely wide.As for the heavy broken orebodies in the deep, Influenced by mining the orebodies, the ore-rock is disturbed, forming fractured zones, which causes complexion and difficulties in selecting the mining techniques. Based on the research project in Xincheng Gold mine, the key technologies used in strengthen mining in section pre-splitting extrusion blasting in the deep-hole mining process in heavy cracked mine were studied. By means of numerical simulation, the software ANS YS/LS-DYNA3D was used for dynamic analysis. The main contents and results were as follows:(1) The best location of air layer was examined. Simulation the pre-splitting blasting with equal charge in different position by using the software ANSYS/LS-DYNA3D.With the condition of detonation to the initiation,and the location of the air layer is between two charges,the results of pre-splitting will to be perfect.(2) Pre-splitting blasting of axially uncoupling charge was numerically simulated by ANSYS/LS-DYNA3D to find the optimal parameters for controlled blasting technology. The outcomes show that the ideal axially uncoupling coefficients was2.16,matched with charge structure of air-deck.(3)Simulations were carried out to reproduce the variable effect of blasthole distance.pre-splitting blasting and attempts of controlling this impact were also made. The results indicate that using the air-separated charge structure with blasthole volume uncoupling coefficient being2.16could produce rock with proper blasting blocks.and ANSYS/LS-DYNA3D was employed to simulate5different charging forms in side holes, while keeping the loading dose constant, for the sake of optimizing the charging way. The researching results demonstrate that a good explosives distribution generated slighter damages to the filling bodies. Additionally, the blasting energy scattered much well when when the blast-holes were charged by air-separation, which could suppress blasting vibration with high efficiency. It was reasonable and advisable to charge the side holes by setting the uncoupling coefficient of2.16,with the blasthole distance was70cm.