| Based on the theory of blasting mechanics and fracture mechanics and so on, the Controlled Pre-splitting Blasting against outburst Technology for outburst coal tunnel driving is studied in this paper by use of ANSYS / LS-DYNA computer simulation software, combined with on-site test verification, get the following beneficial results.(1) Based on classic blasting mechanics and fracture mechanics theory, this paper analysises the mechanism of shock wave, stress wave and blasting gas quasi-static stress field during the process of crack, also analysis the condition for the beginning, bifurcation and stop of blasting crack.(2) The ANSYS / LS-DYNA software is used in the paper for computer finite element simulation, in order to analysis the blasting stress wave propagation and the crack propagation under different conditions, such as different amount of dynamite, different blast hole spacing, different blast hole and control hole spacing. Then The optimum blasting parameters are obtained. At the same time, the blasting crack propagation under different sections and the coal seam roof and floor damage can be simulated in use of the optimum blasting parameters.(3) The on-site effect of controlled pre-splitting blasting technology against outburst is studied in the paper. The results indicate that by utilizing pre-splitting blasting measures can prevent the outburst effectively when driving through the course of coal tunnel, it's also can increase the seam permeability coefficient, thus can improve drainage drilling efficiency and reduce the coal gas content of the heading face, make the concentration stress region divert to the farther coal area, extend the length of pressure relief region and eventually achieve the purposes of rapid excavation.(4) The paper with the results from test on site shows that the computer simulation and on-site test results are basically the same. It proves that computer simulation can be used for pre-splitting blasting on-site guidance.
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