Numerical Simulation Research on Coal-Gas Outburst in the Process of Development

Coal-gas outburst is a kind of complex disaster induced by engineer operations in the process of extracting or developing in coal seams. According to the theories of gas seepage and deformation of coal or rock seams, taking consideration of the heterogeneity property of coal or rock materials in mechanics of materials as well as non-linear permeability characteristic of coal or rock materials in the process of deformation and fracture, SPH algorithm of LS-DYNA software is used to numerically simulate the coal-gas outburst induced by development in coal seams. Simulation results represent the whole process of coal-gas outburst from the growing, extending and connecting of cracks to final outburst under the impact of gas pressure, ground stress and mechanical properties of coal-rock. The nonlinear nature of the mutation of outburst induced by gradual destruction of the coal or rock materials under the influence of developing operations is revealed, including the evolution of the stress field in the rupture process of the coal or rock material. This provides a theoretical foundation for further understanding the mechanism of coal-gas outburst as well as preventing outburst technology.