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The mechanism of blasting failure of coal is considered for which a combined model of gas-saturated coal is used, which describes the relationship between explosive damage to the coal seam and the subsequent emission of gas. Based on this model, the numerical method of Smoothed-particle hydrodynamics (SPH) is studied the development of zones of failure and stress-strain state of the seam at the vicinity of the well charge after the explosion. In better patterns, help predict coal reaction to explosive dynamic impact. This may be considerable interest for the development of the technology of preliminary degassing coal seams, as well as the theoretical description of the processes occurring in the occurrence of carbon and gas emissions. In this regard, the mechanism for the preparation of gas-producing failure of the packing of the thrust ("bend") of coal with an explosive impact on the coal seam is considered. The investigation includes the study of the formation of cracks in the far from the explosive well zone, modeling the filling of induced cracks of the methane, which is initially in an coal in solvent state, and the time estimate of the initial development of the induced cracks due to the pressure of free methane in the crack. It is established, what depending on the mechanical and diffusion parameters of coal, the start time of the development of the fracture may vary from some tens seconds to many hours. The results of the study may be useful in the development of the theory of explosive effects on the coal seam used in practice in the combination of measures to reduce the risk of sudden outbrust of coal and gas. [ABSTRACT FROM AUTHOR]

To solve an urgent problem in the coal industry - forecasting emergency hazardous phenomena in mine workings, taking into account the geodynamic activity of the coal seam, it is advisable to represent such a coal seam in the form of some energy-saturated medium, capable of collapsing under certain conditions and releasing a significant amount of kinetic energy into the array. Based on the results of computer calculations for a particular scheme of drilling and blasting operations, it is possible to identify the moment and place of the outburst origin and evaluate the consequences of filling the working space with crushed coal masses and methane. The paper proposes a new model for modeling the entire ejection process. The model integrates well-developed numerical approaches: the finite element method and Euler solver and the Smoothed Particle Hydrodynamics (SPH) method. The first explicitly simulates the deformation, destruction and destruction of a solid, and the second simulates the flows of an ejected mixture of coal, rock and gases, the third is convenient for simulating explosive charges. The interaction and behavior of geomaterials with different physical and mechanical properties in a coupled model under dynamic loading are illustrated. A simple example is presented to simulate a coal and gas outburst process to demonstrate the potential of a coupled model. The results obtained for various parameters of energy saturation can be applied to the study of the regularities of the occurrence and course of the outburst phenomena. At the same time, the capabilities of the SPH method were tested as part of a combined computational approach for computer calculation of the stress-strain state of a coal-bearing rock mass, taking into account the possibility of an outburst. The main task was to obtain adequate results of the consequences of drilling and blasting operations in a rock mass near an outburst-hazardous coal seam. [ABSTRACT FROM AUTHOR]