Abstract
Abstract Water is one of the key elements influencing the course of gas-dynamic processes in coal seams; therefore, methods related to water injection are used for coal and gas outburst prevention. However, there are still many problems associated with the use of injection technologies and with the determination of their parameters. In this work, a mathematical model of elastic-plastic deformation of a coal seam and two-phase fluid filtration during hydraulic extrusion was developed. Numerical simulation of time changes in geomechanical and filtration parameters during coal seam hydraulic extrusion was performed, and the distributions of these parameters at different time points were presented. It is shown that zones of inelastic deformations are formed around the filtering parts of the holes. Gradually, the area of hydraulic influence expands, water comes to the coal surface and the mine face displaces into the roadway. After the injection is completed, the processes of redistribution of the stress field and coal seam deformation slow down and return to the quasi-stationary regime. Hydraulic extrusion as a measure of reducing the risk of coal and gas outbursts requires a reasonable approach to the selection of its implementation parameters, for which the developed numerical model can be used.