Study on the influence of gas pressure on the propagation of coal and gas outburst shock wave

In order to study the influence of gas pressure on the propagation of coal and gas outburst shock wave, a set of coal-gas two-phase flow simulation experimental system was developed independently. The simulation experiments of coal-gas two-phase migration law under different gas pressure conditions were carried out, and the visual monitoring of coal-gas two-phase migration in the roadway during the outburst process was realized. The experimental results show that the coal and gas outburst is a dynamic process from the outburst to the interior of the coal mass, the gas pressure fluctuates up and down for many times during the period; during the outburst process, the overpressure of the shock wave in the roadway presents a pattern of alternating change positive pressure and negative pressure, and the characteristic value of shock wave overpressure increases with the increase of the initial gas pressure in a logarithmic function; the propagation of shock wave overpressure in the roadway is a process of constant attenuation. The attenuation is slow in the early stage and accelerates in the later stage.