Outburst prediction in Ji 4# mining district in Pingdingshan No.5 mine based on force and energy analysis

According to the prediction data of gas content and gas pressure of Ji 15# coal seam of Pingdingshan No.5 mine, from the view of force and energy, the influence of ground stress and gas as well as coal strength on coal and gas outburst is analyzed. It is found that under action of ground stress, elastic potential energy is much higher than gas expansion energy in the seam in Ji 4# mining district, i.e., ground stress mainly composed of tectonic stress is the major factor influencing outburst. In combination with the geological factors in the district and gas desorption of the seam, it is determined that the bottom index for coal and gas outburst risk area is gas content 5.4 m³/t in raw coal, or the absolute gas pressure is 0.79 MPa.The bottom index corresponds to the seam floor of elevation -600 m. Therefore the areas above-600 m do not have outburst risk and there exist outburst risk below -600 m. The study results guide effectively the gas control in the coal mine.