Analysis on Simulation Experiment of Outburst in Uncovering Coal Seam in Cross-cut

Based on the criteria of the Hoek-Brown rupture, the stress state of the coal's outburst is analyzed. The establishment of coal mining mechanical model and the critical pressure of the gas outburst are obtained on the basis of catastrophe theory, and then cross-cut outburst process of uncovering coal is classified as outburst breeding, outburst initiation, outburst development and outburst termination. Choosing Luling coal mine's #8 coal seam as a sample, this article relies on the large-scale three-dimensional coal and gas outburst experiment platform of the Key Laboratory of Mine Disaster Prevention and Control of Shandong University of Science and Technology to conduct cross-cut uncovering coal outburst simulation experiment. Through analysis of the surrounding rock stress and gas pressure experimental data, surrounding rock mechanical properties and the change situations when outburst happens in the process of uncovering coal are obtained. The experiments show that: when outburst occurs, the greater changes of crustal stress and gas pressure happen near the outburst mouth; and the stress and gas pressure in front of outburst mouth change significantly more than that at the rear of the mouth.