Characteristics and dominant controlling factors of gas outburst in Huaibei coalfield and its countermeasures

In order to master the main characteristics and controlling factors of gas disasters in Huaibei coalfield, based on data analysis, experimental determination and theoretical research, we analyzed the geological evolution and gas parameters in Huaibei mining area. The results show that Huaibei coalfield is located in Xu-Su arcuate tectonic circle, and the coal seam and gas occurrence took on bipolar-distribution. The dominant controlling factors of gas outburst were tectonic structures, tectonic stress, magma intrusion and mining depth. The geological conditions of Huaibei coalfield were very complicated, and almost all the outburst accidents occurred in tectonic structure zones. The horizontal tectonic stress played a dominant role in outburst accident. The thermal evolution and trap effect of magma intrusion controlled the physical characteristics of coal, gas occurrence and outburst. With the increase of mining depth, the possibility of gas outburst accidents increased significantly. After carrying out several effective regional measurements, the gas control effect was obvious and could ensure safety and high efficiency mining in outburst coal seams.