Research on the mechanism of coal and gas outburst and the screening of prediction indices

Abstract

According to coal and gas outburst mechanisms, lab and field measurement, actual situations of Sihe coal mine and articles in Prevention Regulations of Coal and Gas Outburst, the relevancy among chief static indices of outburst prediction are analyzed. The static sensitivity index system is screened out to predict coal and gas outburst by multi-source information in Sihe, such as destruction type of coal, coal’s consistent coefficient, initial rate of methane diffusion, gas pressure, gas content, depth of coal seams, occurrence change of coal seams, geological structure, cuttings desorption index K1, etc. K1 has the characteristics of easy measurement, strong generalization, high reliability and accuracy. So K1 should be firstly chosen when a single index is adopted to predict outburst. The provision of article 34 in Prevention Regulations of Coal and Gas Outburst about the drilling holes’ diameter, depth and test contents for the same prediction method are different from article 38. These will lead to ambiguity in practical applications. The research shows that articles should be revised as follows: prediction drilling apertures should be determined by engineer drilling tool, and K1 of wet or dry cuttings each can be used as prediction index.