Sensitivity study and application of prediction indicators for coal and gas outburst risk in Yuxi coal mining faces

Abstract

To reasonably determine the sensitive indicators for predicting coal and gas outburst hazards in mining faces, this study employs mathematical modeling to process measured drill cuttings gas desorption data through dimensionless and standardized treatment, calculating their sensitivity functions and identifying their sensitivity. The results indicate that among the three indicators used for outburst prediction, the drill cuttings gas desorption index K1 is more sensitive than the drill cuttings gas desorption index Δh2 and the drill cuttings volume S. Thus, K1 can serve as the sensitive indicator for predicting coal and gas outburst hazards in this mining face. When the K1 value exceeds the internal control threshold of 0.4 mL/(g·min^1/2), abnormal phenomena such as borehole spraying, bit jamming, abnormal gas emission from drill holes, or coal burst sounds may occur during drilling, and the more significant the K1 value, the more pronounced the dynamic effects. Comparative analysis of field test data shows that the mathematical model's analysis results are largely consistent with actual observations, ultimately confirming the drill cuttings gas desorption sensitive indicator for the test area. Through practical application of the sensitive indicator for coal and gas outburst hazard prediction in the 1306 mining face of a certain mine, favorable outcomes were achieved.