Study of the multi-index coupling forecasting model of coal and gas outburst and its application

Coal and gas outburst seriously threatens the safety of underground coal mining. With the increase in coal mining depth, the geological conditions of coal mines become complicated, which adversely affects the safety of coal mining production. Prominent prediction is an important link to reduce the damage caused by outburst accidents. This study investigated the prediction model of coal and gas outburst. On the basis of the analysis of the gas geological factors of coal and gas outburst, a prediction system including 3 major indices (i.e., gas, coal, and crustal stress indices) and 12 minor indices (e.g., gas pressure and tectonic coal thickness) was established. A multi-index coupling prediction model based on the improved input and output of the gray correlation model was proposed. Network analysis and multi-class distance discriminant method were also comprehensive applied to improve the accuracy of coal and gas outburst index prediction. On the basis of the comprehensive analysis of the gas geological factors of coal and gas outburst, the model calculates the weight of the prediction index, classifies the possible grade of the outburst, and derives the discriminant formulas to discriminate the possibility of outbursts. Taking the Pingdingshan No. 8 coal mine as an example, the model estimated the probability of coal and gas outburst in eight sets of prediction samples. The predicted results are consistent with the actual conditions, provide technical support for coal mine and gas outburst prevention, and prove the accuracy and applicability of the multi-index coupling prediction model.