Coal and gas outbursts in coal mines are a complex dynamic geological phenomenon. A gray target model has been established based on the gray system theory to predict coal and gas outbursts. The model considers four influencing factors for coal and gas outbursts: gas pressure, destructive type of coal, coal rigidity, and initial speed of methane diffusion. Each weight of the factors is given through an improved analytic hierarchy process without consistency checks, and the accuracy of the assessment is high. By using the model, coal and gas outbursts in the Jinzhushan mine were predicted. Results demonstrate the viability of the gray target model in the prediction of coal and gas outbursts.
Coal and gas outburst, gray target model, prediction, relational degree
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