Precursor characteristics of acoustic emission electromagnetic radiation and gas and comprehensive early warning of outburst risk in driving face

In view of the current coal and gas outburst static early warning methods, the early warning indicators are single and discontinuous, and the critical value method adopted by the dynamic early warning method is prone to false alarms.By analyzing the precursor characteristics of the dynamic manifestation event of No.11227 transportation lane of Jinjia Coal Mine, the trend early warning method is used as a method for early warning of acoustic emission(AE) intensity, electromagnetic radiation(EMR) intensity, gas concentration, and the critical values of the warning parameters related to the trend of AE intensity, EMR intensity and gas concentration are determined. On this basis, according to the early warning results of AE intensity, EMR intensity and gas concentration index, the weights of each indicator were determined by analytic hierarchy process, and the comprehensive early warning criterion for acoustic electricity was proposed. Through on-site application and analysis,the results show that the AE EMR and gas comprehensive warning method can continuously and timely monitor and warn the outstanding danger of the driving face, the comprehensive early warning accuracy rate is 92.7%, the underreport rate is 0, and the false alarm rate is 7.3%, the reliability of the warning are high. It has important guiding significance for the prevention of coal and gas outburst to ensure safe production.