Study On Improvement Of Identification Index System Of Coal And Gas Outburst Mine

The method of single parameter for the outburst risk identification of coal and gas outburst is still not perfected, which has been used in China for serveral years. The wrong results are often found sometimes, and bring great hidden danger to safety in coal mine. In view of the problems existing in the single index method, based on the mechanism of coal and gas outburst, this paper clarified the evolution of coal and gas outburst and the conditions of occurrence, and established the mechanical model of the working face, and got the main physical quantity of controlling the coal and gas outburst at last.The variables in the process of coal and gas outburst are changed into non dimensional parameters by using the dimensional analysis. Based on identification and prediction index existing for outburst, these non dimensionless parameters are analyzed, a series of combined physical quantities and the key dimensionless parameters are constructed, a new appraisal index system of coal and gas outburst are build as a result. According to the background of the new index, the relationship between the indexes are given. With reference to the existing research results, the new index system is suppled. Finally, the accurracy of the index system is tested by using the numerical simulation according to the case of outburst accident.The improved index system will be able to show the inner relationship bettwen the main factors which control coal and gas outburst, the impact of crustal stress, and geological anomaly on the outburst dangerous. The non-dimensional characteristic of the index ensures that it has a wide range of applicability to the majority of mining conditions, and a higher accuracy rate of identification, comparing to the current single parameter method.