A quantitative evaluation method of coal burst hazard based on zone division and an analytic hierarchy process: a case study on Yanbei coal mine, Gansu Province, China

The occurrence of coal bursts affects the safety of coal mines while coal burst hazard evaluation exerts a guiding influence preventing future coal bursts. Therefore, a method for quantitatively evaluating coal burst hazard was proposed based on zone division and an analytic hierarchy process (AHP). On this basis, by considering the distribution of influence factors of coal bursts in coal mining face (CMF) and means of influencing weight changes, the research aimed to enhance the accuracy and pertinence of coal burst hazard evaluation. By investigating the LW250204 of Yanbei Coal Mine in Gansu Province, China, it can be speculated that the CMF was influenced by various factors (including extra-thick coal seam, syncline and anticline tectonics, mining- induced disturbance, dip angle of coal seams, and mining depth) and thus suffered significant threat of coal burst. The results revealed the following three points: firstly, the degree of coal burst hazard had a positive correlation with the thickness of the coal seams, the mining depth, and mining-induced disturbance, while it exhibited a negative correlation with syncline and anticline tectonics. Moreover, it showed a parabolic correlation with the dip angle of the coal seams. Secondly, the zone division of the CMF was carried out according to the range of influence and changes in various factors. Based on AHP and the degree of influence of different factors on coal burst hazard, an evaluation matrix for the weights of influence factors driving coal bursts was established to quantify the differences between weights of various influence factors. Thirdly, based on the evaluation matrix for weights of influence factors, the relative coal burst hazard index was constructed to quantify the coal burst hazard in a given zone. Through testing, the goodness of fit between the distribution of the global relative coal burst hazard indices of the LW250204 and mininginduced tremors (MITs), as located, reached 90.8%, which validated the accuracy of the evaluation results. The research can provide a reference for quantitative evaluation of coal burst hazard in coal mines.