Due to the complex mechanism and numerous impact factors,and considering the existing differences among the impact factors of coal burst with various weights in different regions,a coal burst assessment model based on the methods of regional divisions and main impact factors recognition was proposed to improve the accuracy and relevance of the assessment results,which was then used to analyze coal face LW250204 in Yanbei Coal Mine.Due to the comprehensive effect of thick coal seam,fold structure,mining disturbance,seam dip angle,mining depth and mining complex geological factors,the working face was under severe threat of coal burst.The results show that:① The thickness,dip angle and depth of the coal seam have obvious influence on the rock burst hazard in local areas,and the distribution of mining tremors is strongly correlated with syncline and mining disturbance,and they dominate the rock burst hazard in their affected areas;② Based on the distribution range and the variation of each influencing factor,the working face is divided into five regions.According to the basic principle of the analytic hierarchy process (AHP),a weighting assessment system of influential factors of coal burst was constructed,and the weighting differences among factors was identified;③ For quantitatively describing the coal burst hazard level in an specific area of different regions,a regional coal burst hazard index was constructed.In LW250204,up to 92.6％ of the fitting degree was presented between the mining tremors distribution and the coal burst hazard indexes,which verifies the accuracy and reliability of the model.%冲击矿压机理复杂,影响因素众多,不同区域内冲击矿压影响因素种类及其权重往往存在差异.为提高冲击危险性评价的准确性与针对性,提出一种基于区域划分与主控因素辨识的冲击危险性评价方法.以砚北煤矿250204工作面为研究对象,该工作面受特厚煤层、褶曲构造、采掘干扰、煤层倾角、开采深度等因素综合影响,存在严重冲击矿压威胁.研究结果表明:①煤层厚度、倾角及开采深度仅在局部区域对冲击危险性存在明显影响;向斜构造及采掘干扰与矿震事件分布的相关性最为密切,对冲击危险性影响强烈;②依照各因素的影响范围与变化趋势,进行工作面区域划分,构建基于层次分析法(AHP)的冲击矿压影响因素权重评价体系,辨识各影响因素间的权重差异;③构建基于因素权重差异的冲击危险指数,定量描述区域内冲击危险程度.经检验,250204工作面整体冲击危险性指数分布与矿震定位拟合程度高达92.6％,证明了评价结果的准确性.
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