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| Research progress and comprehensive quantitative evaluation index of coal rock bursting liability |
| JU Wenjun1，2，LU Zhiguo1，2，3，GAO Fuqiang1，2，3，ZHAO Yixin4，LI Wenzhou1，2， SUN Zhuoyue1，2，HAO Xianjie4 |
(1. Coal Mining and Designing Branch，China Coal Research Institute，Beijing 100013，China；2. Coal Mining Research Institute Co.，Ltd. of CCTEG，Beijing 100013，China；3. State Key Laboratory of Coal Mining and Clean Utilization，Beijing 100013，China；4. School of Energy and Mining Engineering，China University of Mining and Technology(Beijing)，Beijing 100083，China)
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Abstract Through investigation and analysis of production conditions of rock burst mines in China，it is found that complex geological conditions and isolated working faces are the areas with high occurrence frequency of rock burst，although rock burst often occurs in shallow buried，near horizontal，thin coal seam and non-structural areas as well. Almost all coal seams in rock burst mines have a burst liability，which indicates that burst liability is the internal cause of rock burst，therefore accurate evaluation of the bursting liability is the basis of coal bump risk assessment. This paper systematically summarizes the research progress of qualitative analysis and quantitative evaluation of coal burst liability，discusses the scientificity of the existing evaluation methods of coal burst liability and the corresponding theoretical and technical problems，and puts forward a comprehensive evaluation index which includes the strength，stress and energy evolution and dynamic failure time. The research results of qualitative analysis show that the content，distribution and primary defects of different mineral components in coal rock materials affect the macro deformation and failure behavior，and then determine the impact propensity. The characteristics of acoustic，thermal，electrical and magnetic signals released by coal and rock mass with different impact tendencies are significantly different，and water，temperature，specimen size and loading mode directly affect the test results of coal rock impact tendency. The progresses of five types of evaluation indexes of the bursting liability including strength index，time index，stiffness index，deformation index and energy index are summarized，and their scientificity and defects are discussed. Based on the linear relationship between the stress state and the elastic strain energy accumulation，the elastic energy accumulation at the peak strength is calculated，the comprehensive evaluation index considering the strength，stress and energy evolution and dynamic failure time is established，and the corresponding classification critical value is proposed.
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2021, Vol. 40 
