煤的冲击倾向性研究进展及冲击地压“人-煤-环”三要素机理

Research progress of coal bursting liability indices and coal burst“Human-Coal-Environment”three elements mechanism

煤的冲击倾向性是冲击地压机理的基础研究问题之一,也是目前评估和预测煤矿冲击地压危险程度的主要依据之一。系统梳理了煤的冲击倾向性专业术语和冲击倾向性指数的研究历史,提出了煤的冲击倾向性直接指数和间接指数的概念和定义。对现有的16种冲击倾向性指数的出处、定义、表征符号、计算公式、试验过程、分类标准等进行了详细介绍。对来自5个煤矿的30个煤样进行了单轴压缩试验,利用试验结果对16种冲击倾向性指数进行了计算,获得了具体的冲击倾向性类别。为了对煤的16种冲击倾向性指数的判别结果进行统一验证,根据煤样破坏过程和破坏状态,提出了基于试验现象的煤样冲击倾向性定性判据及分类标准。通过统一对比,结果表明剩余弹性能指数判别结果和定性判据判别结果完全一致。剩余弹性能指数以煤线性储能规律为基础,从煤样受力全过程中能量输入、储存、消耗、剩余的角度出发,以煤样破坏时剩余的绝对能量值作为判别指标,符合冲击地压发生时释放弹性应变能的本质。剩余弹性能指数属于煤的冲击倾向性直接指数,所得结果实现了和定性判别结果的相互验证和统一,具有科学性与适用性。根据冲击地压属于深部工程地质灾害的特点,借鉴系统工程学思想提出了冲击地压“人-煤-环”三要素机理,进一步明确了煤的冲击倾向性研究所起的作用和地位。从力学性质和材料性质2个方面分析了煤和岩石的本质属性差异,认为冲击地压属于固体可燃有机岩动力破坏,而岩爆属于固体不可燃无机岩动力破坏。最后,提出了煤的冲击倾向性指数研究中存在的6个关键科学问题。

The bursting liability of coal is one of the basic research problems of coal burst mechanisms,and it is also one of the main basis for evaluating and predicting the bursting risk degree of coal burst mine.This paper systematically summarizes the technical terms related to coal bursting liability,reviews the research history of bursting liability indices,and proposes the concepts of direct and indirect indices of coal bursting liability.The source,definition,characterization symbol,calculation formula,test procedure,and classification standard of 16 existing bursting liability indices are introduced in detail.Uniaxial compression tests are conducted on 30 specimens from five coal mines.The 16 bursting liability indices are calculated based on the test results and the specific bursting liability categories are obtained.To uniformly verify the discriminant results using the 16 bursting liability indices,a qualitative criterion and classification standard of coal bursting liability based on experimental phenomena are proposed according to specimens′failure process and post-failure behaviour.A comparison shows that the discriminant results of residual elastic energy index(C_(EF))are completely consistent with the qualitative criterion discriminant results.C_(EF) is established based on the linear energy storage law of coal,considers perspectives of energy input,storage,consumption and surplus in the whole loading process of coal specimens,and takes the absolute residual energy during coal specimen destruction as a discriminant index.Therefore,it conforms to the essence of releasing elastic strain energy when coal burst occurs.C_(EF) belongs to the direct index of coal bursting liability,and mutual verification and unification are realized between the obtained results and the qualitative judgments,which is scientific and applicable.According to the characteristics that coal burst belongs to deep engineering geological disaster and drawing on the idea of system engineering,the three elements mechanism of“Human-Coal-Environment”of coal burst is put forward,which further clarifies the role and status of the research of coal bursting liability.The essential properties of coal and rock are analyzed from two aspects of mechanical properties and material properties.Coal burst belongs to the dynamic failure of solid combustible organic rock,while rockburst belongs to the dynamic failure of solid non-flammable inorganic rock.Finally,six key scientific problems of coal bursting liability index are put forward.