组合煤岩破坏过程能量耗散特征及冲击危险评价

为揭示组合煤岩失稳破坏过程中的能量耗散规律，通过组合煤岩单轴压缩试验，从能量角度对组合煤岩失稳特征进行了分析。引入分形理论，研究了声发射信号与煤岩破坏程度之间的关系，以及不同组合结构对组合煤岩破坏过程的能量耗散的影响，提出一种利用煤岩结构力学特性判定冲击危险的方法。结果表明：随组合煤岩顶板岩石高度增加，试样整体强度和弹性模量增加，峰后应变软化过程缩短；岩石高度的增加，岩石与煤的弹性模量差值的减小均会导致冲击危险增加；通过对组合煤岩中岩石和煤的高度及其力学性质分析，提出了组合煤岩冲击倾向性判定指数，利用冲击倾向性判定指数对组合煤岩冲击危险进行评价，其准确度和实用性优于传统模糊判定的“四指标”方法，为深入开展煤岩组合结构冲击倾向评价提供了试验和理论支持。

Energy dissipation feature and rock burst risk assessment in coal-rock combinations

To explore the energy dissipation of coal-rock combinations failure, uniaxial compression experiments were conducted to investigate the failure process characteristics in terms of the energy. Meanwhile, the relationships of failure and acoustic emission signal were discussed based on fractal dimension. Method for evaluating the risk of rock burst was proposed, based on the investigation of the different combination structures influence on energy dissipation of coal-rock combination. The results show that when the rock height increases, the strength and elastic modulus increase, and the softening process decreases. The raise of rock height could increase the impact risk, as well as the reduction of difference between the elastic modulus of rock and coal. In addition, a new decision method was proposed based on the analyses of height and mechanical properties of coal-rock combination, compared with the “four index” of traditional fuzzy evaluation. The result of assessing the rock burst index by the decision method has higher accuracy and practicability. These results provide the data and theoretical support for further development study of rock burst risk in coal-rock combinations.