关键词: 真三轴岩爆　自组织临界　声发射　幂律分布

Abstract: In order to explore the instability characteristics of granite rock burst under different stress states,the true triaxial single-faced empty rock burst test was carried out. Combined with the acoustic emission monitoring system,according to the self-organized criticality theory,the stress change during the rock burst process and the time attribute of the acoustic emission energy sequence and the spatial attribute of the positioning information were analyzed. The experimental results show that the self-organizing process of rockburst is decomposed into time line and space line,which realizes the visualization of self-organizing process of rockburst and the quantification of rock mass state to the greatest extent,and the energy time domain is verified by power law characteristics,which has strong self-similarity. The critical index of the second stage of rockburst is larger than that of the first stage,indicating that the probability of rockburst increases with the evolution of self-organization. The selforganization behavior of rock burst has the effect of intermediate principal stress. With the increase of intermediate principal stress,the limiting effect on rock fracture is enhanced. The later the critical point appears,the larger the critical index is. At the same time,the quiet period from sub-critical point to critical point under high intermediate principal stress is longer,and the self-organization behavior is weaker. It is easy to induce sudden and destructive rock burst disasters,and the difficulty of prediction is increased. The results of this study provide a more advanced and perfect idea for accurately predicting rock burst.

Key words: true triaxial rock burst,self-organized critical state,acoustic emission,power-law distribution