(1. 长沙交通学院岩土研究所，长沙 410076; 2. 中南工业大学，长沙410083
3. 耒宜高速公路公司，郴州423000)
摘 要: 在应用断裂力学原理分析岩体裂隙扩展特点的基础上，分析讨论了岩爆发生机理，提出了隧道围岩应力强度因子等值线的概念，认为隧洞岩爆将沿该应力强度因子等值线KⅡθ=KⅡC圈定的范围崩落，岩体裂隙失稳扩展导致隧洞岩爆的必要条件为同时满足裂纹开裂判据KⅡ=KⅡC及裂纹失稳扩展判据k+f'(δ)＜0，并指出同时满足这两个条件的岩体裂隙有临界开裂和临界止裂两个长度。
关键字: 岩爆机理；断裂力学；预测方法
（1. Geotech. Eng. Inst, Changsha Comunications University, Changsha 410076, P. R. China
2. Central South University of Technology, Changsha 410083, P. R. China
3. Leiyi Highway Construction Company, Chenzhou 423000, P. R. China）
Abstract:Based on the analysis for crack propagation in rockmass, the rock burst mechanism was analysed and the concept of stress intensity isogram for cavern's surrounding rockmass was proposed. The rock burst limits will be enclosed by this stress intensity isogram. The essential conditions for rock burst which caused by unstable crack propagation was simultaneously satisfied crack propagation criterion KⅡθ=KⅡC and unstable crack propagation criterion k+f'(δ)<0. The cracks which simultaneously satisfied these criteria exist critical initial fracture length and critical stop fracture length.
Key words: rock burst mechanism; fracture mechanics; predictions method
