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Abstract Based on summarizing the main results and theoretical methods of rockburst vulnerability evaluation，the development process and basic framework of a new rockburst vulnerability evaluation method for deep tunnels are put forward. The 62 rockburst cases which occurred in deep tunnels of Jinping II hydropower station are analyzed；and the characteristics and main controlling factors of rockburst are revealed. New empirical assessing index—rockburst vulnerability index(RVI) and its established methods are both proposed；while the principle of selecting controlling factors is confirmed. RVI is constituted by four controlling factors，namely stress control factor Fs，rock petrophysical factor Fr，rockmass system stiffness factor Fm and geologic structure factor Fg，which respectively reflect different contributions of rockburst controlling factors to rockburst vulnerability. It is found that there is a significant correlation between the failure depth of rockburst and RVI. An empirical equation is established and its determination coefficient is more than 80%. The empirical equation can be used for evaluating the rockburt vulnerability and its damage level. The applicability of RVI method is verified through the analysis of representative rockburst cases which occurred in deep tunnels of Jinping II hydropower station.
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Received: 23 December 2010
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2011, Vol. 30 
