Abstract: During the construction process of fractured rock structure in tunnel, the geological disasters such as large volume of collapse, incremental instability of surrounding rock and huge rock fall occur constantly. Although the survey technologies, theoretical models, numerical methods and the evaluation system of tunnel engineering emerge in endlessly in recent years, the reliability calculation of surrounding rock stability for tunnel and underground engineering has not been solved exactly. The serious difference between complex geological system and mechanical model becomes "the bottleneck" of deterministic analysis methods. Besides, one single analysis method or deterministic calculation cannot obtain steady evaluation results either. Unlike pure structural engineering, which has a comparatively clear mathematical model, the most significant character for underground rock mass engineering construction is the uncertainty of surrounding rock structure. In this paper, the uncertainty, which can be seen as the fundamental attributes of rock mass structure, is taken into full account. The research status and existing problems are systematic summarized, especially for the image acquisition and multiple interpretation of fractured rock mass, stable reliability analysis of surrounding rock and local key blocks and intelligent feedback and system evaluation of tunnel engineering. Moreover, the corresponding countermeasures and development tendency are also explored and proposed.

Key words: tunnel, fractured rock structure, surrounding rock stable reliability, fractured rock structure uncertainty