Abstract: The development of the deviator stress induced tunnel hazards could be closely related to the hydrological conditions, design parameters and construction techniques. However, the most important factor that contributing to the tunnel hazards is the magnitude of the deviator stress. Under the sustained high magnitude of the deviator stress, the confining rock mass might develop a progressive failure mode and then induce various related hazards. Therefore, the mechanism of the deviator stress induced tunnel hazards have a special importance. In this paper, in addition to the numerical analysis results, the statistical analysis of the observed tunnel hazard data before and after the tunnel excavation are also conducted. The results indicate that, a tunnel under the high magnitude of deviator stresses might result in creep failure at the stress concentrated area in the lining system. As a result, cracks might be developed in the lining system and the seepage hazards might be induced.

Key words: Tunnel under Deviator Stresses, Hazards, Progressive Failures, Cracks, Water Seepage