Influence of Karst cave's position on wall rock long-term stability of tunnel

摘要

Karst cave is aimportant problem for the construction. This paper performs numerical analysis of influence of Karst cave's position on wall rock of the tunnel by using the RFPA software. The results show that with respect to different form of distribution, when comparing the effect to the stability of surrounding rock, the largest one is then side cave, then the bottom cave, die smallest is the top cave. The destroying domino effect area is mainly concentrated on the area beside the plane and the bottom of the cave, while top cave has relatively weaker effect to surrounding rock. Furthermore, the side cave often leads to transfixion failure.