Abstract: Cavern tunnel diseases, mostly forming underground stress field under the action of damage, seepage, temperature and other factors, are very complicated nonlinear coupling process. In this paper, the author employs the stimulate- response coupling system being made up of Bui damage model and seepage field, the result shows that the diseases will form obviously when the coupling strength factor is about 0.5, with the cranny expanding and the damage increasing in the surrounding rock, the plastic Radius of underground rock is increasing with the porous hydraulic pressure, it speeds up the appearance of tunnel diseases. It has some positive significance to prove up the coupling mechanism, the repair and the the protection of the cavern tunnel.

Key words: cavern tunnel, disease, nonlinear coupling, seepage