According to the geological section of the Xiangshan Harbour subsea tunnel
the tunnel axes of nine sections selected are researched and analysed. The appropriate tunnel axis of each section is fixed on through lifting and shifting the tunnel axis according to the thickness of bedrock. The paper applies the finite element program of fracture damage model to analyze different cases of the sections. Analyzing their damage zones
plastic zones
stress state and displacement variation in all the cases
the stability of the tunnel is studied. Based on the above analysis
the most appropriate tunnel axis position of every section is proposed.