Abstract:Xiamen Xiang¢an subsea tunnel is the first subsea tunnel in mainland China,the length of which is 6 051 m. The length of the part of Xiamen Xiang¢an subsea tunnel in shallow beach is 610 m. There are no similar projects and experiences of construction for subsea tunnel to be referred. So the construction is difficult for the tunnel in shallow beach across the water-enriched sandy stratum. The key construction techniques for the tunnel across the water-enriched sandy stratum in shallow beach are introduced. The diaphragm wall and decompression well are used to resist and drain groundwater of sandy stratum. The ductule pre-grouting technology is used to reinforce sandy stratum in the tunnel. Integration of outside and inside construction technology of tunnel is adopted to cross the water-enriched sandy stratum in shallow beach. The practical result shows that the construction techniques are convenient and effective. The construction experiences are useful references to other underground engineering under similar geological conditions.