Abstract:Due to the particular and complex engineering environment of subsea tunnel,the long-term structural health monitoring should be adopted to ensure the operation security of subsea tunnel. At the same time,stress change state of tunnel in complex environment will be realized. Then the damage position and damage degree of tunnel structure will be known in time for evaluating structure safety and disposing it effectively. For Xiamen Xiang¢an subsea tunnel,based on the present state generalization of tunnel structure health monitoring and characteristic of subsea tunnel engineering,the monitoring contents and important monitoring sites should be determined firstly according to necessary numerical simulation. Secondly,according to the practical situation of engineering,monitoring section positions,monitoring items and monitoring instruments will be selected. Besides,the following conclusions can be drawn. (1) To monitor the safety of tunnel in unfavorable geological area,except for the important site of tunnel,the auxiliary monitoring section should be also set up in adjacent and preferable geological conditions. Then it is very convenient to analyze the influence of unfavorable geological conditions on tunnel structure. (2) The leakage situation of subsea tunnel structure could be obtained by indirect monitoring results in main areas,such as arch lining cooperating change of lining water pressure in corresponding position. Issues mentioned above may have a guiding sense to the application of structural health monitoring of subsea tunnels under construction in China.