Abstract：Kiaochow Bay subsea tunnel is the second self-building tunnel in China with the designed service life over 100 years. On the basis of service environment of subsea tunnel concrete，the durability experiments of concretes are conducted and concretes are compared with those of other major engineering cases. The prediction modeling of service life considering concrete carbonation，initial chloride contents and chloride diffusion in concretes is proposed. Considering the requirement of 100 years service life of subsea tunnel，the modeling parameters are calculated according to prediction modeling of service life. The results show that cover thickness of lining concrete，which faces to atmosphere，should be more than 70 mm and those of other sides should be more than 60 mm. The initial chloride concentration in concrete should be less than 0.15% of binding materials；and chloride diffusion coefficient of lining concrete must be less than 4×10－12 m2/s. Moreover，the water to binder ratio w/b of lining concrete should be less than 0.34 and strength grade higher than C50. Based on quantitative relationship between durability of concrete and mixture proportion，raw materials and the principle of mixture proportion designed as well as raw materials choice are given based on 100 years service life of subsea tunnel.
