The effect of chloride binding on the predicted service life of RC pipe piles exposed to marine environments

• The effect of chloride binding on service life of RC pipe piles is investigated.
• The service life of RC pipe pile is dependent on the chloride binding capacity.
• Increasing chloride binding will increase service life of RC pipe piles.
• Chloride binding has a greater effect on service life in submerged zone.
• RC pipe piles display longer service life in submerged zone.

Chloride binding capacity has a significant effect on the service life of reinforced concrete (RC) pipe piles exposed to marine environments. Four typical chloride binding isotherms (i.e., null, linear, Langmuir and Freundlich binding isotherms) were reviewed in this paper. The effect of chloride binding on service life predictions of RC pipe piles, in terms of these different binding isotherms, was investigated. An experimental program was conducted to verify the theoretical predictions developed in the present study. The free and total chloride concentration profiles were presented for RC pipe piles exposed to submerged and splash zones for 5, 10 and 30 years. Furthermore, the predicted service life of RC pipe piles exposed to submerged and splash zones, using different binding isotherms, was also presented in this paper. The results of the present study indicated that the chloride binding has a more significant effect on the service life of RC pipe piles in submerged zone than in splash zone, and RC pipe piles in submerged zone display longer service life than those in splash zone.