Service life prediction of marine concrete structures

Abstract

Reliable durability design of marine concrete structures requires a critical understanding of the chloride diffusion in unsaturated concrete. A mathematical model for predicting the relative chloride diffusion coefficient has been established in a previous work [1]. In the present paper, that model will be extended to analyze the time-dependent chloride diffusion coefficient in unsaturated cementitious materials. The role of the degree of water saturation in service life prediction is discussed. It is emphasized that the long-term sharp decrease of the chloride diffusion coefficient in marine concrete is not primarily caused by densification of the microstructure, but by the decreasing degree of water saturation.