Behavior of apparent chloride diffusion coefficient of fly ash concrete under long-term marine exposure

In this study, outdoor exposure tests were performed for fly ash concrete considering long-term marine exposures and mix conditions. Different fly ash substitution ratios, water-binder ratios, regional exposure conditions, and exposure periods were considered. As the exposure period increased, the effect of the water.binder ratio on the apparent chloride diffusion coefficient decreased due to reduced chloride ingress. The increase in the diffusion coefficient with the water.binder ratio in concrete with ordinary portland cement was higher than that in fly ash concrete cement. Relationships between the apparent diffusion coefficient and RCPT (Rapid Chloride Penetration Test: passed ion charge) based on mix proportions were proposed with three regional exposure conditions.