| Abstract: | Based on seawater immersion, drying-wetting cycles, carbonation and drying-wetting cycles for coral aggregate sea-water concrete (CASC) with different strength grades, the effect of carbonation and drying-wetting cycles on chloride diffusion be-havior of CASC is studied. The results show that the free surface chloride concentration (Cs), free chloride diffusion coefficient (Df) and time-dependent index (m) of CASC in the drying-wetting cycles is obviously higher than that in seawater immersion. The Df and m of CASC of carbonation and drying-wetting cycles is higher than that in the drying-wetting cycles. Carbonation increases the Df and m of CASC, which is against CASC to resist chloride corrosion. The corrosion possibility of CASC structures in different ex-posed areas is as follows: splash zone (carbonation and drying-wetting cycles) > tidal zone (drying-wetting cycles) > underwater zone (seawater immersion). Besides, the chloride diffusion rate of C65-CASC is 17.8％ – 63.4％ higher than that of C65-ordinary aggre-gate concrete (OAC) in seawater immersion (underwater zone). Therefore, anti-corrosion measures should be adopted to improve the service life of CASC structure in the oceanic environment. |
