Ceramics-Silikáty 68, (3) 342 - 352 (2024)

In this paper, a chloride diffusion model of coral aggregate concrete under an extremely hot and humid marine environment was studied, and nine mix ratios of coral aggregate concrete were analysed and researched. Utilising Fick's second law, a chloride diffusion model for coral aggregate concrete was established. It considers the impact of the temperature, humidity, erosion time, compressive strength of coral aggregate concrete, fly ash content, and basalt fibre content on the chloride diffusion coefficient in the extremely hot and humid marine environment of the South China Sea. Furthermore, the impact of sulfate ions on the chloride diffusion was considered, and the degree of damage to the coral aggregate concrete was defined. A relationship between the relative chloride diffusion coefficient and the degree of concrete damage was established, thereby successfully incorporating sulfate erosion damage into the chloride diffusion model. Finally, an analysis was conducted on the values of the parameters in the diffusion model. The established chloride diffusion model was used to calculate the chloride concentration distribution under different erosion environments, and the experimental values were compared and analysed to verify the accuracy of the diffusion model. The results show that the calculated results are in good agreement with the experimental results. The establishment of the model can provide a theoretical basis for the durability design and life prediction of coral aggregate concrete under extremely hot and humid marine environments.