Experimental and simulation study on chloride permeability in cement paste

Abstract

A rapid chloride migration test (RCM) was used to measure the chloride diffusion coefficient of cement-based materials. A semi-empirical formula for chloride diffusion coefficient including water-cement ratio and curing age parameters was developed, which can be used to predict the variation of the chloride diffusion coefficient in the later stage. Finally, using the COMSOL finite element software and the parameters obtained in the experiment, the chloride diffusion process of the sample was simulated. The penetration depths of chloride ions at different water-cement ratios were obtained, and they were in good agreement with the experimental values, with deviations less than 10%. Through the simulation, we can clearly see that the concentration distribution of chloride ions and the depth of penetration depth decrease with increasing water-cement ratio, and increase with age.