Modification of chloride diffusion coefficient of concrete based on the electrical conductivity of pore solution

To correct the influence of pore solution on the chloride diffusion coefficient and set up a comparable permeability test method with other penetration experiments based on rapid chloride migration (RCM), the influence of supplementary cementitious materials (SCMs), including grounded granulated blast furnace slag (GBFS) and fly ash (FA), on the electrical conductivity of pore solution was investigated. A modification method of chloride diffusion coefficient was proposed based on the relationship between the electrical conductivity of pore solution and chloride diffusion coefficient. It was found that the modified chloride diffusion coefficients of the same mortars with differential solution by replacing the original pore solution with NaOH solution were almost identical. The modified relative chloride diffusion coefficients of concrete with differential SCM were close to the relative water absorption content. Results indicating that the modified chloride diffusion coefficient eliminates the effect of electrical conductivity of pore solution and could reflects transport property of concrete due to the connectivity pore, thus can be used to evaluate the generally permeability of concrete.