Revisited to the relationship between the free and total chloride diffusivity in concrete

Abstract

The main purpose of this paper is provided the theoretical elucidation and parameter investigation for the experimental results performed by Lu et al. [Relationship between the free and total chloride diffusivity in concrete, Cement and Concrete Research, 32(2) 323-326 (2002)]. The analytical solution of Fick's second law of linear diffusion in a semi-infinite quasi-homogeneous and isotropic concrete with initial and boundary conditions is used to curve fitting the experimental results and to find the relevant parameters such as the total and free chloride concentrations and diffusivities. The total chloride diffusivity is 2.8 times the free one. It seems plausible to assume that bound chloride content in concrete is about two times that of the free one.