Theoretical evaluation of diffusion coefficient of chloride ion in mortar from mobility

Many researchers have been trying to evaluate the diffusion coefficient of chloride ion in concrete by using quantitative and qualitative electromigra tion tests. Up to now, however; there has been no sufficient method to clos ely determine the diffusion coefficient of chloride ion through electromigr ation tests. In this paper; the diffusion coefficient of chloride ion in mo rtar by mobility is investigated through an electromigration test. Basicall y, the concept of Einstein's equation, which can relate the diffusion coeff icient of the chloride ion and the mobility in an ideal solution (with very low concentration), is adapted. Then, for compensating the influence of th e concentrations, the Debye-Huckel theory is used. Also, for considering th e effect of other existing ions, namely OH-, Na+, and K+, the electrical ne utrality is taken into account. Therefore, using Einstein's equation, the D ebye-Huckel theory, and electrical neutrality, the diffusion coefficient of chloride ion can be calculated theoretically from the mobility. The correc tness of the calculation is checked by a series of tests.