Closed-form solutions for bilinear surface chloride functions applied to concrete exposed to deicing salts

This study proposes new closed-form solutions for a mixed form of linearly increasing and constant surface chloride functions to remedy the inconsistency in predicting chloride diffusion in a previous study. The inconsistency occurs due to treating diffusion coefficient by using two redundant factors. To remedy the consistency, this study proposes to treat surface chloride by including a superposition term in the proposed solutions. To show the applicability, three examples are studied. The predictions of chloride diffusion in concrete by the proposed solutions are found consistent. To ensure the generality, the predictions by the proposed solutions are compared to those by the finite difference approach. From field data of concrete exposed to deicing salts, two bilinear surface chloride functions are compared for showing the importance of selecting an appropriate function. The sensitivity analysis reveals high influence of each parameter in the proposed solutions. The limitations of the proposed solutions are discussed.