Nondestructive Method for Estimation of Chloride Profiles: Correlation between Electrical Resistivity and Holliday-Empirical Equation

Abstract

Concrete electrical resistivity has been performed as a durability parameter because this is a nondestructive, simple, fast, and reliable technique for evaluation of reinforced concrete field structures. The results obtained have been used mainly to verify the probable reinforcement corrosion risk. However, other applications for electrical resistivity are possible, such as service life estimation of concrete structures in a marine environment. This paper presents the applicability of concrete electrical resistivity as a parameter for the determination of modified Holliday equation variables for chloride profile modeling of field reinforced concrete structures present in a marine environment. For this, chloride profiles of reinforced concrete structures present for more than 40 years in different marine aggressive zones were analyzed. The results showed that all the modified Holliday equation variables can be estimated by electrical resistivity values presenting moderate to very high statistical correlations. The chloride concentration peak was observed near the concrete surface for concretes that presented lower electrical resistivity. Concretes that presented low electrical resistivity showed high chloride concentrations in the profiles, including concentrations up to 1.6% by concrete mass at the peak.