Corrosion rate measurement by using polarization resistance method for microcell and macrocell corrosion: Theoretical analysis and experimental work with simulated concrete pore solution. (18th January 2021)

• Record Type: Journal Article
• Authors: Chen, Lijie; Su, Ray Kai Leung
• Is Part Of: Construction & building materials. Volume 267(2021)
• Publication Date: 2021-01-18
• Subjects: Reinforcement corrosion -- Corrosion rate -- Macrocell corrosion -- Polarization resistance method -- Stern Geary equation -- Tafel slope; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.121003
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Polarization resistance method (PRM) is applied to microcell and macrocell corrosion (MMC). Stern-Geary equation is modified to account for the effects of macrocell current. Dispersion of the imposed polarization current affects the corrosion rate measured by PRM for MMC. Macrocell current is correlated with the measured corrosion rate of passive rebars during MMC. Abstract: The applicability of the polarization resistance method to microcell and macrocell corrosion (MMC) has been often ignored. To address this research gap, this study investigates corrosion rate measurement by using the polarization resistance method on MMC of reinforced concrete. A modified Stern-Geary equation for MMC is proposed to consider the effects of the macrocell current. The Tafel kinetic parameters and polarization resistance are obtained by conducting potentiodynamic polarization tests in a simulated concrete pore solution. The proposed equation is validated for both active and passive steel rebars. A significant overestimation is found for passive steel rebars while a substantial measurement error is found for active steel rebars due to the macrocell current.