Corrosion rate measurement by using polarization resistance method for microcell and macrocell corrosion: Theoretical analysis and experimental work with simulated concrete pore solution

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. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

This study investigates corrosion rate measurement of microcell and macrocell corrosion (MMC) in reinforced concrete using the polarization resistance method. A modified Stern-Geary equation for MMC is proposed to account for the effects of macrocell current, and it is validated for both active and passive steel rebars. It is found that there is a significant overestimation for passive steel rebars, while a substantial measurement error exists for active steel rebars due to the macrocell current.