Evaluation of Greener Corrosion-Inhibiting Admixtures for Steel Reinforcements in Concrete

In this study, corrosion of thermo-mechanically treated (TMT) rebars with and without 3.5% NaCl for various concentrations (0.1%, 0.2%, 0.3% and 0.4%) of green corrosion inhibitors, namely glucosamine and stevioside, was systematically studied in simulated concrete pore solution (SCPS). Open-circuit potential measurements revealed that inhibited system showed passive behaviour compared with control system in SCPS. Potentiodynamic polarization studies revealed that inhibitor stevioside offers more than 88% inhibition efficiency at 0.3% concentration in SCPS containing 3.5% NaCl. Similarly, linear polarization resistance and impedance measurements showed higher polarization resistance and charge transfer resistance values, respectively, at 0.3% concentration for inhibited systems when compared with control (without inhibitor).