Evaluation of 1-benzyl-4-phenyl-1h-1,2,3-triazole as a Corrosion Inhibitor in Reinforced Concrete Elements

Reinforced concrete plays a wide role in many civil structures such as highway bridges, residential buildings, and critical infrastructure such as nuclear facility safety related structures. Carbon steel is typically chosen as reinforcement to provide further durability to concrete in the form of reinforcement bars, or rebars, embedded in the concrete. This rebar is susceptible to the effects of corrosion, which can lead to delamination of the concrete cover and loss of component strength or possible failure if not prevented and/or mitigated. One method of mitigating corrosion in reinforced concrete is through the use of corrosion inhibitors. This research evaluates the usage of a green synthesized organic compound known as 1-Benzyl-4-Phenyl-1H-1,2,3-Triazole (BPT) to be used as a corrosion inhibitor for carbon steel rebars in reinforced concrete. Methods of evaluation include electrochemical tests in synthetic pore solutions (SPS, 8.33g/L NaOH + 23.3g/L KOH + 2.0g/L Ca(OH)2; pH: 13.6), following a modified ASTM G180 procedure as well as electrochemical impedance spectroscopy and anodic cyclical potentiodynamic polarization. These measurements indicated BPT inhibited the corrosion rate of steel in SPS in presence of 2M NaCl at concentrations higher than 2 mmol/L, and had an optimal concentration of 3 mmol/L. Further evaluation included physical-mechanical and electrochemical tests in mortar specimen, finding a concentration of 2.5 mmol/L BPT to be most ideal. Compression, resistivity, and porosity tests after 28 days showed improvement when mortar specimen included BPT, though more time is needed for electrochemical tests after accelerated exposure following a modified ISO11474 to determine effectiveness.