Evaluation of Microencapsulated Corrosion Inhibitors in Reinforced Concrete
Reinforced concrete (RC) structures are vital to the US infrastructure due to their relatively low cost, durability, and high strength. However, when concrete cracks, the steel reinforcement is susceptible to corrosion due to the ingress of harmful agents. The resulting corrosion products occupy a greater volume than the steel reinforcement, leading to an expansion that creates tensile stresses within the concrete matrix, causing further deterioration through cracking, delamination, and spalling. In order to mitigate corrosion, this study aims to develop and characterize the performance of encapsulated calcium nitrate tetrahydrate embedded in reinforced concrete beams for corrosion inhibition at varying concentrations (as a percentage by weight of cement). The corrosion and inhibitor penetration mechanism between microcapsules/concrete and rebar/concrete interfaces was preliminarily characterized using an electrochemical impedance spectroscopy (EIS) technique. In addition, the effects of the microcapsules on the concrete properties, such as the compressive strength and surface resistivity, were evaluated.