An outdoor research study was conducted using calcium nitirite as an admixture in salty concrete to inhibit the corrosion of black steel reinforcing rebars in marine and deicing salt environments. Thelong term results from the use of this admixture to inhibit corrosion in such bars in chloride-contaminated concrete is reported in this article. In a coparison series of test slabs, epoxy-coated rebarswere used as another alternative corrosion protection system. During testing of 18 reinforced concrete slabs over 7 years, nondestructive tests were made for corrosion current, half-cell potential, driving, voltage, and resistivity as well as visual survey. It was found that the nondestructive corrosion measurement techniques and the collected data correlate well with the visual survey of the concrete slabs under test. Also, the magnitude of corrosion current flow between the mats in salt-contaminated concrete and salt-free concrete, measured periodically, can be used semiquantitatively to monitor the performance of corrosion protection materials. These and other study findings are discussed.
Abstract