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Many chemical additives designed to inhibit the corrosive effect of salt on rebars are being marketed. Their effort on Portland Cement Concrete is neither known or understood. This study is an attempt to determine if there is an effect and to understand the nature and results of the effects

This research builds on a previous investigation, which found that corrosion-inhibitor-added deicing salts caused degradation of concrete by both anions and cations. The latest research phase looked at methods to detect the chemical reactions between concrete and corrosion-inhibitor-added deicing salts, and to determine the chemical compositions of the precipitates formed by chemical reactions between concrete and the corrosion-inhibitor-added deicing salts. The research led to the following conclusions: * a simple method was developed for the detection of chemical reactions between deicing chemicals and concrete; * the results provided clear evidence of the chemical reactions between concrete and the corrosion-inhibitor added deicing salts; * the different amounts of precipitates (chemical reaction products) found in the test cells were dependent on the type and concentration of corrosion-inhibitor-added deicing salts; * precipitates formed by chemical reactions between deicing chemicals and concrete were identified by using chemical analysis, scanning electron microscopy, and X-ray diffraction analysis; * and precipitates were calcium and/or magnesium phosphates as a major component, and gypsum as a minor component.