Acoustic Emission Characterization of Corrosion Induced Damage in Reinforced Concrete

The deterioration of steel reinforced concrete caused by reinforcing bar corrosion is recognized as a major technical problem in the State of Florida and nationwide. This mode of failure is usually recognized in the final stages when surface cracking and spalling of the concrete occurs. The purpose of this study is to extend work previously reported on a nondestructive monitoring technique to detect, characterize, and locate corrosion induced structural damage. Acoustic emission technology is used to monitor and characterize the deterioration process in a series of controlled laboratory tests. By comparing measured acoustic emission characteristics, including counts and amplitude distributions, with physical examination of test specimens at various phases of corrosion induced damage, a relation between the observed damage and the attendant acoustic emission is developed. The study illustrates the sensitivity of the method to the ongoing deterioration process and explores its use as a corrosion damage monitoring technique. Various aspects of the experimental results are discussed.