Acoustic Emission Monitoring of RC Beams Corroded to Different Levels Under Flexural Loading

Abstract

The focus of the research is to evaluate the behavior and performance of large-sized reinforced concrete (RC) beams corroded to different levels using local acoustic emission (AE) technique under flexural loading. With increase in the level of corrosion, the ultimate load-carrying capacity and midspan deflections are drastically reduced, which is indicative of increasing brittleness and decreasing ductility in the corroded beams. AE monitoring of corroded RC beams under flexural loading clearly demonstrated various failure progression stages right from initiation of cracking to their ultimate failure. As the level of corrosion increases, a significant drop in cumulative AE hits is observed. AE activity depicted as AE phases is delayed and diminished due to the attenuation of the captured AE signals caused by cracks developed due to corrosion. AE event plots give a pictorial representation of actual development and progression of micro- and macrocracking inside concrete as the corroded beams are subjected to flexural loading. The assessment of damage in RC beams subjected to simultaneous corrosion and loading would facilitate in situ nondestructive evaluation of actual RC structures in the future.