Non-Destructive Evaluation of Corroded and Corrosion Repaired RC Beams

Abstract

Reinforced concrete structures have suffered the deterioration due to corrosion despite the protection that concrete provides to embedded steel. Since steel corrosion remains unnoticed inside the concrete, it further accelerates and can cause loss of life and property. This report discusses the effects of deterioration caused to reinforced beams due to corrosion at different levels. six RC beams (127 x 227 x 4100 ) mm were cast one was kept as control beam and rest five of which were corroded to different levels i.e. (20days, 30days, 40days, 50days and 60days) by impressed current technique, while one remain as control beam . All five beams were subjected to vibration based health monitoring at the end of their respective corrosion period. This was done to investigate the effect of corrosion on dynamic properties of beams with increasing corrosion. Vibration characteristics of beams showed decrease in vibration amplitude and frequency of beam with increasing level of corrosion. After dynamic analysis ,each beam was tested under static two-point loading and corresponding loads and deflections were recorded along with Acoustic emission hit parameters were recorded which showed the behaviour of crack. The static load deflection characteristics of beams corroded to different level shows decrease in load carrying capacity, deflection capacity with the increase in age of corrosion. Most importantly it was noticed that as corrosion increased the fail