Mechanical Behavior of Corroded Protruding Rebars From Unfinished Concrete Structures

摘要

In the current study, the effects of chloride-induced corrosion on B500c semi-embedded steel bars, both immersed in a salt-spray chamber and on protruding areas of existing structures, are evaluated in terms of mass loss and mechanical characteristics. Comparison of corrosion damage rates between bare and semi-embedded specimens at the early stages of the corrosion test, indicates that the bare steel bars present quite high mass losses, which however, over exposure time reach approximately similar rates to the ones presented by the semi-embedded steel bars. As far as mechanical characteristics are concerned, the mass loss of semi-embedded steel rebars, at the protruding site, is related to the strength and ductility properties drop. At the same time, while the corrosion exposure time is increasing in bare samples, a continuous-almost linear and proportional to the mass loss-reduction of the strength properties and the uniform elongation is observed. Finally, a worth referring point is the appearance of two Ludder areas on stress-strain diagrams of semi-embedded steel bars, a point that confirms the different corrosion mechanism of protruding areas in comparison to the bare or the wholly embedded ones.