Influence of time-dependent corrosion on strength and ductility of reinforcing steel bars exposed to natural and aggressive environments

Abstract

The reinforcement corrosion in is a major and most frequent reason of degradation for reinforced-concrete (RC) structures throughout the world, leading to their premature deterioration before design life was attained. Corrosion weakens the mechanical properties of rebar by ingress of aggressive ions due to various environments. In this study, a total of 99 specimens with six different diameters were tested, for three exposure periods, and six different environments, to assess the influence of corrosion on mechanical properties of reinforcing bars. Degradation relationships of strength and ductility with exposure period and rebar diameter, were analyzed, and three equations were proposed to formulate the relations. It was found that, the ultimate strength of 8.6% of the corroded bars falls below the original yield strength; after 5 years of exposure in natural atmosphere, reduction in mechanical properties was insignificant; a detergent solution environment could cause the strength loss of 24.8%.