Corrosion Characteristics of Steel Bars Embedded in Recycled Concrete Beams under Static Loads

Abstract

To investigate the corrosion characteristics of steel bars embedded in recycled concrete beams under static loads, 12 recycled concrete beams were designed for electrochemical corrosion test taking into consideration a combination of 3 types of recycled coarse aggregate (RCA) replacement ratios (i.e., 0%, 50%, and 100%) and 4 levels of static load (i.e., 0, 0.2, 0.4, and 0.6). The results indicate that the mass losses of longitudinal tensile reinforcement and stirrup increase with both the RCA replacement ratio and the applied static load level. For corroded beams with a 50% RCA replacement ratio, the effect of an increase of 0.2 in the applied static load level on the corrosion of longitudinal tensile steel bars is greater than that of an increase of 50% in the RCA replacement ratio. For corroded beams with the same RCA replacement ratio, the maximum mass losses of longitudinal tensile reinforcement and short limbs of stirrups in the tension zone of the beams have a linear relationship with their average mass losses, and there is a positive correlation in the corrosion degree between the short limbs of stirrups in the tension zone of the beams and the longitudinal tensile steel bar. There exists a linear relationship between the pitting factor of longitudinal tensile reinforcement and its average mass loss, and the pitting factor decreases with the increase in average mass loss, which indicates that the corrosion of longitudinal tensile reinforcement tends to be uniform along the length with its increasing average mass loss.