Bond-Slip Model of Corroded Reinforced Concrete and Its Application in Members

The corrosion of longitudinal rebar and stirrups will cause serious degradation to the bond performance between steel bars and concrete. To investigate the impact of both longitudinal rebar and stirrup corrosion on the bond behavior, 35 reinforced concrete (RC) pull-out specimens were subjected to accelerated corrosion tests of electroosmosis-constant current-dry wet cycles and pull-out tests, and then the influence laws of the degree of corrosion of the longitudinal reinforcement, degree of corrosion of the stirrups, cover thickness, stirrup spacing and longitudinal reinforcement diameter on the bond performance were studied. The bond behavior between corroded steel bars and concrete was analyzed from the aspects of corrosion form, failure mode and bond strength. Subsequently, based on the experimental data, a modified bond-slip constitutive model that considers the design parameters, stirrup corrosion and longitudinal rebar corrosion was built and verified. Finally, based on the established modified bond-slip constitutive model, the corroded RC column was simulated, and the accuracy of the established modified bond-slip constitutive model was verified at the component level.