An analytical model for evaluating lateral load-displacement curve of corroded reinforced concrete beams under cyclic loading

Abstract

This paper presents an analytical model for evaluating the nonlinear response of corrosion-affected reinforced concrete (RC) beams under cyclic loading conditions. The analytical model addresses the interdependent flex- ural and shear mechanisms through two key components: (i) a flexural analysis module employing moment- curvature relationships that integrate corrosion-induced material deterioration in the concrete cover, tension in longitudinal reinforcement, buckling effects of compressive longitudinal reinforcement, along with plastic hinge length reduction; and (ii) a modified shear capacity model based on Sezen and Moehle’s model but incor- porating ductility-related strength reduction and corrosion damage parameters for both concrete and transverse reinforcement. The model was validated against experimental data from cyclic loading tests on eleven cor- roded RC beams. The results indicate that the model can accurately predict the load-displacement curve and failure mode to a reasonable extent. A strong correlation with the experimental peak load was observed, with an average ratio of 1.03 and a coefficient of variation (COV) of 0.08. However, the predictions for ultimate displacement show more variability, with an average ratio of 0.94 and a COV of 0.32.