Residual seismic capacity of beam-column components with corroded reinforcement

Several concrete structures in tectonically active regions of the world are exposed to chloride ingress from seawater, saltwater, and other sources, making them vulnerable to corrosion-induced deterioration. Although it is well-known that corrosion-induced deterioration influences the force-displacement behaviour of corroded concrete components under cyclic loading, no adequate provisions have been incorporated into state-of-practice seismic assessment procedures to account for the influence of corrosion on the modeling parameters and acceptance criteria for concrete components. Using an extensive database of 418 material-level and 271 component-level test specimens with deformed bars, this paper presents simple formulations for evaluating the residual yield strength, ultimate strength, ultimate strain capacity, and bond strength of corroded deformed bars. Conclusions from the material-level study are then used in proposing approaches for predicting the flexural strength, shear strength and failure mode of beam-column components with corroded deformed bars. Subsequently, a simple reduction factor formulation is proposed for predicting corrosion-induced deformation capacity deterioration in corroded concrete components. The proposed reduction factor is demonstrated to be applicable to current deformation capacity formulations in ASCE/SEI 41–17 and Eurocode 8