Stirrup effects on the bond properties of corroded reinforced concrete

Abstract

Several bond–slip models considering corrosion effects are available in the literature to describe the change in bond due to corrosion of longitudinal reinforcement. However, these models do not consider either the beneficial effect of stirrups or corrosion of the stirrups. This is very important because stirrups provide a confinement effect that enhances the bond strength of reinforcement, but the effect deteriorates with corrosion impacts. To address this limitation, a new bond–slip model was developed that includes the influence of corrosion of both the reinforcement and stirrups. More significantly, the model also provides a correlation between the corrosion in stirrups and longitudinal reinforcement. This means that the model can be applied with knowledge of the corrosion of either the longitudinal reinforcement or the stirrups. This is beneficial for the prediction of the corrosion level of longitudinal bars and, to take a step further, for the prediction of the mechanical behaviour of structures as it is relatively easy to measure the corrosion level of stirrups physically. The new model is presented in this paper along with a parametric study based on the developed model.