Stirrup effects on the bond properties of corroded reinforced concrete

Abstract

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