A lumped plasticity model for corrosion damaged reinforced concrete columns

Chloride-induced corrosion is one of the most important reasons for the strength degradation of reinforced concrete (RC) bridges. As the piers of RC bridges are important element to sustain lateral loads, corrosion of columns in pier may lead to significant degradation. So it is necessary to have an appropriate evaluation technique to assess the effect of corrosion on the RC columns behaviour. Numerical modelling approaches which are based on the concentrated plastic hinge can predict structural behaviour rapidly and with acceptable accuracy which are highly regarded by engineers. In this study, a numerical approach is conducted to develop an empirical lumped plasticity model for corroded RC column elements. 13440 RC column specimens, including corroded and uncorroded, rectangular, and circular cross sections are analysed under monotonic and cyclic loading. Lumped plasticity model is extracted based on the regression of the cyclic and monotonic analysis results. Finally, calibrated model is verified through experimental and out-of-parametric study models with high accuracy. The new developed plastic hinge model can be used to model and analyse corroded bridge columns rapidly. The result can be appropriate to be employed for modelling in the further assessment such as fragility analysis or rehabilitation.