Modelling the Cyclic Response and Development of the Backbone Curve of Corroded RC Bridge Piers

Abstract

Modelling the cyclic response for the evaluation of the seismic capacity of existing corroded RC bridges is important as it is well recognised in literature. Procedures exist in the literature for the inclusion of corrosion effects through variation in different parameters like cross-sectional area of reinforcement, stress–strain behaviour, yield strength, ultimate strength and elastic modulus. In the present study, change in the inelastic buckling behaviour of reinforcement and variation in the core concrete damage characteristic under different levels of corrosion are also modelled in detail with OpenSees computational software. Modelling procedures for pristine and corroded bridge piers are validated by comparison of the cyclic response results and backbone curves obtained from analytical modelling with the experimental results reported in the literature. In this paper, the procedure for the cyclic response evaluation of piers for different mass loss percentages for corrosion has been demonstrated. From cyclic response results, the backbone curves for corroded bridge pier specimens are developed for different mass loss percentages of corrosion. The modelling strategy proposed in this paper for the cyclic response evaluation of bridge piers can be adopted for quantifying the effect of corrosion on the cyclic response of similar important structures.