Confined concrete model under cyclic load

A uniaxial cyclic model for confined and unconfined concrete is developed. Starting from an existing model, the cyclic rules to define inelastic strain and degradation of strength and stiffness are first reviewed and then modified to produce a new concrete model with enhanced performance. Comparisons at the stress-strain level between the new and existing concrete models reveal the adequacy of the new model in terms of numerical stability and increasing degradation of strength and stiffness under increasing cyclic strain. The proposed model is validated by comparing analytical predictions with experimental results of reinforced concrete members under cyclic and dynamic loading. Good agreement is observed between analysis and experiments, confirming the ability of the model to predict the cyclic and dynamic behaviour of reinforced concrete members with mixed axial-flexural response characteristics.