Triaxial Constitutive Model for Concrete under Cyclic Loading

Abstract

This paper presents a material model for the analysis of concrete under multiaxial, cyclic loading conditions. An elastoplastic formulation, having a nonassociative flow rule to capture compression-dominated behavior, is combined with a rotating smeared-crack model to capture the tension-dominated behavior. The proposed formulation resolves the issues that exist in many available concrete material models related to properly capturing the crack opening and closing behavior and accounting for the effect of confinement on the strength and ductility under compression-dominated stress states. The accuracy of the model is validated through analyses for reinforced concrete components. A parametric study demonstrates the importance of accounting for the increase in ductility due to the confinement effect. Additional analyses elucidate the impact of using different yield surfaces for the elastoplastic model on the simulation results.