A fracture energy based constitutive model for the analysis of reinforced concrete structures under cyclic loading

This paper proposes a constitutive model for predicting the response of reinforced concrete. Of specific interest is the realistic modeling of the hysteretic behavior of concrete under quasi-statically reversed cyclic loading. The significant cyclic features of concrete are described in the model using irrecoverable strains, crack closing and reopening, nonlinear unloading curves that represent the energy dissipation, and reloading curves with the degraded reloading stiffness that account for the damage. Partial unloading/reloading is also accounted for. The model is implemented in the context of the fracture energy based smeared rotating crack approach, and validated using measured data from experiments at both the material and structure levels. Case studies show that the model is more applicable and accurate in the nonlinear analysis of reinforced concrete structures than models with idealized hysteretic schemes.