Constitutive model for 3D cyclic analysis of concrete structures

A three-dimensional (3D) concrete material model for nonlinear finite-element analysis of concrete solids under short-term cyclic loading is presented, The proposed model is a hypoplastic orthotropic model based on a stress-equivalent uniaxial strain relation that is generalized to take into account triaxial stress conditions. The directions of orthotropy are assumed to coincide with the current principal stress directions according to the rotating smeared-crack approach. The model includes the effect of triaxial nonlinear stress-strain behavior, tensile cracking, compression crushing, and strain softening. The proposed model is compared in detail with selected test data of concrete behavior under 3D cyclic stress loading. These correlation studies demonstrate the ability of the model to represent the observed experimental behavior.