Elastoplastic Constitutive Model for Concretes of Arbitrary Strength

Abstract

In this paper, the main features of a new elastoplastic constitutive formulation for concretes valid for a large spectrum of strengths, including normal to high strength concretes, are presented. The model, depending on the three stress invariants, has a non associative flow rule, a non uniform hardening law, and an isotropic softening law based on the fracture energy of modes I and II. It considers as material parameters the uniaxial compressive strength, which is a macroscopic property, as well as the performance parameter for concretes. The latter is an index defined by the authors in previous works which takes into account some properties of the concrete mixture. Moreover, the maximum aggregate size is considered in order to evaluate the concrete fracture energy. As result, a constitutive model capable to distinguish different mechanical behaviors of concretes of different qualities is obtained. Particularly, in this work a description of the constitutive model is presented, with focus on the hardening and softening laws, ending with the presentation of numerical experiments.