Integral-type regularization of non associated softening plasticity for quasi brittle materials

Abstract Within the framework of infinitesimal elasto-plasticity for describing concrete behaviour, this paper proposes a new non-local constitutive model. Particularly, a non-local integral-type regularization technique is applied to the three-invariant Menetrey-Willam model, here modified by the inclusion of a non-associated flow rule. The resulting model allows for taking into account the role of the intermediate principal stress and the Lode parameter, as well as to control inelastic dilatancy. A regularization scheme is hence introduced to circumvent strain localization and resolve the incapability of objectively describing localized material failure. One- and three-dimensional Finite Element analyses are developed to prove the soundness of the novel implemented regularized scheme and the upgraded response with respect to a local approach.