Multifield Description of Microcracked Continua: A Local Model

Abstract

In the present paper, a continuum model used to describe brittle microcracked bodies is proposed. The configuration of the body is represented by two fields: the displacement field and an appropriate approximation of the microcrack density. The evolution of the latter field is regulated by the balance of the actions of the microcracks on each other. Moreover, the introduction of a damage entropy flux in the Clausius-Duhem inequality allows one to obtain appropriate criteria of damage growth directly from balance equations. The mathematical structure of the model thus obtained is different from those based on internal variable schemes and allows one to overcome some of their theoretical shortcomings. A simple example, although limited to an elastostatic case, allows one to recognize the basic difference between the model presented here and the models with internal variables, and to underline the potentialities of the proposed approach.