Get access

An approach to the modeling of viscoelastic damage. Application to the long-term creep of gypsum rock materials


Correspondence to: B. Nedjar, Université Paris-Est, Laboratoire Navier (ENPC/IFSTTAR/CNRS), Ecole des Ponts ParisTech, 6 et 8 avenue Blaise Pascal, 77455 Marne-la-Vallée, France.



A three-dimensional phenomenological model is developed to describe the long-term creep of gypsum rock materials. The approach is based on the framework of continuum damage mechanics where coupling with viscoelasticity is adopted. Specifically, a local damage model based on the concept of yield surface is proposed and deeply investigated. Among the many possibilities, we choose in this work its coupling with a generalized Kelvin–Voigt rheological model to formulate the whole behavior. Long-term as well as short-term relaxation processes can be integrated in the model by means of as many as necessary viscoelastic processes. The numerical discretization is described for an easy integration within a finite element procedure. Finally, a set of numerical simulations is given to show the possibilities of the presented model. It shows good agreement with some experimental results found in the literature. Copyright © 2012 John Wiley & Sons, Ltd.