A viscoplasticity model to predict delayed behavior of materials: parametric study and application to ancient textiles
Résumé
Numerical modeling offers a great tool for evaluating textile materials and predicting their behavior. Many researchers have modeled the behavior of textiles. However, none of these proposed models that take into account the effect of time, namely the creep behavior. This phenomenon is of great importance when dealing with historical and museographical textile such like tapestries since they are hung for a long period of time. And under their own weight will undergo permanent deformations, later in time. In this work, we propose a new frame of work that includes a time-dependent visco-elastic network responsible of the time-delayed response, and an elastic-plastic network that is able to simulate permanent deformations especially in the weak zones of the material. This mechanical coupling is ensured by the use of the rheological model implemented in Abaqus, the two-layers viscoplasticity. It’s a well-known model and widely used nowadays to model structures that undergo cyclic behaviors and relaxation after forming process. In this work, we first explore this model by mean of a 1D numerical integration, which allows a direct parametric study and to highlight its ability to simulate creep: primary, secondary and tertiary. Then this model implemented in Abaqus, was used to study the creep of hanged tapestries. This needed an analytical formulation of the problem in the tensorial form, the tapestry was simulated as a shell. It allows to find the evolution of the tapestry with time and to predict the failure zones in tapestries.
Origine | Fichiers produits par l'(les) auteur(s) |
---|