Modélisation de l’endommagement et de la fissuration dynamique par une approche à champs de phase, implémenté dans un cadre de résolution temporelle explicite

Dynamic fracture a complex phenomenon that remains challenging to predict, posing significant difficulties for industrial applications. Since the early 21st century, numerical approaches have become widely adopted to investigate transient fracture mechanisms. Among these, damage gradient models have gained increasing attention for modeling brittle fracture in both quasi-static and transient regimes. However, these models are predominantly restricted to academic research due to several limitations, one of the most significant being the high computational cost due to both fine mesh requirements and expensive resolution strategies. These present studies propose an alternative resolution strategy in which the model equations are integrated using an explicit time integration scheme. This approach needs the use of timedependent damage formulations, which may be either first- or second-order leading to parabolic or hyperbolic partial differential equation, respectively.Extending the damage formulation to rate dependent model or damage inertia also raises fundamental physical questions about their necessity. The findings of this study demonstrate the influence of incorporating damage viscosity and inertia on both the crack path and crack tip speed, compared to the behaviour predicted by a standard elliptic damage PDE. While these extensions yield promising resultats in capturing dynamic damage evolution, the issue of damage thickening remains a challenge to address.