A NonSmooth Contact Dynamics-based multi-domain solver

Abstract

Cet article présente d'une part une stratégie de modélisation dédiée à la simulation micromécanique des interactions entre corps, et d'autre part, sa mise en oeuvre numérique. Cette stratégie repose sur une formulation de type décomposition de domaines d'une méthode multicorps périodique dans le cadre de l'approche Non Smooth Contact Dynamics de Moreau (Moreau, 1988). Les potentialités de cette méthode sont illustrées par la complexité des interactions possibles: interactions entre éléments d'une discrétisation, entre corps discrétisés ou rigides, en compression (contact) lente ou sous impact, en glissement (frottement) ou en traction (fissuration-rupture), etc. La plateforme numérique associée, Xper, repose sur une architecture orientée objet composée de bibliothèques indépendantes spécifiquement développées pour: (1) la résolution des équations aux dérivées partielles, (2) la gestion des interactions surfaciques complexes et l'intégration en temps associée, (3) la modélisation des comportements volumiques. La pertinence numérique de l'approche est illustrée sur des exemples de fissuration de matériaux hétérogènes. ABSTRACT. This paper presents a micromechanical modeling strategy for complex multibody interactions and the associated numerical framework. The strategy rests on a periodic multibody method in the framework of the Non Smooth Contact Dynamics approach of Moreau (Moreau, 1988) extended to classical domain decomposition problems. Many complex interactions can be taken into account : interactions between discrete elements, between discrete or rigid bodies, (quasistatic) contact or impact, friction or adhesion, decohesion (cracking), etc. The associated numerical platform, Xper, is composed of three independant libraries with Object Oriented Programming. The libraries are specifically developed for : (1) the solution of systems of partial differential equations (PDEs), (2) the modeling of complex interaction problems and the time discretization, (3) the integration of complex non linear constitutive models. The ability of this computational approach is illustrated by two examples of fracture of heterogeneous materials.

Contact Dynamics modeling of viscoelastic granular materials using irregular polyhedral particles

“…The numerical simulations were performed using the LMGC90 software, which handles the interaction of rigid polyhedral particles [9,[13][14][15][16][17] . This software is based on the Contact Dynamics (CD), which is a discrete element approach for the simulation of non-smooth granular dynamics [18][19][20].…”

Cohesive GTN model for ductile fracture simulation

“…The numerical simulations are performed using the XPER software dedicated to the simulation of frac ture dynamics of heterogeneous materials [47,48]. This computer code proposes a periodic homogenization framework under small or finite strain theories, but it can also be used for more general structure computa tions.…”

“…The loading consists in imposing the vertical component along the y axis of the velocity to Uy for the upper part of the specimen and to -U7y for the lower part of the specimen. The calculation are made using an explicit finite element solver with an implicit contact resolution, see [48] for details. Since softening behaviors induce instabilities, a dynamical formulation is here employed, again see [48].…”

“…The calculation are made using an explicit finite element solver with an implicit contact resolution, see [48] for details. Since softening behaviors induce instabilities, a dynamical formulation is here employed, again see [48]. This formulation however requires very small time steps (ôt about 10-9 s to 10-8 s).…”

Large-Displacement Response of Unreinforced Masonry Structures: Comparison Between Analytical Solutions and Dem Models Including Open-Source Software

“…In this paper, we investigate the open source software LMGC90 [12] as a tool for modeling masonry structures subjected to earthquakes. This software was originally developed for spherical elements, simulating rapid granular flows [14].…”