0000000000346495
AUTHOR
Lucien Laiarinandrasana
Analyse multiéchelle d'un composite textile = Multiscale analysis of a textile composite
National audience; On propose dans cette étude de comprendre le comportement mécanique d'un composite textile. Pour ce faire, l'étude se scinde en deux parties distinctes. Dans cet article, nous présentons la modélisation multiéchelle qui fait suite à une étude expérimentale. Son objectif est double : comprendre la nature du comportement macroscopique observé et expliquer l'origine des endommagements susceptibles d'apparaître. L'étude expérimentale du matériau fait l'objet d'un premier article.
Durability of a 3D woven composite assisted by finite element multi-scale modelling
International audience; The textile composite studied is a 3D woven composite. A unit cell is defined by using microscopic examinations of the microstructure. A multiscale approach assisted by the finite element method is performed in order to estimate the effective properties of the composite and then to access to local stress field. This approach allows the determination of the kind of load to which warp yarns are subjected. Moreover, detailed analysis of damaged model using different configurations of broken yarns are treated. The evolution of the stress concentration coefficient highlight the load transfers due to consecutive yarn breaks.
Modelling the effect of porosity on the mechanical properties of unidirectional composites. The case of thick-walled pressure vessels
International audience; The present article highlights morphological features present in composite pressure vessels. The use of X-ray microtomography provides three-dimensional information about the voids in a large thick-walled type 3 pressure vessel at the mesoscopic scale. The observations show that the porosity structure depends strongly on composite thickness and orientation. A numerical approach is proposed to model realistically the damage phenomena in pressure vessels.
Analyse multiéchelle d'un composite textile
National audience; On propose dans cette étude d'expliquer le comportement mécanique d'un composite textile au travers d'un processus multiéchelle. Les propriétés mécaniques nécessaires à la réalisation des calculs ont été déterminées par une étude expérimentale préalable.
Bending effect on the risk for delamination at the reinforcement/matrix interface of 3D woven fabric composite using a shell-like RVE
This paper presents a computational homogenisation-based technique for flexural effects in textile reinforced composite planar shells. An homogenisation procedure is used for the in-plane and the out-of-plane behaviour of three-dimensional woven composite shells, taking the in-plane periodicity of the material into account while relaxing any periodicity tying in the thickness direction. Several types of damage (matrix or reinforcement cracking, delamination, …) can appear in a composite material. In this paper, material non-linear computations are used to assess the importance of bending on the risk for delamination at the reinforcement/matrix interface. The normal and tangential stresses a…