Paper number 735

MESO-MACRO MECHENICAL BEHAVIOUR OF DRY FIBER FABRICS

Karine Buet Gautier¹,² Alain Gasser¹,² Jean Launay¹,² and Philippe Boisse¹,²

1Laboratoire de Modélisation et Mécanique des Structures; URA C.N.R.S 1776
ENSAM Paris/Université Paris 6, 151 Boulevard de l'Hôpital, 75013 Paris, France
2Ecole Supérieure de l'Energie et des Matériaux, Rue de Vinci, 45072 Orléans Cedex, France

Summary

Fibre fabrics are among the most efficient reinforcements for thin composites, and are increasingly used, especially in the field of transportation. They allow to achieve complex shapes in a single operation by forming a fabric on a given surface. The knowledge and modelling of dry fabric behaviour is necessary for these manufacturing. Firstly, a biaxial tensile device will be presented. To show essential proprieties of fabric behaviour, strain ratio and angular orientation between the two direction of weaving are adjustable. Tests, carried out on several fabrics, show that mechanical behaviour of fabrics is a multiscale problem, non linear and biaxial. Models, describing an elementary mesh, are then identified. It is shown that local phenomena (such as undulation variation and yarn flattening) mainly influence global behaviour. 3D simulations of the elementary mesh are performed to analyse them. The whole results are used to build specific finite elements made of woven cells.

Keywords

dry fiber fabrics, meso-macro properties, biaxial tensile test, modelling of fabric behaviour, 3D Simulations, forming simulation.