Nonlinear Behavior of Woven Fabric Composites

Abstract

This paper examines the non-linear elastic behavior of fabric composites. Three types of non linearity including the shear deformation of fill threads, the extensional deformation of the pure matrix regions and transverse cracking of the warp regions have been taken into considerations. The non-linear constitutive relation developed by Hahn and Tsai is adopted in this analysis and the fiber undulation and bridging models developed by Ishikawa and Chou are also applied. Results of the analysis for a glass 8 harness satin/polyimide composite compares remarkably well with the experimental stress-strain curve. The analyses also show that the nonlinear effects are less pronounced for fabrics assuming larger geometrical repeating length due to the increasing in fluence of the "bridging effect." As a result, both knee stress and strain increase with the geometrical repeating length.