A SIMPLE ANISOTROPIC FIBER REINFORCED HYPERELASTIC CONSTITUTIVE MODEL FOR WOVEN COMPOSITE FABRICS

Based on fiber reinforced continuum mechanics theory, a simple hyperelastic constitutive model is developed to characterize the anisotropic nonlinear material behaviour of woven composite fabrics under large deformation during forming. The strain energy function for the hyperelastic model is additively decomposed into two parts nominally representing the tensile energy from weft and warp yarn fiber stretches and shearing energy from fiber-fiber interaction between weft and warp yarns, respectively. The proposed material characterization approach is demonstrated on a balanced plain weave composite fabric. The equivalent material parameters in the hyperelastic constitutive model are obtained by matching experimental load-displacement data of uni-axial tensile and picture frame tests on the woven composite fabric. The development of this anisotropic fiber reinforced hyperelastic model is critical to the numerical simulation and optimization of woven composites forming.