An Enhanced Cell Model with Nonlinear Elasticity

Abstract

Nonlinear elasticity effects are added to an existing homogenization technique for unidirectional fiber reinforced composites. This extension of the homogenization technique increases the accuracy of numerical simulations for high strain-rate loadings. It is particularly important for any dynamic loading in which shock waves might be produced, including crash safety, armor, and munitions applications. Examples illustrate that elastic nonlinearity can make substantial contributions at strains of only a few percent. These contributions are greatest during post-yield inelastic deformation. The micromechanics-based homogenization technique is shown to facilitate use of an efficient approximate treatment of elastic nonlinearity in composites with isotropic matrix materials.