Implementation and validation of a three-dimensional plasticity-based deformation model for orthotropic composites

A new orthotropic elasto-plastic constitutive model has been developed to predict the inelastic response of composite materials under high velocity impact conditions. The model is driven by experimental stress-strain curve data stored as tabular input allowing for a very general material description. The theoretical details of the elasto-plastic deformation part of the material model are briefly summarized. This summary is then followed by details of the numerical implementation of the model as MAT213 (suitable for use with solid elements) into the commercial transient dynamic finite element code, LS-DYNA. The theoretical basis and the numerical implementation of the constitutive model are validated by using two sets of validation tests involving a widely used unidirectional composite, T800/F3900 - composite laminates used in coupon level tests and a low velocity impact test on a flat panel. Results show that the implementation is efficient, robust and accurate.