A NEW FAILURE CRITERION FOR NONLINEAR COMPOSITE-MATERIALS

A new failure criterion based on the total strain energy density appro ach is introduced for an equivalent linear elastic material. The total strain energy is composed of the clastic strain energy and the plasti c strain energy. The proposed criterion can be used to predict failure of fibrous composite materials subject to uniaxial, biaxial, or multi axial stress state. The proposed criterion takes into account the diff erent behavior of bimodular composites in tension and compression. Giv en the stress-strain diagrams in the principal material directions. th e failure of the material at any fiber orientation angle under an impo sed stress state can be predicted. The results are compared with the c orresponding available experimental data. In addition, the predicted f ailure stresses are compared with these obtained using available failu re criteria.