Micromechanics models for the elastic constants and failure strengths of plain weave composites

In this paper, two models are presented for plain weave composites. One is finite element analysis (FEA) model for elastic constants, namely, sinusoidal yarn model. Another is analytical model for failure strengths, namely, sinusoidal beam model. The FEA model is generated by interfacing an in-house computer code with FEA software strand6, and the analytical model is developed using the theory of elasticity. Numerical studies are carried out using the present models to investigate the effects of some major geometrical parameters on the properties of plain weave composites. It is concluded that the failure strengths are closely related to the fiber volume fraction of a yarn, and the mechanical properties are closely related to the overall fiber volume fraction of the composites. An experimental testing program is conducted for T300/934 plain weave composites to validate the developed models. A good agreement exists between the predicted and measured results.