Effect of Assumed Tow Architecture on Predicted Moduli and Stresses in Plain Weave Composites

Abstract

This paper examines the effect of assumed tow architecture on the predicted moduli and stresses in plain weave textile composites. In particular, the effect of how a constant cross-section is assumed to sweep-out the volume of a tow is explored. Two architectures are examined which have a sinusoidal tow path and a lenticular cross-section. Three-dimensional finite elements are employed to model a T300/Epoxy plain weave composite with symmetrically stacked mats. Macroscopically homogeneous in-plane extension and shear and transverse shear loadings were considered. Symmetries are exploited which permitted modeling of only 1/32nd of the unit cell. Accounting for the variation of material properties throughout each element is determined to be necessary for accurate prediction of stresses in the composite. For low waviness, the two tow architectures examined are very similar. At high waviness, the stress predictions are much more sensitive to the assumed tow geometry.