Evaluation of three unit cell models in predicting the mechanical behaviour of 3D four-directional braided composites

This paper compares three types of the unit cell models in their capability to predict the mechanical behaviour involving macroscopic material properties and mesoscopic stress distribution for the 3D four-directional braided composites. The unit cell model is periodically meshed in Hypermesh 11.0 and finite element analysis is performed under six kinds of monotonic loading cases by employing ABAQUS/Standard 13.0. Then the effective material properties of the braided composites are obtained in the framework of mean field homogenization. The influences of the yarn cross-section shape and curvature on the macroscopic material property and mesoscopic stress distribution are discussed. This paper lays the ground for choosing the yarn cross-section shape and trajectory in the established unit cell model for the 3D four-directional braided composites.