Mesomechanical Model for Numerical Study of Two-Dimensional Triaxially Braided Composite

A mesoscale three-dimensional finite-element model is set up to model two-dimensional triaxially braided composites. Unit cell scheme is used to take into account braiding architecture as well as mechanical behavior of fiber tows, matrix, and fiber tow interface. A 0 degrees/+/- 60 degrees braiding configuration has been studied. A failure criterion and progressive damage evolution model taking into account fiber tow and tow interface has been applied to theoretically predict interlaminar and intralaminar failure mode. Straight-sided specimen testing has been carried out in both axial and transverse direction. Results obtained in the tests as well as finite-element approaches are discussed. This paper also discusses the main feature of the model through an extensive parameter study. Overall, by comparison of experiment and model results, the applicability of the developed model is assessed and the failure process is investigated; furthermore, conducted parameter study enhances the strength of the model, which lies in the correlation of model parameters and identification of damage modes with experimental data on the overall stress strain curves.