Anisotropic damage model for woven fabric composites during tension–tension fatigue

Inelastic deformations of woven fabric composites are attributed to the formation of multitude of cracks that develop in the material in the fatigue environment. Cracks destroy material bonds and render composites more compliant. This paper presents an anisotropic damage model for glass–epoxy fabric composites accounting for the strong directionality nature of damage during a tension–tension fatigue loading. Damage is reflected through the fourth-order compliance tensor involving a damage parameter whose evolution is determined from the second invariant of the stress tensor. The model is capable of capturing permanent deformation due to damage and is checked against experimental results.