Conclusion

Fracture mechanics as applied to laminated composite materials is not a natural derivative of the classical tools and concepts developed since the 1920s for homogeneous isotropic metallic materials. Indeed, its application to laminated composite structures is a complex and relatively recent field, which calls for the necessary caution due to their highly anisotropic and heterogeneous nature. Composite structures are complex materials, already displaying structural characteristics on the scale of the elementary fold. In particular, the tenacities associated with different modes of composite failure (e.g. delamination) depend on a large number of parameters such as geometry, type and orientation of upper and lower plies, loading rate or the presence of out-of-plane compressive stress. A physical understanding of fracture mechanisms is a prerequisite for numerical modeling of this type of...