Static notch sensitivity in orthotropic materials and composites

A theoretical study on defect and notch sensitivity in orthotropic materials is carried out, with the aim to make explicit the bridging between notch effect and defect sensitivity. Analogies and differences with the isotropic case are highlighted, and the relevant parameters necessary to quantify the transition from a fracture-mechanics-controlled to a notch-mechanics-controlled behaviour are discussed in details. The validity of the proposed approach is proven taking advantage of a bulk of experimental data taken from the literature and related to thermoplastic and thermosetting composite laminates with different stacking sequences and notch geometries.