Fracture assessment of sharp V-notched components under Mode II loading: a comparison among some recent criteria

Different criteria are available in the literature to assess the fracture behaviour of sharp V-notches. A typical and well-known criterion is based on the application of the Notch Stress Intensity Factors (NSIFs), which are able quantify the intensity of the stress field ahead of the notch vertex. This work considers two recent energy-based criteria applied here to sharp V-notches. The first criterion is based on the averaged value of the strain energy density (SED) while the second one, called Finite Fracture Mechanics (FFM) criterion, is available under two different formulations: that one by Leguillon et al. and that one by Carpinteri et al. Considering the averaged SED criterion, a new expression for estimating the control radius Rc under pure Mode II loading is proposed and compared with the sound expression valid under pure Mode I loading. With reference to pure Mode II loading, the critical NSIF at failure can be expressed as a function of the V-notch opening angle. By adopting the criteria considered here, the expressions for the critical NSIF are presented and analitycally compared. After all, the considered criteria are employed considering sharp V-notched specimens under in-plane shear loading in order to investigate the predictive capability of each approach in the fracture assessment. With this aim, a large bulk of experimental data taken from recent and past literature are used for the comparison.