On the Presence of the Out–of–Plane Singular Mode Induced by Plane Loading With K_II = K_I = 0

摘要

Previous studies by a number of researchers demonstrated that in the case of a plane crack subjected to shear loading conditions characterized by a remote stress intensity factor, K_II, a three-dimensional singular mode (called mode O or out-of-plane mode) develops at the crack tip. This singular mode occurs due to the primary shear loading and Poisson’s effect. Similar to mode III, the O-mode is associated with the transverse shear stress components. Recent theoretical and numerical studies have also demonstrated a strong presence of this singular mode in plates weakened by pointed V-notches. Therefore, it was suggested that O-mode can play an important role in fracture initiation, particularly at large opening angles (above 102.6°) when the applied mode II is non-singular.