Do Notched Thick Plates Have Strength in Shear

This paper summarizes recent theoretical studies on the three-dimensional singular stress state at sharp notches in infinite (or large) plates of finite thickness subjected to in-plane loading. In general, such loading produces a number of singular states: in-plane singularities (normally described as KI and KII fracture modes and known as Williams’ solution), singular states associated with corners and the out-of-plane singularity (KO mode), which is generated due to the Poisson’s effect. The latter mode has an interesting behavior and its intensity increases as a power function with the increase of the plate thickness when the notch is stresses in shear mode. From finite fracture mechanics considerations it is clear that at some certain thickness the out-of-plane singular mode will dominate over the fracture zone and with the further increase of the plate thickness will affect the strength of the notched plate, virtually reducing it to zero.