Three-dimensional finite element analysis of crack-tip fields of clamped single-edge tension specimens – Part I: Crack-tip stress fields

A systematic study has been carried out based on three-dimensional finite element analyses to investigate the impact of the in-plane and out-of-plane dimensions on the crack-tip stress fields of clamped SE(T) specimens. Both plane-sided and side-grooved specimens with a wide range of thickness-to-width ratios (B/W = 1/2, 1, 2 and 4), crack lengths (a/W = 0.3, 0.4, 0.5, 0.6 and 0.7) and strain hardening exponents (n = 5, 10 and 20) are included in this study. The through-thickness distributions of J and CTOD as well as the distribution of the opening stress (σθθ) ahead of the crack tip at different crack front locations are presented. The distributions of J and CTOD over the crack front and those of σθθ ahead of the crack tip are impacted by a/W, B/W, n and the type of specimens (i.e. plane-sided or side-grooved). In addition, the empirical equation for calculating CTOD from J for SE(T) specimens developed by Shen and Tyson based on two-dimensional plane-strain finite element analyses is found inadequate to be applied to three-dimensional SE(T) specimens except for the plane-sided specimens with n = 10 and side-grooved specimens with n = 5.