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

This study investigates the in-plane and out-of-plane constraint parameters (namely Q, A2, h and Tz) for clamped single-edge tension (SE(T)) specimens based on a comprehensive set of three-dimensional finite element analyses reported in a companion paper (Part I). The impact of the crack length (a/W), thickness-to-width ratio (B/W) and strain hardening exponent (n) on the constraint parameters, and the interaction between the constraint parameters are examined. For specimens with a given B/W, Q, h and A2 at the mid plane in general increase as a/W increases, but Tz at the mid plane is independent of a/W. The impact of B/W on the distributions of Q, A2 and h over the crack front is dependent on a/W, but Tz decreases as B/W decreases regardless of a/W. The Q, A2 and h values are impacted by n, but Tz is essentially independent of n. For SE(T) specimens, Tz is more appropriate to capture the out-of-plane constraint. The investigation of the interaction between the constraint parameters indicates that Q is essentially equivalent to h and correlated to both the in-plane and out-of-plane constraints, whereas A2 is more suited to characterize the in-plane constraint.