A numerical study of T-stress in dynamically loaded fracture specimens

The objective of this paper is to study the evolution of T-stress in dynamically loaded fracture specimens. To this end, two-dimensional plane strain, elastodynamic finite element analyses of single edge notched (tension) specimens, and three point bend specimens subjected to time varying loads are performed. The T-stress is computed using an accurate and computationally efficient domain representation of the interaction integral. The results demonstrate that dynamically loaded specimens are subjected to a large negative T-stress during the early stages of loading as compared to that under static loading. The above phenomenon can satisfactorily explain the strong elevation in the dynamic fracture toughness at high loading rates, which has been reported in numerous experimental studies. (C) 2001 Elsevier Science Ltd. All rights reserved.