Computational fracture analysis of different specimens regarding 3D and mode coupling effects

In this paper computational fracture analysis results for four different specimens are presented and discussed with regard to 3D and mode coupling effects. The specimens under consideration are a center cracked tension specimen, with a crack inclined to the loading direction, a single edge notch specimen under out-of-plane shear deformation, a quarter circular corner crack specimen subject to shear deformation and a three point bending specimen with a crack inclined to the mid plane between the supports. The numerical fracture analysis results are based on two different approaches. The stress intensity factor results are determined from the singular stress fields along the crack front and the strain energy release rate results are obtained by means of the modified virtual crack closure integral method. In all cases under consideration the computational results from the two different approaches agree very well. Furthermore, the agreement with the global behavior of the reference solutions is also good. However, significant deviations are found between the computational and the reference results regarding local 3D and mode coupling effects, which seem not to be covered sufficiently by the reference solutions available in stress analysis handbooks or the literature. (C) 2001 Elsevier Science Ltd. All rights reserved.