Realistic Finite-Element Model For The Double-Torsion Loading Configuration

The analytical approach to the double-torsion, constant-displacement-configuration technique has forced a strong oversimplification of the specimen model, and, therefore, of the strain field in classical applications. For this study, accurate three-dimensional finite-element analysis was performed on a realistic specimen; that is, one with thickness, a groove, and an initial notch. The influence on the strain-energy release reate of the specimens width and length, fracture length, the presence and shape of the side groove, the presence of an initial notch, and the curved shape of the fracture front was estimated from this analysis. Significant deviations from the classical analytical solution were found.