Issue 70

D. Kosov et alii, Frattura ed Integrità Strutturale, 70 (2024) 133-156; DOI: 10.3221/IGF-ESIS.70.08

(a) (b) Figure 9: Single-edge-notched shear test: (a) boundary conditions and geometry, (b) finite element mesh.

(a) (b) Figure 10: Load-displacement curves for different loading direction for (a) elastic and (b) plastic solutions.

The load-displacement curves for two branches and one inclined cracks are depicted in Fig.10. Despite the differences in crack growth trajectories, the behavior of the load-displacement curves is close to each other and shows moderate descent of the load in the post-critical regime with respect to mode I elastic solution (Fig.8a). The fracture patterns at several loading stages are visualized in Fig.11 for single-edge-notched plate subjected to shear test and are in good agreement with the results reported in the literature [2, 4, 6].

(a)

(c)

(b) (d) Figure 11: Single-edge-notched shear test. Crack patterns for  =0 ˚ are depicted on the left-hand side at the deformation state: (a) u =0.008 mm; (b) u =0.0125. Results obtained for  =7 ˚ are given on the right-hand side at the deformation state: (c) u =0.007; (d) u=0.0115 mm. A comparison of phase field fracture fields as a function of applied force direction indicates that the deviation of the crack angle from  =0 ˚ to  =7 ˚ has sufficient effect on the damage fields or crack trajectory. It should be noted that the state of initial pure shear in fracture mechanics is characterized by extreme instability in the sense of the direction of possible

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