Issue 49

B. El-Hadi et alii, Frattura ed Integrità Strutturale, 49 (2019) 547-556; DOI: 10.3221/IGF-ESIS.49.51 553 exceeded for other configurations (fig. 8.a). On the other side, fig. 8.b shows that the maximum value of the stress intensity factor increases with the growth of the angle and is located inside the front of the crack. Figure 8 : Distribution of the Von-Mises stresses (MPa) in skew crack front. Figure 9 : Stress intensity factors along skewed crack front for different thickness. (a) t=2.29mm (b) t=6.35mm. Consequently, this explains the crack shape in the fig 10.a where it is clearly shown that the maximum length of the crack appears in last point crack front of the free side of the panel and this makes it compatible with stress intensity factor distribution results. Figure 10 (a) Crack-front shape obtained from fatigue crack propagation of repaired plates (b) Comparison of normalized crack-front shapes between repaired panels with 2.29 mm and 6.35 mm thickness [27]. Fig. 9 shows the distribution of the stress intensity along the crack front for the thick panels where it can be observed a shifted of maximum value from the free side of the plate towards the patched side. Accordingly, the maximum value is