Issue 49

D. E. Belhadri et alii, Frattura ed Integrità Strutturale, 49 (2019) 599-613; DOI: 10.3221/IGF-ESIS.49.55

The behavior of the K III

along the crack front is shown in Fig. 12 (A)for different values of (a). The median position of the . On the other hand, and as already pointed out, this variation becomes progresses proportionally as a function of depth (a). Fig. 12 (B) asserts that K III reaches

crack is not sensitive to the variation of the K III

more and more marked where K III

maximal values at the outer limit of the elliptical crack.

Figure 12: variation of K III pipe with c = 60mm.

along the front for different crack depth (A) variation of K III

for position (4) of the crack (B). Repaired

, K II

and K III

along the crack front for different length. Repaired pipe with a = 7mm

Figure 13: variation of the SIF: K I

A second analysis is presented in the following for a constant depth a = 7mm and we change the length of the crack 2c. In these results it was found that the three stress concentration factors keep almost the same behavior noticed for the depth a with respect to the crack length 2c. The appearance of the K I shows the presence of three zones, the K II is independent

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