PSI - Issue 66

Akash Shit et al. / Procedia Structural Integrity 66 (2024) 247–255

254

8

Shit and Prakash/ Structural Integrity Procedia 00 (2025) 000–000

34 mm. In the Case-1 configuration, an increase in SIF is observed at crack length of 32 mm, 38 mm, and 40 mm, while a reduction in SIF is observed at 34 mm and 36 mm crack lengths.

a

b

c

Fig. 8. (a) Case-1 (b) Case-2 (c) Entire model Fig. 10(a) shows that at crack tip 2 of the primary crack, the Case-1 shadow crack configuration consistently increases SIF at all five crack lengths except at 38 mm. On the other hand, the Case-2 configuration results in a relatively significant reduction in SIF between 34 mm and 38 mm crack lengths. . a b Without shadow Crack CASE ‐ 1 CASE ‐ 2 CASE ‐ 1 CASE ‐ 2

‐ 3,00% ‐ 2,00% ‐ 1,00% 0,00% 1,00% 2,00% 3,00%

1000 1200 1400

% decrement of K_eff w.r.t without shadow crack

0 200 400 600 800 K_effective, MPa.mm^0.5

30 32 34 36 38 40 42

32 34 36 38 40

Crack length (2a), mm

Crack length (2a), mm

Fig. 9. Due to the shadow crack at Hole-2 and Hole-3 (a) Comparison of effective SIF at crack tip-1 of Hole-1 (b) % difference in effective SIF at crack tip-1 of Hole-1 w.r.t the absence of shadow crack at Hole-2 and Hole-3 The percentage decrement of the effective SIF at crack tip-1 and crack tip-2 of the primary cracks, with respect to the absence of shadow crack at row-2, is plotted in Figs. 9(b) and 10(b), respectively. Figure 9(b) shows that at crack tip-1 of Hole-1, the maximum reduction in SIF is 2.32% with Case-2 at a 40 mm crack length, while the maximum increment is 2.18% with Case-1 at the same crack length. In Figure 10(b), at crack tip-2 of Hole-1, the maximum reduction in SIF is 3.16% with Case-2 at a 38 mm crack length, whereas with Case-1, a 2.99% increment is observed at 40 mm crack length. Based on this study, Case-2 is found to be more effective than Case-1 in reducing the SIF at primary cracks.