PSI - Issue 66

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

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

to H1 is 62% at H3 and 66% at H4 at a crack length of 40mm and 38 mm respectively. H5 shows the most significant decrement among all locations, with a 70% reduction in effective SIF relative to H1 at both 38 mm and 40 mm crack lengths. Beyond this crack length, the percentage decrement of effective SIF at all holes location gradually decreases. In view of this, all further discussions of effective SIF with varying load ratios shall focus on the crack at H1, as this location is identified as the most critical in the left part of the strap plate.

Hole ‐ 3

Hole ‐ 4

Hole ‐ 5

20% 30% 40% 50% 60% 70% 80% % decrement in effective SIF w.r.t Hole ‐ 1

25

30

35

40

45

50

55

Crack length (2a) in mm

Fig. 4. % decrement of K_effective w.r.t Hole-1 of crack_tip-1 under Load Ratio-1

3.2. Variation of Effective SIF under Different Biaxial Load Ratio at Hole-1 The effect of four different in-plane tension-tension biaxial load ratios on the SIF at the H1 location is studied. Fig. 5 shows the variation of effective SIF with increasing crack length under bi-axial load ratios of 1, 0.75, 0.5, and 0.25. For a load ratio of 0.75, the SIF distribution with crack length for both crack tips is similar to that of load ratio 1. At load ratios of 0.5 and 0.25, the SIF distribution with crack length resembles that observed at H4 and H5 under load ratio 1. For all load ratios, both crack tips at Hole-1 exhibit similar behavior.

Load ratio ‐ 0.75 Load ratio ‐ 0.25

Load ratio ‐ 0.5

Load ratio ‐ 1 Load ratio ‐ 0.5

Load ratio ‐ 0.75 Load ratio ‐ 0.25

0% 10% 20% 30% 40% 50% 60% 70% 80% 90%

1000 1200 1400

% change in effective SIF w.r.t load ratio ‐ 1

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

30

40

50

30 35 40 45 50 55

Crack length (2a) in mm

Crack length (2a) in mm

Fig. 5. Variation of K_effective at Hole-1 under different load ratio

Fig. 6. % decrement of K_effective at Hole-1 w.r.t load ratio 1