PSI - Issue 77

L.A.S. Maia et al. / Procedia Structural Integrity 77 (2026) 87–94 Maia et al. / Structural Integrity Procedia 00 (2026) 000–000

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stresses were located at the adhesive boundaries, between 4.2 to 5. In the DP8005+XNR6852E-2 joint, peak τ xy stresses occurred at the adhesive boundaries, and increased as β decreased, except for β =15°. Using the model with no chamfer ( β =90°) as a reference, τ xy stress distributions of the joint significantly improved with decreasing β .

4

2.0

3

1.0

2

σ y / τ avg

τ xy / τ avg

0.0

1

-1.0

0

0

0.2

0.4

0.6

0.8

1

0

0.2

0.4

0.6

0.8

1

x / L O

x / L O

a)

b)

7,5º

15º

30º

45º

60º

90º

7,5º

15º

30º

45º

60º

90º

Fig. 6. Normalized τ xy (a) and σ y (b) stresses for the DP8005+AV138 joint (inner chamfer effect).

For the DP8005+AV138 joint, the 7.5° model exhibited the highest peak σ y / τ avg stresses (Fig. 6 b), at the outer boundary of the adhesive, ranging from 1.7 to 2. Among all models, β =45° provided the best overall performance. Due to the weak properties of RTV106, it was not possible to simulate the RTV106+AV138 joints with β =7.5° and 15°. In the remaining models, no noteworthy σ y stresses were observed in the sections where RTV106 was used, while σ y stresses peaked at the adhesive boundaries. Although the model with no chamfer showed slightly lower σ y stress than other models at one boundary, it also exhibited peak values approximately 30% higher at the opposite boundary. For the DP8005+XNR6852E-2 joint, peak σ y stresses were observed at the outer adhesive boundary in the no-chamfer, β =7.5°, and β =15° models. The remaining models showed decreasing σ y peak stresses with decreasing β . 3.3.2. Joint strength Fig. 7 (a) presents the P - δ behavior of the DP8005+AV138 joint. β =7.5° presented the lowest P m (12.77 kN), corresponding to δ =0.493 mm. U for β =7.5° was 3.20 J, 28.4% lower than that for β =90°. For the RTV106+AV138 joint, simulation was not feasible for β =7.5° and 15°. The β =30°, 45° and 60° models withstood slightly higher P m compared to β =90°. The best performance was displayed by β =30°, with P m =11.20 kN. However, U by the latter model was 1.1% lower than that for β =90°. The DP8005+XNR6852E-2 joint is the strongest. The β =45° and 60° models presented the best results, and the performance of remaining models decreased with decreasing β . The β =60° model sustained the highest P m (26.31 kN), corresponding to δ =0.718 mm and U was 2.7% higher than for β =90°.Fig. 7 (b) represents the effect of the inner chamfer on P m . The DP8005+XNR6852E-2 joint was most affected by this alteration ( P m / P 90º reduction up to 29.6% for β =7.5º), but not positively. This negative effect was highest for β smaller than 45°, and was also found on the DP8005+AV138 (up to 12.8% for β =15º), but with a lower magnitude. For the RTV106+AV138 joint, the study was not completed up to the smallest β , due to the excessive RTV106 flexibility.

10 12 14 16

0 2 4 6 8

P m /P 90 °

P [kN]

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0°

15°

30°

45°

60°

75°

90°

β

δ [mm]

a)

b)

RTV106+AV138

DP8005+AV138

DP8005+XNR6852E-2

7,5º

15º

30º

45º

60º

90º

Fig. 7. P - δ behavior of the DP8005+AV138 joint (a) and normalized P m (b) for different α .