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

91

5

2

4

3

1

2

σ y / τ avg

τ xy / τ avg

0

1

0

-1

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

Fig. 4 (a) illustrates σ y / τ avg stresses for the DP8005+AV138 joint. At the outer region ( x / L O =0.00; 1.00), relative σ y / τ avg stresses decrease as α decreases. Joints with α =7.5° and 15° exhibited positive relative σ y stress, whilst the others experienced compressive stresses. For α =7.5° and 15°, peak σ y / τ avg stresses occurred at the adhesive boundaries, whereas for the remaining models, these were located at the exterior. Due to the significant difference in stiffness, the RTV106+AV138 joint exhibited the highest peak σ y / τ avg stresses. No σ y stress was observed in the RTV106 region. σ y / τ avg stresses for the DP8005+XNR6852E-2 joint are similar to the DP8005+AV138 joint. Joints with α = 7.5° and 15° exhibited positive relative σ y stress, whilst the others experienced compressive stress. 3.2.2. Joint strength Fig. 5 (a) presents the load-displacement ( P - δ ) behavior of the DP8005+AV138 joint. The model with α =7.5° sustained the highest P m (15.36 kN), corresponding to δ =4.93 mm. U in this model was 4.93 J, which is 10.3% higher than for α =90°. In terms of P m , the RTV106+AV138 joint performed the worst among all. The α =7.5° model also exhibited the best performance, with P m =12.42 kN, corresponding to δ =0.339 mm. This joint showed U =1.87 J, which is 4.5% higher than for α =90º. The DP8005+XNR6852E-2 joint proved to be the strongest, particularly the α =7.5° model ( P m =26.39 kN and δ =0.762 mm). This joint showed U =10.46 J, which is 16.4% higher than for α =90°.Fig. 5 (b) represents the effect of the outer chamfer on P m for all joints (P 90º is P m for α =90º). P m /P 90 º increased with α reduction for all joints, but the DP8005+XNR6852E-2 joint was the least affected ( P m / P 90º =1.3% for α =7.5º), whilst the RTV106+AV138 was the most affected ( P m / P 90º =14.6% for the same α ).

10 12 14 16 18

P m /P 90 °

0 2 4 6 8

P [kN]

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0°

15°

30°

45°

60°

75°

90°

α

δ [mm]

a)

b)

7,5º

15º

30º

45º

60º

90º

DP8005+AV138

RTV106+AV138

DP8005+XNR6852E-2

Fig. 5. P - δ behavior of the DP8005+AV138 joint (a) and normalized P m (b) for different α .

3.3. Inner chamfer effect

3.3.1. Stresses Fig. 6 (a) shows τ xy stresses in the DP8005+AV138 joint. Most of τ xy peak stresses occurred at the adhesive boundaries ( x / L O =0.17; 0.83). Peak τ xy stresses were also observed at x / L O =[0.38; 0.62] for β =7.5°, and x / L O =[0.31; 0.69] for β =15°. This joint exhibited τ xy / τ avg stresses up to 2 to 3.5. For the RTV106+AV138 joint, τ xy stresses could not be analyzed for β =7.5° and 15° due to the weak properties of RTV106. In the remaining models, peak τ xy / τ avg