PSI - Issue 82

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Kübra Polat et al. / Procedia Structural Integrity 82 (2026) 267–273 K. Polat, M. M. Topaç/ Structural Integrity Procedia 00 (2026) 000–000

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Centre of axle beam Mitigation Zone H !

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Mitigation zone

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Model 3

Hole 1 Hole 2 Hole 3

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Model 2

Model 4

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Fig. 5. Different hole forms and the axle beam designs created using these forms.

Analysis results show that the elliptical hole model (Model 3) has the lowest stress and reduces mass by approximately 6.6%. The four-spring hole model (Model 4) has a similar stress level to Model 3, but reduces mass by approximately 8%. According to the results, Model 4 is the most suitable design in terms of both weight reduction and strength. The potential for holes on the axle beam to cause a new failure mode was investigated by comparing the stress values of the reference part which meets all design requirements. The results showed that the maximum stresses in different hole shape models were lower than those in the reference, indicating safe stress levels for the axle beam. The stress types around the holes were also examined. Crack propagation perpendicular to the maximum tensile stress is a critical stage in fatigue failure (Eryürek, 1993). Analyses were showed that the maximum stress regions were subjected to tensile stress. Stress values and types are shown in Fig. 6. These maximum stress values were evaluated using the Goodman-Haigh approach and it was examined whether they were in the infinite life region. ! !

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Hole 1

Hole 3

Hole 2

Hole 1

Hole 2

Hole 3

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High stress concentration

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Tensile

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Hole 1

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Hole 3

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High stress concentration

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Model 4 Hole 1 Hole 1 Compressive

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Fig. 6. Analysis results of the axle beam designed with different hole geometries.

4.3. The fatigue life evaluation according to the Goodman–Haigh approach Predicting the fatigue life of components such as the front axle, which operate under variable loads caused by road irregularities, is crucial for vehicle safety and structural integrity. The widely used Goodman–Haigh approach relates