PSI - Issue 75

Bruno Depale et al. / Procedia Structural Integrity 75 (2025) 254–261 Bruno Depale/ Structural Integrity Procedia (2025)

260

7

• Two detail classes (DCs) are given in the Eurocode 3 background document (2005): DC71 for one-sided riveted joints and DC90 for double-covered riveted joints, but no value is given in current EN1993-1-9. • Previous DC71 is confirmed by joint report EUR 23252 (2008, § 3.5.2). • Bertolesi et al. (2021) suggest that a variable DC between 63 and 71 MPa should be selected for bridge crossbeams riveted details. • Pedrosa et al. (2019) works result in a DC = 55 MPa for one-sided riveted shear connections and DC around 80 MPa for double-sided riveted joints. For other structural details, we shall refer to EN 1993-1-9. In accordance with macho et al. (2019), the corrosion effect is considered by multiplying the fatigue strength of the relevant structural details by a factor c R,95 , defined by: ,95 = 1 − 0,9954 ∙ (3) where d A is the level of corrosion determined as the change in cross-sectional area. 5.3. RLA of Long Bien Bridge The results of the calculation of the cumulative damage D are summarized in Table 2 for the three most critical structural details, by applying the movable loads described in 3 and the counting Rainflow method.

Table 2. Cumulative fatigue damage D for three critical details.

Detail A

Span Nr. 2

Upper chord

DC71

Stress range i (MPa) 98,412

Number of stress cycles n i

Number of cycles to failure N i

Damage D i

250 000

500 000

0,5

…

…

…

…

Total damage D

2,1

Detail B

Span Nr. 2

Lower chord

DC71

Stress range i (MPa) 85,228

Number of stress cycles n i

Number of cycles to failure N i

Damage D i

250 000

500 000

0,5

…

…

…

…

Total damage D

2,1

Detail C

Span Nr. 3 Stress range i (MPa) 128,836

Upper chord

DC71

Number of stress cycles n i

Number of cycles to failure N i

Damage D i

250 000

500 000

0,5

…

…

…

…

Total damage D

2,1

The above mentioned three critical details A to C are represented in Figure 6.