PSI - Issue 57

Jacques BERTHELLEMY et al. / Procedia Structural Integrity 57 (2024) 872–903 J. Berthellemy / Structural Integrity Procedia 00 (2023) 000 – 000

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Figure 16: Bridge of the Vistula River with strong fatigue resistant features (Photos W. Lorenc)

This innovative steel concrete composite arc shape of Figure 16 can be associated with the hangers made of two plates forming a cross of Figure 17. The conception of this type of hanger is also related with their high fatigue resistance associated with a low cost. These hanger also offer a resistance in compression [27], in fatigue when the right feature of Figure 18 is used [28] and it has been shown in [29] that the specific tensioned hangercross geometry of Figure 17 is not at risk of fatigue inducing resonance under wind loading. I recommend anchoring the hangers to the side plates of the arches using vertical fillet welds, working in parallel shear, as this is cheaper and more reliable in terms of fatigue. The bottom plate is but welded to the I main girder beam though a rounded hole.

Figure 17 : Hangers of the Roboul Bridge with two plates forming a cross : fatigue resistance can be achieved at low costs Fig. 18: Upper attachment of a hanger

This method was used to evaluate the Stress Concentration Factor (SCF) for various types of hangers implemented for tied-arch bridges as those described in [28] and to evaluate the fatigue resistance of existing rounded gusset at Dancourt bridges [30] on a continuous four spans steel-concrete motorway composite box girder bridges.