Versuchsbasierte Ermüdungsfestigkeit von Konstruktionsdetails mit Radlasteinleitung - Untersuchungen an nicht durchgeschweißten Flansch-Steg-Verbindungen

Test-based fatigue strength of constructional details with wheel load application - Investigations on partial penetration flange-to-web connections.

In case of bridge cranes, the wheel loads are applied to the supporting crane runway girders through their top chords. The constructional details of the top-chord region, i. e. the joints and connections, are subjected to a multiaxial stress state due to the wheel load introduction and the global bending of the crane runway girder. For welded crane runway girders, the flange-to-web connection is one of these constructional details and subject of this article. The frequent travelling of wheel loads over a crane runway girder leads to a multiaxial fatigue stress due to the concentrated load introduction and the notch effect of the constructional details. As the multiaxial fatigue stressing exhibits a phase shift between the stress components, it is referred to as nonproportional. The fatigue strengths of Eurocode 3 being necessary for the fatigue evaluation were derived in analogy with the tension-loaded cruciform joint and are not test-based for the considered constructional detail. In the IGF research project FOSTA P895, the fatigue strength of partially penetrated flange-to-web connections were determined through a combination of fatigue tests on crane runway girders with travelling and stationarily pulsating wheel load. The project aimed at a more reliable evaluation of the nonproportional multiaxial fatigue stress of the flange-to-web connection.