ABSTRACT
For sustainable and economical infrastructures such as steel and composite bridges a practice-oriented and fatigue-suitable design is crucial. Cross girder bracings or box girder diaphragms are often realised with tubular elements especially with circular hollow sections (CHS) including a welded connection between the slitted tubular element and the gusset plate. The gusset plate welding at the end of the slit of the tube is the critical fatigue spot. For the currently different design variants used in bridge construction with basically different notches there is no clear rule given regarding the detail category by the standards EN 1993-2 or EN 1993-1-9. This paper summarises the results of the AiF-DASt research project on three different fatigue design solutions for tubular bracings in steel and composite bridges. An insight on the practice-oriented design, the benefits for the execution and manufacturing as well as the results of the experimental fatigue tests are given.
