Practice‐oriented design of tubular bracings in steel and composite bridges

In steel and composite bridges, the joints with slitted tubes and gusset plates that are usually used for tubular bracings inside or outside of box girders are under discussion due to their critically assessed fatigue behaviour. For the currently various design variants used in bridge construction with basically different notches, no clear rules are given regarding the detail category by the standards EN 1993-1-9 or EN 1993-2. The aim of the research project “Practice-oriented design of tubular bracings in steel and composite bridges” was the development of generally applicable rules to enable a more economical and safe approach for the design of steel and composite bridges. For this purpose, experimental investigations were carried out within the project on three different design variants of tubular bracings in order to determine the characteristic fatigue strength, which serves as basis for the proposal in prEN 1993-1-9. Further geometric parameters were numerically investigated and considered in the design and execution recommendations of the German RE-ING and BEM-ING.