Abstract
The focus of the project was the development of a practice-oriented and fatigue-suitable de-sign for diagonal tubular bracings by means of a connection between a slitted tubular element and gusset plate, as they are usually used inside or outside of box girders in steel and composite bridges. In German bridge construction, for example, different design variants are used with fundamentally different notches and those are not regulated by the standards DIN EN 1993-2 or DIN EN 1993-1-9. The relevance and necessity for the investigations was demon-strated by bridge structures that have been implemented or are in planning, such as the Schierstein Bridge, the Hochmosel Bridge and the Rinsdorf Bridge, where the construction detail was used in different versions. Project-specific investigations are expensive and not easily transferable to other bridge projects, and also there was a need for optimisation in manufacturing.
Based on the experimental investigations, three different design variants could be classified in notch detail categories, so that the fatigue verification by means of the nominal stress concept according to DIN EN 1993-1-9 is possible. A proposal was prepared for the new generation of the Eurocode prEN 1993-1-9 and has already been implemented in the final document. This proposal was also integrated parallel into BEM-ING Part 1-3 EC 3 "Steel Bridges", which will be published even before publishing of the future Eurocodes. On basis of the numerical investigations in this research project, further geometric parameters were worked out by derivation of notch factors in order to optimise the geometry for design recommendations such as the German design aids or bridge structure rules for steel and composite bridges, which are part of RE-ING and published by the Federal Ministry of Transport and Digital Infrastructure (BMVI). Based on the investigations, a proposal was made for the revision of the planning aids in which are detailed design rules for tubular bracings.
By implementing the results in the future Eurocode and German BEM-ING as well as in the planning aids of RE-ING, an economic and confirmed approach for the design and execution of steel and composite bridges was developed on basis of general rules. This results with clear design rules for structural engineering offices as well as for executing steel and compo-site bridge manufacturers, are leading to an improved design regarding the fatigue behaviour and durable bridges.
Research department
University of Stuttgart
Institute of Structural Design
Prof. Dr.-Ing. Ulrike Kuhlmann, Lisa-Marie Gölz, M.Sc.
Research funding
- BMWi
- DASt
- AiF
- Firmengruppe Max Bögl
- MCE GmbH
- Plauen Stahl Technologie GmbH
- AG der Dillinger Hüttenwerke
- Vallourec
- Ingenieurbüro Meyer+Schubart
- BMVI
Duration of the research project
01.02.2019 – 31.07.2021