620 Ingenieurwissenschaften
Filtern
Dokumenttyp
Volltext vorhanden
- nein (9)
Gehört zur Bibliographie
- ja (9) (entfernen)
Schlagworte
- Verbundbrücke (9) (entfernen)
Institut
Im Zuge der Hochwasserschutzmaßnahmen entlang der Salzach wird für die Überführung der Straße von Zell am See nach Kaprun eine neue Brücke mit größerer Stützweite notwendig. Der Ersatzneubau dieser Brücke über die Salzach ist ein Trogbauwerk in Verbundbauweise. In Querrichtung werden π-Platten mit externer Bewehrung gewählt, um eine große Schlankheit und eine schnelle Bauzeit zu ermöglichen. Die externe Bewehrung der Platten wird feuerverzinkt ausgeführt.
Integral bridge with RS-Overpass technology : step into the future of standard highway overpasses
(2023)
Starting from Germany, the VFT bridge girder technology (prefabricated composite beam) has spread in several European countries in the last decades as further development of the standard steel-concrete composite solution. Its configuration fits perfectly to integral frame bridges built over existing infrastructure with the scope to minimize the traffic disturbance. In this paper a further development with the focus on cost efficiency in span ranges of 40-55 m is proposed: the RS-Overpass technology. The change consists in using standard rolled sections by adapting them into the integral frame bridge configuration, further enhancing the structural efficiency with the benefits of high-steel strength. The constructive details to achieve the polygonal form have been studied to allow easy fabrication and a maximal clearance height over highway traffic lanes. The RS-Overpass solution is conceived as the economic option of standard highway overpasses, with the aim of a overall construction cost reduction of 5%. The possibility of weathering steel or hot-dip galvanization create the unique offer for a maintenance-free solution.
The introduction of composite dowels (CDs) in Europe at the beginning of the last decade led to the creation of new forms of composite bridges in which a T-profile is used instead of an I-beam. Both the construction and design methods are new [4]. Experiences from the construction of new bridges and discussion between the authors lead to new significant conclusions, which should be included in the new European approval (CEN-TS). The problem of design formulas for concrete dowels is presented.
Composite dowels have opened new possibilities for engineers designing composite structures. The fundamental and most important characteristic of composite dowels is the shape of the cutting line. It is important to understand why only one particular shape of the cutting line is used in bridge engineering, while so many different shapes have been investigated by many researchers. The essential part of the process of developing composite dowels – the development of the shape of the cutting line – is presented in this paper. The influence of the steel web thickness is presented, and technological problems of steel fabrication are highlighted. The role of empirical experience from the first bridges, push-out tests, and finite element simulations is presented. Assumptions for numerical procedures are given. The distinction between the steel failure and concrete failure modes is introduced for composite dowels. The paper presents how the concept of “shape” was divided into “shape,” “ratio,” and finally “size,” and how, because of the fatigue problems in bridges, all the three factors have emerged to result in the form of shapes that can satisfy the requirements for bridges. Research leading to the invention of the first version of the clothoidal shape is presented.
Roads overpassing highways or speedways are rather a common case, as such bridges occur in average every 2 km of highways in densely populated areas. Due to the high number and similar boundary conditions, the design and realization tends to be standardized and repetitive. The total length ranges mostly between 40 and 55 m, whereas the construction height is a limiting factor since minimumclearance heights must be guaranteed both for safety as well as for driving comfort. Due to these reasons, highway overpasses have been a field of application where steel-framed composite decks have proventheir efficiency for this task. Starting from Germany, the VFT technology (prefabricated composite beam) has spread in several European countries in the last decades as further development of the standard steel-concrete composite solution. Its configuration fits perfectly to integral frame bridges built over existing infrastructure with the scope to minimize the traffic disturbance. In this paper a further step is proposed: the VFT-RS technology. The change consists in using standard rolled sections by adapting them into the integral frame bridge configuration, further enhancing the structural efficiency with the benefits of high-steel strength. The possibility of weathering steel or hot-dip galvanization create the unique offer of a maintenance-free solution.
Starting from Germany, the VFT® bridge girder technology (prefabricated composite beam) has spread in several European countries in the last decades as further development of the standard steel-concrete composite solution. Its configuration fits perfectly to integral frame bridges built over existing infrastructure with the scope to minimize the traffic disturbance. In this paper a further development with the focus on cost efficiency in span ranges of 40-55 m is proposed: the VFT-RS technology. The change consists in using standard rolled sections by adapting them into the integral frame bridge configuration, further enhancing the structural efficiency with the benefits of high- steel strength. The constructive details to achieve the polygonal form have been studied to allow easy fabrication and a maximal clearance height over highway traffic lanes. The VFT-RS solution is conceived as the economic option of standard highway overpasses, with the aim of an overall construction cost reduction of 5%.
This paper introduces (both formally and technically) a new concept: a hybrid steel–concrete cross section. The definition is based on the shear force transmission mechanism and it assumes the existence of a new type of shear connections, i.e. composite dowels. The hybrid cross-section is a generalization of composite steel-and-reinforced concrete cross sections and it is defined by a new way of dimensioning for vertical shear. The hybrid cross section concept is based on a specific approach to the lever arm of internal forces and an assumption that the local shear transfer mechanism of composite dowels is different than in the case of classic welded studs. The concept makes it possible to show by design calculations that the shear force is transferred through jointly the concrete part and the steel part. It is worth emphasizing that the proposed concept is a response to the new opportunities provided to engineers by composite dowels and to the fact that the bridge structures designed nowadays are different from the ones designed previously. The concept enables the design of completely new types of composite steel–concrete beams. The presented theoretical analyses verified by means of FEM show how the change of the shear connection level influences the division of the shear force in the cross section. This is included in the design concept through the internal lever arm of the hybrid section. The proposed concept has been shown to be internally consistent and complete.
Im Zuge der Hochwasserschutzmaßnahmen entlang der Salzach wird zur Überführung der Straße von Zell am See nach Kaprun in Österreich eine neue Brücke mit größerer Stützweite notwendig. Der Ersatzneubau der Brücke über die Salzach bei Mayereinöd ist ein Trogbauwerk in Verbundbauweise, dessen Form funktional entworfen wurde. In Querrichtung werden vorgefertigte π-Platten mit externer Bewehrung gewählt, um eine große Schlankheit und eine schnelle Bauzeit zu ermöglichen. Die externe Bewehrung wird feuerverzinkt ausgeführt.