| Abstract: | Developments of steel‐composite bridges – motorway bridges with one‐piece composite cross‐sections. On design orders of the German Bundesministerium für Verkehr, Bau‐ und Wohnungswesen (BMVBW) motorway bridges have to be built with two superstructures – one for each carriageway. To get satisfying solutions in design of motorway bridges across valleys too, the authority decided in 1997 that it should be possible to build one‐piece steel‐composite bridges, provided that special suppositions are respected. The acceptance based on the condition, that it is possible to repair the reinforced concrete slap of the one‐piece superstructure as well as separated superstructures. The extensive maintenance of traffic has to be guaranteed all over the repair period. Since 1997 DEGES erected six bridges with one‐piece steel‐composite cross‐sections, three further bridges are under construction. Although the superstructures are designed for the state of the partly replacement of the reinforced concrete slap and therefore they are over dimensioned for the using‐state, these one‐piece superstructures are economic if they have a height of more than 50 m over the bottom of the valley. The following essay describes the one‐piece steel‐composite cross‐sections and gives constructive hints to their components. |
