Double deck bridge
A double-decker bridge is a structure that has two carriageway levels arranged one above the other. The upper deck can accommodate a multi-lane carriageway, the lower level can be open or closed as a tunnel for the opposite direction. There are also versions where the rail traffic runs below and the bicycle traffic on the outside of the tunnel. The reason for the construction of a double-deck bridge is to be seen economically, a long distance to be bridged for two traffic flows simultaneously over a body of water. Multi-storey bridges have the advantage that the statically necessary construction height is also used as a traffic area. Compared to single-story bridges, the dead weight of the double-decker bridge is reduced because the bridge width is smaller and the necessary cross members are lighter. A disadvantage is the more complicated threading of the access roads to the different bridge levels compared to one-piece bridges.
Construction
The height between the upper deck and the second level must be such that, on the one hand, high vehicles can pass through without problems, and, on the other hand, there is sufficient ventilation, provided that the variant is closed on the side. Then there must be a path for rescue workers or an escape route on the outside of the tunnel if an accident should occur in the corresponding tunnel segment. Access to the second level is usually from the side with an introductory curve and ends with an exiting curve, while the upper deck can be accessed directly.
Well-known double deck bridges
- Alf-Bullay double-decker bridge near Bullay : the Moselle section above , road traffic below
- Bay Bridge in San Francisco : pure freeway bridge
- Brooklyn Bridge in New York : above a central track for bike and foot, which forks at the “stone gate pairs”
- Chaotianmen Yangtze Bridge near Chongqing : Railway and road bridge
- Dreirosenbrücke in Basel : part of the north bypass, motorway below, street traffic with tram and pedestrian boulevard above
- Dumicketal bridge on the Biggesee : below the Biggetalbahn , above road traffic
- Georg-Danzer-Steg (also: U6-Danube bridge ) in Vienna : pedestrian and cycle path as a route suspended below the bridge structure in the bridge section over the New Danube
- George Washington Bridge in New York: road traffic
- I Street Bridge in Sacramento: Railroad and road bridge
- Listertal bridge on the Biggesee: below the Biggetalbahn, above road traffic
- Manhattan Bridge in New York: railroad and road bridge
- Niagara Falls Suspension Bridge : former rail and road bridge
- Nuselský most in Prague : the Prague metro runs in the hollow box of the concrete structure
- Oberbaumbrücke in Berlin : above subway, below road traffic
- Oberhafenbrücke in Hamburg : above rail, below road traffic
- Øresund Bridge : above car traffic, below rail traffic
- Prater Bridge in Vienna: Lateral routes upstream and downstream below the roadway for motor vehicle traffic, each attached next to the underside of the bridge box girder
- Ponte 25 de Abril in Lisbon: road traffic above, rail traffic below
- Reichsbrücke in Vienna: above motor vehicle traffic; Below is the underground line (enclosed by the reinforced concrete load-bearing box) and outside shared bike and footpaths on both sides, each covered by the lane above and connections to the Danube Island
- Stubenrauchbrücke over the Teltow Canal in Berlin-Tempelhof : road traffic above, Ullsteinstraße underground station below
- Tsing Ma Bridge in Hong Kong : road traffic above, rail and road traffic below
- Verrazzano-Narrows Bridge in New York: pure motorway bridge
