Flyover structure

from Wikipedia, the free encyclopedia
Two double-track lines combine to form a four-track line in one- way operation with the help of a flyover structure (here left-hand traffic).

A flyover or crossing structure is a bridge , an underpass , an artificial cut in the terrain, a tunnel or another structure, the primary task of which is to guide two intersecting traffic routes on different levels , unplanned , over an intersection.

Rail transport

Overpass structure between Fellbach and Waiblingen

Overpass structures are often found in railway construction . They are also called unbundling there. The long braking and acceleration distances of rail vehicles make it necessary to run different tracks independently of one another. This is the case, for example, with mainline tracks that lead out of a station without leaving trains blocking the route for other journeys. Due to the flat access ramps, railway bridges are often very long structures. For example, the Wylerfeld unbundling in northeast Bern consists of a 300 m long tunnel with a ramp in front and behind, each around 290 m long.

Car traffic

Motorways with their completely crossing-free lanes also make a large number of flyovers necessary, for example at all motorway junctions or when connecting countries with left-hand and right-hand traffic .

Web links

Commons : Flying junctions  - collection of pictures, videos and audio files