Bendahler Straße

This railroad bridge, with four distinctive superstructures, crosses Bendahler Straße in the German city of Wuppertal.

This project was the first to use a new design based on the classic trough bridge. The design was developed by the German Railroad authority as an alternative to conventional concrete-frame bridges.

Concept

Four rail lines are carried by four distinctive superstructures formed by a typical trough structure in a simple span length of about 16 m. The total construction length is about 17.8 m. The bridge was designed to maximise the headroom under the bridge and to enable efficient erection.

Key benefits of using steel

The key benefits of this type of bridge are:

• Low construction noise through avoidance of common cross-beams and the large mass of the bottom plate.
• Reduction of the girder height by usage of the bottom plate to 950 mm (+ 100 mm bottom plate).
• Optimum design of the supports mean that rail traffic speeds of up to 160 km/hour are possible across the bridge

Design details

The bridge is formed by four troughs with 100 mm thick upper flanges welded from two 50 mm thick plates and 20 mm thick webs stiffened at a distance of 1,000 mm. The bottom of one trough is created from a unique 100 mm thick plate, 3,400 mm wide and 13,100 mm long, in the middle. 70 mm thick plates were welded next to the supports. The angle between the web and bottom plate is 114°. Inspection gangways are installed at the left and right side of the entire bridge.

Construction details

The bottom plates were cut to shape by the steel mill. The four troughs were made entirely in the workshop and then transported to the site. They were brought in to position by a mobile crane.

Summary