Sauer Valley Bridge (Wasserbillig)

The Sauer Valley Bridge is a motorway (Autobahn) bridge high above the Sauer River which at this point marks the frontier between Luxembourg and Germany. It was constructed between 1984 and 1987.

The bridge is 1195 m long and, at the lowest point of the valley, 98 m above the valley floor. Viewed from above it is formed as a curve with a radius of 2000 m. Additionally, the road surface has a constant 1% gradient. The girder bridge was built with a single superstructure for both carriage ways, and is positioned approximately a kilometer to the north of Wasserbillig in Luxembourg.

Superstructure
The bridge has a steel superstructure of a constant level underpinned by a continuous support. The longest span between support pillars is 150 m, which is the span crossing the river. On the Luxembourg side, traveling from west to east, the other span widths are 75 m, 90 m and 125 m.  Two more spans on the German side are of 90 m and 75 m.

The lateral profile of the bridge deck comprises a single box section 27 m and an Orthotropic deck inclined at 3.8%. The horizontal profile of the support floor is 8.87 m wide. There is therefore a difference between the thicknesses of the two sides of the bridge support which is 5 m on the inner side of the road's curvature, and 5.34 m on the outer side.

Construction
Construction of the superstructure took place in 68 section. Each section was delivered as eight segments. The steel of the superstructure used the incremental launch method, employing a machine using 21 pushing devices. In order to be able to use this method over the long spans of the bridge without the need for temporary supports from below, a 58 m high cable bearing moving pylon was employed, mounted on the road deck and set 120 m back from the tip of the slowly advancing structure.