Wupper River Valley Bridge: A State-of-the-Art Composite Bridge

The German Autobahn A1 motorway is one of the nation's most important and frequently traveled highways, connecting the country's northern and southern regions. The road currently has two lanes in each direction, which do not provide enough capacity to carry the traffic volume without daily traffic jams and heavy delays. Therefore, the federal government and the Northrhine-Westfalia Department of Transportation decided to ease the situation by adding one lane in each direction. This total of six lanes fits into the master plan of widening major highways around the Ruhr River region. North of Cologne, the Autobahn A1 crosses mountainous terrain, so several bridges with total lengths between 240 and 420 m (non-ISO measurements 790 and 1,380 ft.) have had to be widened, replaced, or, most commonly, supplemented by a new bridge. Such supplementation was used on the Wupper River Valley bridge, called "Oehde," close to the city of Wuppertal. The Oehde Bridge supplementation is a case study that illustrates the current state-of-the-art of composite bridges in Germany.