Deutz Suspension Bridge (Cologne)
The Deutz Suspension Bridge (Deutzer Hängebrücke) crossing the Rhine in central Cologne, was a self-anchored suspension bridge using eyebar chains. It was built from 1913 to 1915.
n February 28, 1945, the bridge, heavily burdened by refugees and military vehicles, and undergoing war damage repair, suddenly collapsed. An eyebar is preserved on the left bank of the bridge. At the end of the war, the temporary 'Lt.Gen. Lesley McNair Bridge' served as a temporary bridge next to the destroyed suspension bridge.
Today's bridge structure was rebuilt just two years later, between 1947 and 1948. 'The world's first steel box girder bridge' was designed by Fritz Leonhardt and built by GHH Oberhausen AG. It was inaugurated on October 16, 1948.
Between 1976 and 1980, a second bridge with the same profile was designed and built upstream as a prestressed concrete structure by the Basel engineers E. and A. Schmidt. In an operation that took several days, the new twin bridge was pushed close to the old steel bridge so that the tram had its own two-track track between the two-way lanes.
The externally visible web surface was structured with vertical ribs and a flange at the bottom in order to match the appearance of the steel structure. However, due to the lack of benefit for the durability of the concrete, it is the only Rhine bridge in Cologne that is not painted green.
Since the reinforced concrete box with a rectangular cross-section does not contain any internals, it forms three accessible rooms (without daylight) with curved floors and varying room heights. These rooms are often used for art installations, exhibitions as part of the furniture fair and for concerts.
The above information is condensed from the German Wikipedia entry.