During upgrading of the A1 Autobahn near Cologne, noise abatement measures to protect local residents was a special concern. This involved the A1 near Lövenich being covered by an artificial tunnel - known technically as a noise abatement enclosure (NAE) - for a distance of approximately 1.5 kilometres.
With a volume of around 150 million euros the LEH project is more economical than a conventional tunnel. Integrated in the up to 24 metre wide tunnel are the Lövenich junction and five bridges crossing the Autobahn. This junction is unique in Germany. The up to seven metre high concrete walls are covered by a more than 30,000 square metre steel-glass roof structure. One thousand five hundred two-and-a-half tonne window elements are integrated in the roof.
The two tubes should be completely opened by the end of 2013 at the latest. The population of Cologne will then enjoy a noise abatement structure that sets and meets the highest of standards and considerably enhances the residents' standard of living.
JORDAHL provided JDSD double shear connectors for the LEH project. They effectively prevent differential deformation of the roof truss.