Autobahn A24, Noise-Protection Wall at Exit Hamburg-Jenfeld

Noise-Protection Wall-Bridge - 22 m Span, Elevation Resident’s view Client: Freie und Hansestadt Hamburg, Germany Behörde für Bau und Verkehr Abt. Brücken- und Ingenieurbauwerke Construction Costs: 3.5 million € Services: General and structural design, technical check and approval of Documents for Construction Period: 2002 - 2004

The noise-protection wall project at the A 24 Exit Hamburg-Jenfeld was constructed as a later noise provision. The project consists of the construction of active noise-barrier facilities and additional passive noise-protection at the north and south side of the existing Highway.

As part of the project, the construction of absorptive noise walls north and south of the A 24 became necessary as well as noise-barrier bridges as bearing structures for foot ways, roads and streams which are crossed by the Highway A 24.

As load bearing structure for the noise-barrier bridges high-placed multispan crossbars, as part of steel frame structures, have been designed and are made of tubular steel beams. The panels are fixed to the crossbars on cantilevered frames. The panels are sound absorptive on one side or both sides, highly-absorbent at the lower part and transparent at the upper part.

The toe anchorage of the steel posts is made in concrete, under which a local concrete bored pile is arranged as deep foundation in each case. The bored in-situ concrete piles are ?1.0 m for the noise-barrier bridges. The total length of the five noise-barrier bridges is 195 m.

The absorptive noise walls are essentially a post and panel system. Vertical steel posts are anchored to the ground using 0.7 m diametre bored piles. The pre-cast concrete panels span horizontally between the posts and rest directly on the footings supported by pre-cast plinths. The noise wall is sound absorptive on both sides. The total length of the absorptive noise walls is 1680 m. The maximum wall height of 6.50 m has been constructed.