SPECIAL BRIDGE AWARD

The Netherlands

Schuttebusbrug

looking wavy elegant and light requires extraordinary engineering skills

^{Photo: ipv Delft / Henk Snaterse}

The finesse of this edgy steel bridge is captivating. The new traffic mark adds with an elegant S-shape, shiny metallic painting of the main beam and classy bamboo cladding of the deck a playful aspect to an otherwise busy urban space. What looks so wavy elegant and light requires extraordinary engineering skills to design for torsional strains and to build for heavy traffic loads above the rail tracks.

With the bridge, named after the old Schutte Bus company, buses go over the tracks between the new bus stop and the train station. Passengers have a good view on the tracks whilst the bridge also contributes to the beauty of the public space: It swings like a canopy over the track and the adjacent green zone.

High-quality bamboo cladding on the underside of the bridge deck forms a wooden ceiling, which fits well with the city park. Together with the S-shape, it gives the bridge its character.

^{Photo: ipv Delft / Henk Snaterse}

The structure is made of a box girder with cantilevers resulting in three lines: the dark gray steel girder, the wooden lamellae above it and the edge line. The columns are placed eccentrically on ei-ther side of the track. They seem to be in-clined and surfaces are bevelled to fit the design of the bridge deck. All kinds of facilities are integrated in the edge of the bridge.

The torsion-resistant design makes the slender appearance of the 245-meter-long bridge seem to float. The main S-shape span of about 80 m over the track is a steel box girder with cantilevered steel wings. On top is a concrete layer forming a composite deck. With a torsional rigid structure point supports are feasible and ensures a short span. The torsional mo- ment is transferred at the abutments. The main span is also connected to the access bridges with prestressing strands requiring heavy steel anchors. Weight and length of the concrete access bridges reduce the field moment in the steel structure. As steel and concrete structure flow into each other, the bridge is continuous aesthetically and structurally.

Limited space and train traffic were the main challenges for erection. The steel structure was produced in segments, transported to the site and assembled next to the railroad. The steel span was driven overnight on self-propelled modular transporters to final position placed on an auxiliary structure and fixed. After the access bridges were ready the parts were tied together.

The bus bridge not only connects the new bus station and the public transport route, but also the urban and landscape fabric of Zwolle and enriches the busy traffic area with unique shape and shine.

  
^{Photo: ipv Delft / Henk Snaterse}