The proverbial bridge between expertise in steel construction and artistic construction

Within the final design for the expansion of Air Traffic Control the Netherlands' building complex at Schiphol East, there is one element that stands out. It is the connecting bridge that will link the old building and the new building. The design came about in a construction team. Ector Hoogstad Architecten is responsible for the overall design. Octatube, as the driving force behind the aesthetics, elaborated the design technically in order to make it completely feasible. De Kok Staalbouw, together with Bouwcombinatie Sprangers-Kuijpers & Octatube, took on this challenging project.

The bridge itself is a work of art in itself: an architectural tour de force, consisting of oval, steel rings, with round tubes braced in between. The contract to build this complex steel structure went to De Kok Staalbouw, from Heerle in the province of Noord-Brabant. Who else has so much experience in manufacturing special steel constructions, where form, function and fit are completely in balance?

Some hefty challenges
We speak with Kees Hoendervangers, project manager at De Kok Staalbouw. "The first challenge involved in such a design is precision in dimensioning. There are very high requirements for that. The design requires a lot of welding, where the art is to anticipate the stretch and shrinkage that occurs during the welding process and to have the final product fall exactly within the set tolerances in terms of dimensions," Hoendervangers opens the conversation.

The second challenge was transportation. "We are talking about two bridge sections that had to be transported, to be put together on site. Each section 24 meters in length by a width of 6.1 meters and a height of 4.6 meters. Transport by water was the only option, but in order to ship from Heerle, a trip to Roosendaal had to be made first. To that end, part of the highway was closed. In the end, the two-part construction was transported by pontoon to Amsterdam."

A steel path through the treetop
"The bridge sections, after being put together, are hoisted in between the two buildings. The whole is supported by a steel tree with four large branches. This tree will be between the bike path and the car lane. First, the whole will now be covered with glass, cladding and floorboards. When everything is ready in May, the crossing will be fully air-conditioned and covered," says Hoendervangers in conclusion.