Flexible support structures for two artworks

In the A27 Houten - Hooipolder project, in the southern section, between Everdingen and Hooipolder, not only 40 kilometers of highway will be improved, but also more than 50 engineering structures will be addressed, widened or even completely replaced. Two new underpasses will be created around the Hooipolder interchange. Partly because of the specific shape of the deck, construction consortium ALSÉÉN used Matemco's advanced Kwik scaffolding system. And thanks to the high permissible upright loads of the 75 kN gaffer system, less support material was also needed and thus less labor.

Ballast Nedam, which together with Fluor Infrastructure forms construction consortium ALSÉÉN, is familiar with Matemco's systems. "We were asked to engineer and supply the support structure of both decks," says Tom Diepgrond, technical consultant at Matemco. "Especially with the underpass in the A27, the challenge was in the 'buckled' deck. We had to follow that shape with our support. Our Kwik scaffolding system lends itself perfectly to this kind of challenging shape, because of the flexible girder and post lengths as well as the high permissible post loads. This makes us very flexible in making the design, which, incidentally, we always engineer and work out in 3D."

75 kN fork system

For the underpass in the A27, Matemco supplied a total of 1,000 m2 of support material of the Kwiksteiger 75 kN gaff system type. "We positioned the uprights in such a way that we could follow the kink line well," explains Diepgrond. "One of our regular labor partners, Madema Steigerwerken, handled the assembly up to the horizontal formwork. Then the construction crew placed all the remaining formwork, the braiders went on it and concrete was poured. After curing, everything was dismantled again and some of our support material was reused and redeployed for the deck of the underpass in the Oosterhoutseweg which is now under construction and will be slid in later this year. For this, a total of 275 m2 of support will be used for a deck with an equal thickness of 700 mm."

The Mercury scaffold system is widely used in civil concrete construction. It is suitable for heavier loads and, thanks to the unique tilt plates and footplates, slopes and corners, both in the deck and at ground level, are no problem. The support system is also compatible with the Kwiksteiger scaffolding system of the same name, so that a safe workplace at height can be created if necessary within the structure. "The A27 project will take a few more years, so we hope to participate again at the next phase," Diepgrond concludes.