Concrete Price for circular viaduct

DRONTEN – The construction of the first circular viaduct by Van Hattum and Blankevoort, Rijkswaterstaat and Consolis Spanbeton.

The circular viaduct in Dronten was awarded the Concrete Prize in the category ‘Circular’ on 14 November. The circular viaduct was developed by contractor van Hattum and Blankevoort, prefab builder Consolis Spanbeton and Rijkswaterstaat. The first application of this was built on the construction site of the Reevesluis near Kampen where it was tested by the work traffic from December 2018 to September 2019. The viaduct is circular because it is designed for reuse and can therefore be dismantled undamaged. For example, there is no waste, no new raw materials are needed and raw materials are reused in the highest quality way. The viaduct is made up of loose concrete elements, which have been assembled into beams for the specific application. The length of the beams is therefore variable: the more elements, the longer the beam. The elements are designed in such a way that they interlock with lugs – like LEGO blocks – and are held together with prestressing cables. The beams are placed next to each other and joined together by cross-tensioning bars into a load-bearing bridge deck. The prestressing cables and rods are used as ‘prestressing without attachment’ and are therefore also reusable. In addition, the joints are designed in such a way that they can be released again. The viaduct consists of forty concrete elements of 1.5 meters width and 2.5 meters in length. With this, a viaduct of 20 meters in length and a width of 7.5 meters has been built. By working with elements, other viaducts can also be built with it in the future, which are, for example, wider or have a longer span. In that case, the load for the elements that has already been taken into account in the design is different. The elements are designed for a lifespan of 200 years. In each beam, three prestressing cables provide the required prestressing force. These cables can be stretched and relaxed several times without damage making them reusable. Thanks to the protective casing, they are suitable for a long service life. The elements are equipped with ‘shearkeys’ or shear cams (male-female connections) that also ensure that the elements are positioned correctly. Monitoring of the first application is used to learn how the viaduct behaves in practice when the heavy construction traffic passes the bridge. Measuring sensors at the bottom of the bridge deck can detect movements of up to 0.1 mm. The voltage is also measured in the prestressing cables. The circular viaduct is an initiative of Van Hattum and Blankevoort, resulting from their ambition to be the most sustainable civil builder in the Netherlands by 2025. They were looking for (2016) partners themselves, such as Consolis Spanbeton and Rijkswaterstaat, to design and build a circular viaduct in co-creation (2017) (2018). Consolis focuses on the development and application of innovative and sustainable precast concrete building systems. After testing the circular viaduct (2019), it will be rebuilt elsewhere for its second life cycle. The acquired knowledge and skills are shared openly to inspire and motivate others to design and build circularly. ‘One of the first times that circular design has taken place,’ the jury of the Betonprijs judged. ‘An innovative concept, a forerunner.’

Existing Building: Renovation/restoration of the Maastunnel in Rotterdam Civil Construction: Albert Cuyp parking garage, Amsterdam Groundbreaking: Regiokantoor Natuurmonumenten, Zierikzee Utiliteitsbouw: Earth Simulation Laboratory, Utrecht Housing: Belvedère, Hilversum Future Prize (new this year): Museum Naturalis, Leiden

The concrete prize has been awarded every two years since 1979 to leading projects in the concrete construction sector. This year the award ceremony took place during the 62nd edition of the Concrete Day in the Van Nelle Factory. The Betondag had a future-oriented title, namely Panorama Beton. For that reason, in addition to the six categories, a Future Prize was also awarded this year. The jury evaluated 65 entries, resulting in 17 nominated projects.

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