Over the past few months KWS Infra Leek has been carrying out major maintenance works on the western and eastern ring roads of the northern Dutch city of Groningen. The project involved the first relatively large-scale application of KonwéCity 80, a noise-reducing asphalt mixture developed by KWS, representing a first for the client, the province of Groningen. Work was completed last weekend.
KonwéCity 80 is a further development of KonwéCity 50, a noise-reducing asphalt mixture for inner-city areas that KWS has been using since 2013. KonwéCity 80 has been specifically developed for roads with speeds of up to 80 km/h. By reducing noise and lowering rolling resistance the KonwéCity mixtures boost sustainability in the surrounding area. Lower rolling resistance means that vehicles using the road consume less fuel, thus reducing carbon emissions. Noise and emission reduction is strongly consistent with the province’s sustainability policy.
AC 16 bind with recycled asphalt
KonwéCity 80 is an alternative to SMA 8G+ but is in fact a stronger product: better embedding of the aggregate in the mixture delays ravelling and thus extends the lifespan of the road surface.
For the interlayer we used AC 16 bind with 75% recycled asphalt, higher than the average used in road construction. In addition we replaced the usual thermo marking with bio-based marking: instead of chemical resin we used a natural resin for the markings over a 28-kilometre stretch of road.
8500 tonnes of asphalt was applied
In eight stages a total of around six kilometres of ring road was given a new layer of asphalt. Efforts peaked on one day during the May holiday period when a total of around 70 colleagues from KWS Infra Leek and partners were working on the road with equipment that included four milling cutters, five suction road-cleaning machines, three asphalt equipment sets, a shuttle buggy, various cranes and 24 trailers. A total of around 8,500 tonnes of asphalt was applied, including 4,000 tonnes of KonwéCity 80.
Most of the work on the western ring road was carried out during the May holiday period in order to minimise disruption and keep traffic flowing as much as possible. Work started on Sunday 28 April with the last road closure taking place last weekend to allow completion of the work.
Partners on this project were:
- Milling work: VolkerWessels subsidiary NFM
- Transport: Van der Wiel (Drachten)
- Road markings: NWM (Oosterwolde)
- Road cleaning: Veegservice Noord-Nederland
- Transport: Mechielsen Oldehove