Location: Copenhagen, Denmark
The ArborSystem is becoming the main choice of suspended pavement system for tree pits in various urban development projects across Europe. Andreas Brunnum, from LK Group, was the project manager for the Havnegade, Kobenhavn and the Søborg, Hovedgade projects.
The Havnegade project is a one kilometer stretch of urban redevelopment in the harbour area of Copenhagen, where nine trees were planted. Under the Søborg/Hovedgade project, the Soborg main street was upgraded to become a beautiful greener commercial street. Around 30 trees were planted in the median strip. The concrete in the media strip was a hindrance for planting trees and getting optimum growth conditions so the old tram rails were removed as well as the thick layer of asphalt and concrete. A total of four sites were renovated around the area. Brunnum said that using the StrataCell allowed the trees to grow better. “The pavement will make room for the roots to grow and at the same time you are able to drive the traffic very close to the trees without damaging the roots because of the StrataCells.” The structural soil cells come in modular units, which can then be assembled to form a skeletal matrix that supports pavement and traffic loads. The StrataCell system features almost five times more available growing media compared to the traditional structural soil method, therefore facilitating healthy root growth.
As recently proven in a laboratory test in Edmonton, Alberta, the StrataCell system can sustain the weight of an ASV PT-50 multi-terrain loader. An assembled StrataCell matrix has been FEA tested to 550kPa vertical load. The modules feature extremely high compressive strength and the unique, globally patented, interlocking feature provides correct dispersion of wheel loads throughout the matrix. Although structural soil matrix is a cheaper and more common alternative in Scandinavia, there is quite a big risk involved when a contractor installs it incorrectly. With ArborSystem, our consultants go to site and install the first tree pit with the contractor, to answer any questions they may have and give them tips on how to install more efficiently. The StrataCell’s interconnected skeletal matrix provides over 94% void space for filling with soil or storing stormwater. Aside from having a very high strength capacity, the modules are also manufactured from 100% recycled polymer. And since there are no steel components, the modules are corrosion-free.“People use it because ArborSystem optimizes the space that’s available so they don’t have to move utilities and services. Structural soil only has about 20% rootable space, while GreenBlue soil cells have over 90% – so you get three times as much rootable soil volume.”Although the rock soil matrix is still the most commonly used system in Scandinavia, StrataCells is becoming more and more popular. “Mainly because it’s a safe way of planning and installation. Engineers and architects prefer this. They can now start planning tree pits where they can, also especially because space is a problem in European cities,” Wyatt says.
For more information on this project, contact our Denmark partner, Milford.