Your browser is no longer supported

For the best possible experience using our website we recommend you upgrade to a newer version or another browser.

Your browser appears to have cookies disabled. For the best experience of this website, please enable cookies in your browser

We'll assume we have your consent to use cookies, for example so you won't need to log in each time you visit our site.
Learn more

Shared Ground Zone


Towering more than 20m above the floor of the Dome, the cardboard columns of the Shared Ground Zone serve as a graphic illustration of the underlying theme of sustainability and recyclability. Columns and cladding alike are almost entirely constructed of recycled paper, forming what is claimed to be the largest structure of its type in the world to date. Even the steel and plywood mezzanine floor at the elliptical heart of the Zone's two-storey spiral is designed to be easy to recycle, says structural designer Buro Happold project engineer Helen Gribbon.

'In particular the floor is made up of plywood over steel Holorib panels without any concrete in them. But it was the 100, 500mm diameter columns that were the real challenge,' she says.

Tests at the University of Bath had shown cardboard failed at a compressive stress of less than 9N/mm2. Unfortunately, creep was high, and there was only partial recovery after loading was removed. 'So we decided a safe working stress would be 0.8N/mm2, less than 10% of failure loading,' Gribbon reports.

Cardboard specialist Sonocco used high quality recycled paper bonded with PVA adhesive to make up columns with 14.5mm thick walls. Aluminium foil was bonded to the outside of the columns to protect against moisture ingress. Cardboard collected after an appeal on BBC TV's Blue Peter programme went into the horizontal bracing tubes and into the cladding, basically two sheets of card glued onto a central cardboard honeycomb.

The columns range in height from 11.5m around the core to 22m at the end of the dramatic wing wall, and are set up at 2m centres. Despite being protected by the Dome, the Zone still had to be designed to resist significant air movements.

The tops of the central columns are braced with a steel truss and 'wind' loads are taken by crossbracing between four pairs of columns with cables joined at a central steel flitch plate.

More cables tie the 22m tall raking end column back to the roof level truss. A clear intumescent coating applied to all cardboard elements provides the necessary Class O spread of flame performance. Where needed, the cladding panels hide steel sheets or fibre fill, for enhanced fire resistance or acoustic performance respectively.

Zone facts

Sponsor: Camelot

Architect: Gumuchdjian + Spence with Shigeru Ban

Structural and M&E engineer: Buro Happold

Main contractor: Mivan

Have your say

You must sign in to make a comment

Please remember that the submission of any material is governed by our Terms and Conditions and by submitting material you confirm your agreement to these Terms and Conditions. Please note comments made online may also be published in the print edition of New Civil Engineer. Links may be included in your comments but HTML is not permitted.