One of the most popular attractions in the Dome is the Rest Zone - an oasis of calm and tranquillity. Curved walls, floor and ceiling constantly change colour while a soothing soundtrack helps to create a relaxing environment. Visitors can 'chill out', standing, sitting, or even lying down in the Zone's smooth interior. This organic womb-like space has been created inside a glass fibre reinforced composite (GRP) shell strengthened by timber ribs. From the outside it looks like a rainbow-painted doughnut squashed against the floor.
One of the Dome's access bridges runs straight through the hole in the middle. It was the location of this bridge, linking a core building to the central first floor level promenade, that dictated the Zone's form. After considering a structure that either went over the bridge or under it, designer Richard Rogers Partnership and structural engineer Buro Happold decided to do both, wrapping the Zone around the bridge. Design was constrained by the Blackwall Tunnel, which runs right under the Zone.
There are no piles in the area of the tunnel, so the Rest structure had to sit on an existing ground bearing slab designed to take a load of 20kN/m2.
Buro Happold worked with Bath University to develop a mathematical model that described the shape the design team was looking for. It could be stretched and squashed by tweaking the equations until the final sculptural form was agreed.
'We used a digital model to give us the geometry of the shell - this formed the basis for analysis and construction of all elements,' says Buro Happold project engineer Mike Taverner. 'It allowed designers and fabricators to work to the same geometry.'
Laminated plywood box beam ribs measuring 600mm by 150mm provide the primary structural elements, but they work compositely with the 15mm thick GRP shell.
Plans to build the structure insitu were ditched by main contractor MICE, which employed boat builder Blondecell Marine to construct it in a Southampton boatyard. Working from the original mathmatical model a wooden framework was laser cut to shape and a plug, or male mould, produced in which to lay the GRP shell. The same model was then used to cut plywood ribs which were laminated onto the outside of the completed GRP shell.
Construction joints were moulded into the structure allowing it to be dismantled for delivery. Sections were lifted into position and laminated together by specialist stage company Star Hire.
Structural engineer: Buro Happold
Architect: Richard Rogers Partnership
Main contractor: MICE
Specialist fabrication: Blondecell Marine