A good place to unwind

Steel imitates life in the spiral ribs fabricated from plate steel to form the structure of the Spiral Café in Birmingham’s Bullring Centre.

The shape of the spirals is based on the Fibonacci series, which occurs in nature in the proportions of plants and shells, and is used as a proportioning system in architecture.

The striking design was by architect Marks Barfield, best known for the London Eye, and structural engineer Price and Myers 3D Engineering.

The structure id formed by eight similar spiral ribs setout radially in plan and tilted relative to each other form the structure. The first three are supported at each end. The other five, which cantilever, are designed to act with circular hollow section bracing,which makes the shell of the building work as a truss.

The structure was modelled using the SolidWorks 3D CAD package, and laser cut from steel plate. It was designed as seven modules bolting together along the centre-line of each rib. “We designed it to be as easy as possible to make and to keep accurate,” says Price and Myers 3D Engineering partner Tim Lucas. The whole building was assembled in the workshop, then dismantled into 14 sections for reassembly on site.

The steel ribs are clad in copper externally and by a stainless steel capping piece internally.