The Bristol Alliance

Cabot Circus - Bristol

Architect: Chapman Taylor with Nayan Kulkarni
Structural Engineer: SKM
Principal Contractor: Sir Robert MacAlpine

Cabot Circus, Bristol

The design of the Cabot Circus retail centre dramatic glazed roof was a collaborative process between artist Nayan Kilkarni, architects Chapman Taylor and engineers SKM and the resulting 5,800m2 grid shell structure provides a roof covering that radiates from the central retail area out into the adjoining streets. Linking five individual buildings the central main roof structure was the first major structure of its kind in the UK. SH Structures were responsible for the supply, manufacture and installation of the various roof structures. When tackling schemes such as this our close working relationship with the clients’ professional team and the main contractor plays a major part in a projects success.

With many factors to consider from the roofs structural integrity to how it would be fabricated and installed team work is essential. One of our first exercises was to build a full scale mock-up of a typical section of the roof. Whilst not being an approach suitable to every project, building such a mock-up can bring significant benefits to a scheme. After working with SKM to rationalise the structure we delivered the roof in a series of ladder frames which were installed on a load bearing scaffold before being welded together into one seamless structure. Rigorous 3d dimensional control had to be employed to ensure each node was in its correct location so that when the structure was eventually self-supporting the resulting geometry and form would correlate with the calculated predicted design.

The finished roof is stunning and a credit to all those involved and the scheme was chosen as a winner of a Structural Steel design Award in 2009. In addition to the roof, SH Structures also supplied and installed the schemes glazed bridge which provides access to the development from the nearby multi-storey car park. (Details of the bridge can be found with the bridges section of our projects)