8 April 2003
Sage Gateshead – intricate roof design on the Tyne
Angus Palmer, BA, CEng, MIStructE, Group Manager at Buro Happold, describes the complex three-dimensional primary roof structure of the Tyne’s newest development
The roof presently under construction on the south bank of the Tyne is designed to entirely cover the two main performance halls and a third hall rehearsal space that form Sage Gateshead, a new music centre located on the south bank of the River Tyne in Gateshead. This development will provide a new public space overlooking the Tyne and forms an apex to the rejuvenation works at Gateshead, following the Stirling Prize-winning Wilkinson Eyre Gateshead Millennium Bridge and the recently opened Baltic Centre for Contemporary Art.
The roof structure consists of four primary arches located in the slots between the main halls. The arches span about 80m between the front esplanade wall and buttresses at the rear of the site, and are profiled to a spiral form using beam segments of successively increasing radii. UB sections of about 800mm depth are used, with three internal props being used to help minimise their size.
Spanning between these primary arches are secondary arch members which are also profiled to varying radii segments along their length with each secondary arch being identical. By overlaying these members radially on the primary arches a complex three-dimensional shape is produced that consists of interlocking toroid forms. Further stiffening is then added by tertiary strut and tie members to provide shell action to the roof.
Integrated within the roof are fully glazed east and west façade walls, and large glazed apertures looking over the river to Newcastle adjacent to the main hall buildings. The remainder of the roof has a rain screen of interlocking stainless steel panels with a weather-tight membrane below.
The complex roof form was found using a process of parametric modelling whereby geometric associations were defined between member segments. This enabled the designers to rapidly explore different configurations for the primary and secondary arch profiles enabling them to assess the resulting three-dimensional form for both architectural and structural merit.
This modelling process ensured that the resulting primary and secondary members were all defined as simple two-dimensional radii segments, greatly simplifying their fabrication and offering a degree of standardisation of components and façade elements.
The hierarchy of primary and secondary members also aids the installation, whereby ladder sections of secondary arches can be lifted into place on the primary arches without the need for extensive temporary works. This not only speeds up the installation and offers cost benefits, but also allows unhindered work to take place in the building below. Further, the sequencing of the installation of the tertiary tie members has been optimised to permit similar sized bars to be used throughout, offering saving in steel weight and permitting some standardisation of detailing.
Background information for Editors:
Client: Gateshead Council
Architect: Foster and Partners
Structural engineers for the roof structure: Buro Happold
Engineer for the base buildings: Connell Mott MacDonald
Main contractor: John Laing
Specialist roof contractor: Waagner Biro
