Evening Meeting: Geometry and structure - the benefit of the third dimension

Traditional structures are mainly two-dimensional diagrams - readily conceived and simple to sketch. The third dimension is usually an added complication demanding that structures remain stable in this direction as well.
But if we embrace this third dimension (usually one of the lateral dimensions) as an opportunity for greater structural resistance, then we might find many other possible solutions - curvature can become our greatest ally.

Three dimensional structures come in many guises, including:
• two-dimensional form with a 3D twist
• pure, form found tension structures
• singly- and doubly-curved compression shells
• pre-stressed tension elements combined with struts
• lyrical forms that nevertheless are structurally competent
• structures that occupy three-dimensional space

This paper will touch lightly on all these types of structure using real examples and providing the author’s personal views of some of the issues involved. Examples include:
• Brickpit Ring with Durbach Block
• Aurora Place Canopy, with Renzo Piano
• Royal Agricultural Showground Exhibition Halls with Ancher Mortlock and Woolley
• Brisbane Convention and Exhibition Centre with Philip Cox
• proposed stadium for Durban with Philip Cox and ArupSport
• City of Manchester Stadium, Arup Associates
• Khalifa Stadium with Philip Cox and PTW Architects
• Marina Bay Bridge with Philip Cox and Architects 61
• Water Cube, with PTW Architects and CSCEC.

Tristram Carfrae, MA, RDI, FTSE, MIEAust, MIStructE
Principal Director, Arup
Arup Fellow