A CURVED DOUBLE-SKIN SPACE FRAME STRUCTURE
The library is set in a courtyard. Its five floors are elliptical in plan and rise freely within a 64 x 55m domelike enclosure, 19m high. The floors curve sinuously at the peripheral edges.
The dome-like enclosure is formed of a space-frame structure lined on the inside with white silicone-coated glass fibre fabric panels and translucent ETFE panels and on the outside with double-glazed panels and insulated metal panels. The space-frame structure is made up of painted CHS members. The fabricator, Mero, used a CAD/CAM system to optimise their diameters; they vary from 75mm to150mm diameter to suit their position in the frame.
The CHSs have tapered ends and are connected to spherical steel nodes, which also vary in size and shape.
Each glass fibre fabric panel is clamped to an aluminium frame and the edges pre-stressed with Velcro tape.
The frame is bolted to a 12mm base plate and its position in relation to the CHS structure is adjusted with a threaded bolt and clamp plate. A slightly different connection is used where the frames are connected to a spherical steel node.
The external skin consists of panels of insulated polyester powder-coated aluminium and toughened and laminated double-glazed units set in 90mm SHS frames and fi xed with neoprene clamping profiles.