A structure of steel trusses and polyester fabric
The single-storey 12 x 36m structure has been designed to be used for a year before relocation to a permanent site. It comprises a series of 13 demountable steel trusses covered with a white pvc-coated polyester fabric panels; they span 14m over twelve 12 x 3m modular building units which house the centre.
A typical truss is made up of three sections; two curved sections which form the sides and a straight section across the top. Each truss is formed of top and bottom chords of 127 x 64mm steel channels with 50 x 25mm box sections as the webs.
The trusses are braced by 60mm diameter purlins which run the length of the structure and are bolted to the inner chords. The end bays are fitted with tubular K-braces to resist fabric tension; other bays are stabilised with steel cross-braces and sway-braces.
The pvc-coated polyester fabric panels are sleeved with cables. At each truss position a curved 127 x 64mm rsc, fixed to the web members, follows the profile of the roof; the sleeved edges of the fabric panels are fixed with tensioning bolts to the flanges of the channel.
The long side of one modular unit is fully glazed and forms the entrance wall. It is a single sheet of 15mm toughened and heat-soaked glass with glass double doors set into it. The glass is set in an aluminium frame. The polyester fabric has been extended over the glass wall to form a canopy, rather like a pram hood. It is fixed to a single curved steel tube which gives a smooth profile to the front edge of the structure.
Each truss terminates at its base in a purpose-designed foot which is bolted with resin anchors into reinforced concrete pad foundations.