Post-tensioned
beams in fair stand
****
olivetti
AN award for the most original and contemporary stand design at the 26th exhibition of the Chinese Manufactur- ers' Association held recently in Hong Kong was made to Olivetti (HK) Ltd.
Their stand resembled a large sculp- ture of two giant-sized cubes standing on their edges. Entry and exit was made through the under-plane of each cube. The outside was painted in bright colours while inside the firm's machines were displayed on the walls in chequer board fashion with mirrors.
The award was made for originality
of design, but the stand was also struc- turally unusual, being the first demon- stration in Hong Kong of the use of precast post-tensioned concrete beams. Two such beams, each composed of three T-shaped precast units butted together and post-tensioned on site, were mounted on two reinforced con- crete piers, sunk 4 ft. into the site. The beams carried the entry and exit stairs to the stand and formed a base for the stand framework.
This framework was constructed from lightweight slotted angle steel
components and was clad in plywood panels.
The T-shaped units, measuring 6 ft. x 26 in. x 24 in. deep, were cast in a contractor's yard at Junk Bay. On the exhibition site they were lined up on timber runners, threaded with seven steel wires through a central duct, an- chored at one end by a sandwich an- chor plate and post-tensioned, using a Swiss BBRV jacking system.
Andrew Jean was the structural engineer for the stand, which was de- signed by Tao Ho.
▲ Precast beam being aligned
for post-tensioning
Beams being lifted by lorry ▷ crane and mounted on pier
Far East BUILDER, February 1969
Sandwiched anchor plate for post-tensioning
Post-tensioning jack
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