No_12_December_1968 — Page 33

BRITAMI

Giant floating canopy for UK at Expo '70

THE British pavilion at the Japan World Exposition, Osaka, 1970 will be suspended from four giant twin steel masts so that the whole building becomes a giant canopy floating over an open-air concourse.

Four separate exhibition halls in- terconnected by bridges will hang from the masts which rise to some 110 ft. The pairs of masts are connected at the point of suspension by rigid steel beams forming tall and narrow portals.

Main element of the horizontal structure is the roof deck, 7 ft. in depth, formed by steel lattice girders on a diagonal grid on plan. The girders are supported by their inner ends by the masts through lattice girders, and at their outer ends by steel cables. At each suspension point at the mast three cables converge; thus the roof deck is suspended on each side at 12 points at regular intervals.

The diagrid arrangements of the roof trusses result in a structure suf- ficiently rigid in the horizontal plane to resist the loads due to seismic and wind forces, transmitting them to the the masts. In view of the suspension of the whole structure, wind tunnel tests on a model of the pavilion have been carried out at the National Phy- sical Laboratory, Teddington, UK, to determine realistically the effect of wind forces.

POWELL & MOYA

TAKAKI & DODD

CHARLES WEISS & PARTNERS

C.B. BALL & PARTNERS

MINISTRY OF PUBLIC BUILDING & & WORKS

THE SHIMIZU CONSTRUCTION CO. LIMITED

H.O. BRYANT

ings are suspended from the roof deck by braced steel frames transmitting the lateral forces to the roof deck, and simple steel hangers in the centre halv- ing the effective spans of the floor beams. The floor deck is therefore suspended above ground level at heights varying between 7 ft, and 19 ft.

Vertical cantilevers

―

The masts of box section formed by welding together four universal beam profiles are large columns transmitting the whole weight of the buildings and the superimposed loads to a reinforced concrete raft, 253 ft. long, 40 ft. wide and 4 ft. thick. The raft is supported on 40 piles, 5 ft. in diameter, and carried into the dense sand at about 33 ft. to 50 ft. from the surface.

The masts are also designed as verti- cal cantilevers resisting the horizontal loads due to seismic and wind forces, The floors of the exhibition build- unbalanced loads arising from any

architects

associate architects

consulting engineers

quantity surveyors mechanical and engineering services

contractor

project manager

asymmetry of the two halves of the structure about the longitudinal axis of the building, or partial superimposed loads acting on one half of the build- ing only.

The steel framed exhibition halls will be clad in purpose designed steel- faced panels. Single-storey auxiliary buildings at ground level (administra- tive block, public lavatories and shop, etc.) will have a light steel framed structure carried on a light raft of rein- forced concrete. Some 980 tons of steel will be used in the pavilion structure.

Access to the exhibition will be by a stairway and gently sloping ramp. Beneath the exhibition halls a con- course, featuring a water garden and sitting space for visitors, will provide a transition between the outside ap- proaches and the inside of the pavilion. The canopy will give complete protec- tion from the weather for visitors en- tering and leaving the pavilion.

Far East BUILDER, December 1968

31