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Sydney Opera House

Medium Use: Concrete frame & precast concrete ribbed roof

Construction Date started: March 1, 1959

Opening Date: October 20, 1973

Architect : Jørn Utzon

Structural engineer: Ove Arup & Partners

Main contractor: Civil & Civic (level 1), M.R. Hornibrook (level 2 and 3 and interior)

Description:

The facility features a modern expressionist design, with a series of large precast concrete "shells", each composed of sections of a sphere of 75.2 metres (246 ft 8.6 in) radius, forming the roofs of the structure, set on a monumental podium. The building covers 1.8 hectares (4.4 acres) of land and is 183 m (600 ft) long and 120 m (394 ft) wide at its widest point. It is supported on 588 concrete piers sunk as much as 25 m (82 ft) below sea level.

Although the roof structures are commonly referred to as "shells" (as in this article), they are precast concrete panels supported by precast concrete ribs, not shells in a strictly structural sense. Though the shells appear uniformly white from a distance, they actually feature a subtle chevron pattern composed of 1,056,006 tiles in two colours: glossy white and matte cream. The tiles were manufactured by the Swedish company Höganäs AB which generally produced stoneware tiles for the paper-mill industry.

Apart from the tile of the shells and the glass curtain walls of the foyer spaces, the building's exterior is largely clad with aggregate panels composed of pink granite quarried at Tarana. Significant interior surface treatments also include off-form concrete, Australian white birch plywood supplied from Wauchope in northern New South Wales, and brush box glulam.

Of the two larger spaces, the Concert Hall is in the western group of shells, the Joan Sutherland Theatre in the eastern group. The scale of the shells was chosen to reflect the internal height requirements, with low entrance spaces, rising over the seating areas up to the high stage towers. The smaller venues (the Drama Theatre,...