Vision Australia's Carols by Candelight presented by AAMI is held on Christmas Eve at the iconic Sidney Myer Music Bowl venue in the Kings Domain in Melbourne!
Carols by Candlelight was the concept of Norman Banks MBE with the first event being held in 1938.
The current venue for Carols by Candlelight - since its completion in 1959 - is a pioneering, world class example of tensile architecture using stressed cables in a double curvature form to resist environmental loads (wind) and to act as an effective sound shell for music.
This is a unique tensile cablenet structure was designed by Barry Patten of the Architectural firm Yuncken Freeman Brothers, Griffiths and Simpson. Engineering was done by Irwin Johnstone.
The venue is named after Sidney Myer, a Russian immigrant who arrived in Melbourne in 1899 and establish Myers. He also started an annual Music for the People with the Melbourne Symphony Orchestra in 1929. He was an important philanthropist and wanted a more permanent home for these annual performances. The setting in the Botanical Gardens would be used for the "Bowl" which was opened in 1959 some 25 years after his death.
For the LSAA, the structure can be regarded as a huge leap forward in freeform tensile architecture. It remains perhaps the largest auditorium for concerts. It was at least a decade ahead of the cablenet structures of the better known Frei Otto who developed freeform cable structures for the 1967 Expo in Montreal and later the best known roof for the main stadium for the 1972 Munich Olympics.
The shape of the surface is defined by the orthogonal grid of opposing pretensioned cables that form a double curvature, or "saddle shape".
The main environmental loading in Australia is from wind. There would have been no guidelines as to the wind pressures exerted on this new shape but clearly one would design for both a downward pressure as well as an uplift. The cables in one direction would resist the downward pressures whilst the opposing cables would resist the uplift pressures. Both sets of cables were pre-stressed so that under any wind loads they would remain taut.
These pre-stress forces are the other main loading to design for.
Computer analysis programs were not yet readily available and it would be perhaps two decades later before large displacement analysis capabilities were becoming available for more widespread use.
The structure was refurbished in about 2001. It is currently operated by the Victorian/Melbourne Arts Centre.
The main stage is about 27m wide x 19.5m deep and the canopy is just over 4000 sqm. The images above show the waterproofed plywood panels sheeted on both sides with Aluminium and clamped to the cable-net. Gathering the forces from the cablenet the edge cable comprises seven wire rope some 90mm in diameter and an overall length of 173 metres. The pivoting vertical masts are 21.3 m high.
The cables essentially at right angles to the main edge cables tend to lift the roof whilst those somewhat parallel to the open edge cable have the opposite curvature and stabilize the roof against wind uplift. The resulting surface shape is called "double curvature", "saddle shaped" or "anticlastic" and is the basis for our tensile fabric architecture designs.
Further Reading (use Back button to return):
http://www.environment.gov.au/heritage/places/national/sidney-myer-music-bowl
https://architectureau.com/articles/sidney-myer-music-bowl/
https://vhd.heritagecouncil.vic.gov.au/places/64306/download-report
