Editing Sydney Opera House (section)

===Design development and construction timeline===
====Preparation of site====
The [[Fort Macquarie Tram Depot]], occupying the site at the time of these plans, was demolished in 1958 and construction began in March 1959. The Opera House was built in four stages: stage I (1957–1959) was planning out the building; stage II (1959–1963) consisted of building the upper podium; stage III (1963–1967) the construction of the outer shells, based upon the image of whales breaching the water; stage IV (1967–1973) interior design and construction.{{cn|date=February 2024}}

====Stage I: Podium====
Stage I started on 2 March 1959 with the construction firm [[Civil & Civic]], monitored by the engineers [[Arup Group Limited|Ove Arup and Partners]].<ref name=sa>[http://www.sydneyarchitecture.com/ROC/QUA01.htm Sydney Architecture] {{Webarchive|url=https://web.archive.org/web/20070927010222/http://sydneyarchitecture.com/ROC/QUA01.htm |date=27 September 2007 }}. Retrieved 1 November 2008.</ref> The government had pushed for work to begin early, fearing that funding, or public opinion, might turn against them. But Utzon had still not completed the final designs. Major structural issues still remained unresolved. By 23 January 1961, work was running 47 weeks behind,<ref name=sa/> mainly because of unexpected difficulties (inclement weather, unexpected difficulty diverting stormwater, construction beginning before proper construction drawings had been prepared, changes of original contract documents). Work on the podium was finally completed in February 1963. The forced early start led to significant later problems, not least of which was that the podium columns were not strong enough to support the roof structure, and had to be re-built.<ref name="PMurray">{{cite book
 | last = Murray
 | first = Peter
 | title = The Saga of the Sydney Opera House
 | publisher=Spon Press
 | year = 2004
 | location = London
 | isbn = 0-415-32521-8 }}</ref>

====Stage II: Roof====
<gallery mode="packed" heights="150">
File:SYDNEY OPERA HOUSE under construction and ferries including BELLUBERA and KARINGAL 1962.tif|Podium structure complete, 1962
File:SYDNEY OPERA HOUSE under construction 1965.tif|Shells structure, {{Circa|1965}}
File:SYDNEY OPERA HOUSE under construction circa 1965.tif|Roof and shell structure, {{Circa|1965}}
File:Sydney Opera House construction 1968.jpg|Tiles complete, {{Circa|1968}}
</gallery>
The [[Thin-shell structure|shells]] of the competition entry were originally of undefined geometry,<ref>Arup, Ove and Zunz, G.J.: Article in ''Structural Engineer'' Volume 47, March 1969</ref> but, early in the design process, the "shells" were perceived as a series of [[parabola]]s supported by precast concrete ribs. However, engineers [[Arup Group|Ove Arup and Partners]] were unable to find an acceptable solution to constructing them. The [[formwork]] for using ''[[in-situ]]'' concrete would have been prohibitively expensive, and, because there was no repetition in any of the roof forms, the construction of precast concrete for each individual section would possibly have been even more expensive.

[[File:AUS NSW Opera House DSC05118.jpg|thumb|right|Sydney Opera House shell ribs]]
[[File:Sydney Opera House Ceramic Tile Pattern.jpg|thumb|right|The glazed ceramic tiles of the Sydney Opera House]]
From 1957 to 1963, the design team went through at least 12 iterations of the form of the shells trying to find an economically acceptable form (including schemes with parabolas, circular ribs and [[ellipsoids]]) before a workable solution was completed.

The design work on the shells involved one of the earliest uses of computers in [[structural analysis]], to understand the complex forces to which the shells would be subjected.<ref name="PJones">Jones, Peter: ''Ove Arup: Masterbuilder of the Twentieth Century''. Yale University Press, 2006.</ref><ref name=bertony>{{cite web |url=https://www.bbc.co.uk/news/world-australia-47880938 |title=Joseph Bertony: The spy who helped mastermind the Sydney Opera House|website=BBC News |first=Ashitha |last=Nagesh |date= 13 April 2019}}</ref> The computer system was also used in the assembly of the arches. The pins in the arches were surveyed at the end of each day, and the information was entered into the computer so the next arch could be properly placed the following day.

In mid-1961, the design team found a solution to the problem: the shells all being created as sections from a sphere. This solution allows arches of varying length to be cast in a common mould, and a number of arch segments of common length to be placed adjacent to one another, to form a spherical section. With whom exactly this solution originated has been the subject of some controversy. It was originally credited to Utzon. Ove Arup's letter to Ashworth, a member of the Sydney Opera House Executive Committee, states: "Utzon came up with an idea of making all the shells of uniform curvature throughout in both directions."<ref name=autogenerated3>page 199</ref> Peter Jones, the author of Ove Arup's biography, states that "the architect and his supporters alike claimed to recall the precise [[Eureka effect|''eureka'' moment]] ...; the engineers and some of their associates, with equal conviction, recall discussion in both central London and at Ove's house."

He goes on to claim that "the existing evidence shows that Arup's canvassed several possibilities for the geometry of the shells, from parabolas to ellipsoids and spheres."<ref name="PJones" /> Yuzo Mikami, a member of the design team, presents an opposite view in his book on the project, ''Utzon's Sphere''.<ref name="sphere">{{cite web| author=Bentley, Paul| date=September 2001| title=A Matter of Integrity – A Review of Yuzo Mikami's ''Utzon's Sphere''| publisher=The Wolanski Foundation| url=http://www.twf.org.au/research/mikami.html| access-date=30 January 2007| archive-url=https://web.archive.org/web/20070102161608/http://www.twf.org.au/research/mikami.html| archive-date=2 January 2007| url-status=dead| df=dmy-all}}</ref><ref>Mikami, Yuzo: ''Utzon's Sphere'', Tokyo: Shoku Kusha. 2001.</ref> It is unlikely that the truth will ever be categorically known, but there is a clear consensus that the design team worked very well indeed for the first part of the project and that Utzon, Arup, and Ronald Jenkins (partner of Ove Arup and Partners responsible for the Opera House project) all played a very significant part in the design development.<ref name="findarticles">{{cite news|author=Hunt, Tony |date=October 2001 |title=Utzon's Sphere: Sydney Opera House—How It Was Designed and Built—Review |publisher=EMAP Architecture, Gale Group |url=http://www.findarticles.com/p/articles/mi_m3575/is_1256_210/ai_79759827 |archive-url=https://web.archive.org/web/20061219120138/http://findarticles.com/p/articles/mi_m3575/is_1256_210/ai_79759827 |url-status=dead |archive-date=19 December 2006 |access-date=30 January 2007 }}</ref>

As [[Peter Murray (architectural writer)|Peter Murray]] states in ''The Saga of the Sydney Opera House'':<ref name="PMurray" />

{{blockquote|... the two men—and their teams—enjoyed a collaboration that was remarkable in its fruitfulness and, despite many traumas, was seen by most of those involved in the project as a high point of architect/engineer collaboration.}}

The design of the roof was tested on scale models in [[wind tunnel]]s at [[University of Southampton]] and later [[National Physical Laboratory (United Kingdom)|NPL]] to establish the wind-pressure distribution around the roof shape in very high winds, which helped in the design of the roof tiles and their fixtures.<ref>{{cite web |url=http://www.powerhousemuseum.com/mob/collection/database/?irn=12041&img=7593 |title=Model of Sydney Opera House, 1960 |work=Powerhouse Museum – Collection Database |year=2014 |access-date=6 May 2014 |archive-url=https://web.archive.org/web/20140506212436/http://www.powerhousemuseum.com/mob/collection/database/?irn=12041&img=7593 |archive-date=6 May 2014 |url-status=live }}</ref><ref>{{cite web |url=http://www.npl.co.uk/content/conWebDoc/8580 |title=Building the Sydney Opera House |work=npl.co.uk |year=2014 |access-date=6 May 2014 |archive-url=https://web.archive.org/web/20140506200203/http://www.npl.co.uk/content/conWebDoc/8580 |archive-date=6 May 2014 |url-status=dead }}</ref>
[[File:Sydney Opera House At Night 2.jpg|thumb|The shells of the Opera House at night, viewed from the south]]
The immensely complex design and construction of the shells was completed by [[Bilfinger Berger|Hornibrook Group Pty Ltd]],<ref>{{cite web |url=http://www.bilfingerberger.com/C1257130005050D5/vwContentByKey/W26U3AX8814LUNADE/$FILE/bb_historie_en.html |title=Bilfinger Berger corporate history |publisher=Bilfingerberger.com |access-date=23 September 2013 |url-status=dead |archive-url=https://web.archive.org/web/20100324054618/http://www.bilfingerberger.com/C1257130005050D5/vwContentByKey/W26U3AX8814LUNADE/%24FILE/bb_historie_en.html |archive-date=24 March 2010 }}</ref> who were also responsible for construction in Stage III.<ref>{{SLQ-CC-BY|url=https://www.slq.qld.gov.au/blog/archives-reveal-more-history-hornibrook-innovation-building-sydney-opera-house|title=Archives reveal more history of Hornibrook innovation in the building of Sydney Opera House.|date=3 November 2021|author(s)=Julie Hornibrook|accessdate=1 June 2022}}</ref> Hornibrook manufactured the 2400 precast ribs and 4000 roof panels in an on-site factory and also developed the construction processes.<ref name="PMurray" /> The achievement of this solution avoided the need for expensive formwork construction by allowing the use of precast units and it also allowed the roof tiles to be prefabricated in sheets on the ground, instead of being stuck on individually at height.

The tiles themselves were manufactured by the Swedish company [[Höganäs Keramik]]. It took three years of development to produce the effect Utzon wanted in what became known as the Sydney Tile, 120mm square. It is made from clay with a small percentage of crushed stone.<ref>{{cite web| url = https://www.sydneyoperahouse.com/our-story/sydney-opera-house-history/spherical-solution.html| title = sydneyoperahouse.com}}</ref>

Ove Arup and Partners' site engineer supervised the construction of the shells, which used an innovative adjustable steel-trussed "erection arch" (developed by Hornibrook's engineer [[Joe Bertony]]) to support the different roofs before completion.<ref name=bertony/> On 6 April 1962, it was estimated that the Opera House would be completed between August 1964 and March 1965.

====Stage III: Interiors====
<gallery mode="packed" heights="160">
File:SSO at the Concert Hall in the Sydney Opera House on 20 July 2022.jpg|The Concert Hall and [[Sydney Opera House Grand Organ|organ]]
File:Concert Hall Interior.JPG|View from the stage of the Concert Hall
File:Joan Sutherland Theatre Interior.JPG|View from the stage of the Joan Sutherland Theatre
File:Studio Theatre Interior.JPG|Interior of the Studio Theatre
</gallery>
Stage III, the interiors, started with Utzon moving his entire office to Sydney in February 1963. However, there was a change of government in 1965, and the new [[Robert Askin]] government declared the project under the jurisdiction of the Ministry of Public Works. Due to the Ministry's criticism of the project's costs and time,<ref>{{Cite web|url=http://www.sydneyoperahouse.com/About/The_Architect.aspx|title=Sydney Opera House – the Architect – Sydney Opera House|website=www.sydneyoperahouse.com|access-date=10 May 2016|archive-url=https://web.archive.org/web/20160513175048/http://www.sydneyoperahouse.com/about/the_architect.aspx|archive-date=13 May 2016|url-status=dead}}</ref> along with their impression of Utzon's designs being impractical, this ultimately led to his resignation in 1966 (see below).

The cost of the project so far, even in October 1966, was still only [[Australian dollar|A$]]22.9&nbsp;million,<ref>[http://www.sydneyarchitecture.com/ROC/QUA01.htm Sydney Architecture] {{Webarchive|url=https://web.archive.org/web/20070927010222/http://sydneyarchitecture.com/ROC/QUA01.htm |date=27 September 2007 }}. Retrieved 1 December 2008.</ref> less than a quarter of the final $102&nbsp;million cost. However, the projected costs for the design were at this stage much more significant.
[[File:Sydney Opera House Concert Theatre.JPG|thumb|The Concert Hall prior to renovations in 2020]]
The second stage of construction was progressing toward completion when Utzon resigned. His position was principally taken over by [[Peter Hall (architect)|Peter Hall]], who became largely responsible for the interior design. Other persons appointed that same year to replace Utzon were E. H. Farmer as government architect, D. S. Littlemore and Lionel Todd.

Following Utzon's resignation, the acoustic advisor, Lothar Cremer, confirmed to the Sydney Opera House Executive Committee (SOHEC) that Utzon's original acoustic design allowed for only 2,000 seats in the main hall and further stated that increasing the number of seats to 3,000 as specified in the [[brief (architecture)|brief]] would be disastrous for the acoustics. According to Peter Jones, the stage designer, Martin Carr, criticised the "shape, height and width of the stage, the physical facilities for artists, the location of the dressing rooms, the widths of doors and lifts, and the location of lighting switchboards."<ref name=autogenerated4>page203</ref>

====Significant changes to Utzon's design====
[[File:Foyer of Opera Theatre, Sydney Opera House, jjron, 03.12.2010.jpg|thumb|The foyer of the Joan Sutherland Theatre, showing the internal structure and steel framing of the glass curtain walls; the final constructions were modified from Utzon's original designs]]
[[File:Sydney Opera House - interior (2).jpg|thumb|The foyer of the Concert Hall]]
* The major hall, which was originally to be a multipurpose opera/concert hall, became solely a concert hall, called the Concert Hall. The minor hall, originally for stage productions only, incorporated opera and ballet functions and was called the Opera Theatre, later renamed the Joan Sutherland Theatre. As a result, the Joan Sutherland Theatre is inadequate to stage large-scale opera and ballet. A theatre, a cinema and a library were also added. These were later changed to two live drama theatres and a smaller theatre "in the round". These now comprise the Drama Theatre, the Playhouse and the Studio respectively. These changes were primarily because of inadequacies in the original competition brief, which did not make it adequately clear how the Opera House was to be used. The layout of the interiors was changed, and the stage machinery, already designed and fitted inside the major hall, was pulled out and largely thrown away, as detailed in the 1968 BBC TV documentary ''Autopsy on a Dream'', which "chronicles the full spectrum of controversy surrounding the construction of the Sydney Opera House".<ref>Anderson, Doug: [https://www.theguardian.com/tv-and-radio/2013/oct/21/autopsy-on-a-dream-unflattering-national-psyche Review of rediscovered Sydney Opera House film ''Autopsy on a Dream''] {{Webarchive|url=https://web.archive.org/web/20160305064511/http://www.theguardian.com/tv-and-radio/2013/oct/21/autopsy-on-a-dream-unflattering-national-psyche |date=5 March 2016 }} at ''[[The Guardian]]'', 21 October 2013</ref>
* Externally, the cladding to the podium and the paving (the podium was originally not to be clad down to the water, but to be left open).
* The construction of the glass walls: Utzon was planning to use a system of prefabricated plywood [[mullion]]s, but a different system was designed to deal with the glass.
* Utzon's plywood corridor designs, and his acoustic and seating designs for the interior of both major halls, were scrapped completely. His design for the Concert Hall was rejected as it only seated 2000, which was considered insufficient.<ref name="PJones"/> Utzon employed the acoustic consultant Lothar Cremer, and his designs for the major halls were later modelled and found to be very good. The subsequent Todd, Hall and Littlemore versions of both major halls have some problems with acoustics, particularly for the performing musicians. The orchestra pit in the Joan Sutherland Theatre is cramped and dangerous to musicians' hearing.<ref>{{cite news |author=Morgan, Joyce |date=November 2006 |title=The phantoms that threaten the Opera House |url=http://www.smh.com.au/news/national/the-phantoms-that-threaten-the-opera-house/2006/11/10/1162661901377.html |access-date=13 March 2007 |work=[[The Sydney Morning Herald]] |archive-url=https://web.archive.org/web/20071016055723/http://www.smh.com.au/news/national/the-phantoms-that-threaten-the-opera-house/2006/11/10/1162661901377.html |archive-date=16 October 2007 |url-status=live }}</ref> The Concert Hall has a very high roof, leading to a lack of early reflections onstage—[[perspex]] rings (the "acoustic clouds") hanging over the stage were added shortly before opening in an (unsuccessful) attempt to address this problem.

====Completion and cost====
The Opera House was formally completed in 1973, having cost [[Australian dollar|$]]102&nbsp;million.<ref>New South Wales Government, Department of Commerce, [http://www.records.nsw.gov.au/state-archives/guides-and-finding-aids/archives-in-brief/archives-in-brief-30] {{Webarchive|url=https://web.archive.org/web/20141126044007/http://www.records.nsw.gov.au/state-archives/guides-and-finding-aids/archives-in-brief/archives-in-brief-30|date=26 November 2014}} Accessed 3 December 2014</ref> H.R. "Sam" Hoare, the Hornibrook director in charge of the project, provided the following approximations in 1973:
Stage I: podium Civil & Civic Pty Ltd approximately $5.5m.
Stage II: roof shells M.R. Hornibrook (NSW) Pty Ltd approximately $12.5m.
Stage III: completion The Hornibrook Group $56.5m.
Separate contracts: stage equipment, stage lighting and organ $9.0m. Fees and other costs: $16.5m.

The original cost and scheduling estimates in 1957 projected a cost of [[Australian pound|£]]3,500,000 ($7&nbsp;million) and completion date of 26 January 1963 ([[Australia Day]]).<ref name="PJones"/> In reality, the project was completed ten years late and 1,357% [[over budget]] in real terms.

==== Strike and Workers' Control ====
In 1972, a construction worker was fired, leading the [[Builders Labourers Federation|BLF]]-affiliated workers to demand his rehiring and a 25% wage increase. In response to this, all the workers were fired, and in revenge the workers broke into the construction site with a crowbar and brought their own toolboxes. [[Workers' control]] was applied to the site for five weeks as the construction workers worked 35 hours a week with improved morale, more efficient organization and fewer people skipping work. The workers agreed to end their work-in when management agreed to give them a 25% wage increase, the right to elect their foremen, four weeks annual leave and a large payment for their troubles.<ref>{{Cite book|title=New Forms of Worker Organization: The Syndicalist and Autonomist Restoration of Class Struggle Unionism – Chapter 10: Doing without the boss: Workers' Control Experiments in Australia in the 1970s|last=Ness|first=Immanuel|year=2014}}</ref><ref>{{Cite web |date=23 March 2022 |title=The 1972 Sydney Opera House Work-In |url=https://commonslibrary.org/the-1972-sydney-opera-house/ |access-date=18 May 2022 |website=The Commons |language=en-AU}}</ref>