Editing Reinforced concrete (section)

== History ==
The early development of the reinforced concrete was going on in parallel in England and France, in the middle of the 19th century.{{sfn|Eisenbach|2017|p=50}}

[[File:Saint-Denis - Maison François Coignet -1.JPG|thumb|François Coignet House at 72 rue Charles-Michels, Saint Denis]]
French builder {{ill|François Coignet |fr |François Coignet}} was the first one to use iron-reinforced concrete as a building technique.<ref>{{cite encyclopedia |url=https://www.britannica.com/technology/building-construction/Early-steel-frame-high-rises#ref105155 |title=Building construction: The invention of reinforced concrete |url-access=subscription |encyclopedia=Encyclopedia Britannica |access-date=2018-09-27 |archive-date=2018-09-28 |archive-url=https://web.archive.org/web/20180928005354/https://www.britannica.com/technology/building-construction/Early-steel-frame-high-rises#ref105155 |url-status=live }}</ref> In 1853-55, Coignet built for himself the first iron reinforced concrete structure, a four-story house at 72 [[rue Charles Michels]] in the suburbs of [[Paris]] known as the {{ill|François Coignet House|fr|Maison de François Coignet}}.<ref>{{Cite web |title= The oldest concrete structures that have lasted: 72 rue Charles Michels, St. Denis, France |publisher= Mevaline Fôrmas e Acessórios LTDA, Brasil |url=https://meva.net/pt-br/oldest-concrete-structures/ |access-date= 25 March 2025}}</ref> Coignet's descriptions of reinforcing concrete suggests that he did not do it for means of adding strength to the concrete but for keeping walls in monolithic construction from overturning.<ref name= Condit>{{cite journal |last=Condit |first=Carl W. |journal=Technology and Culture |title=The First Reinforced-Concrete Skyscraper: The Ingalls Building in Cincinnati and Its Place in Structural History |date=January 1968 |volume=9 |issue=1 |pages=1–33 |doi=10.2307/3102041 |jstor=3102041|s2cid=113019875 }}</ref> The 1872–73 [[New York and Long Island Coignet Stone Company Building |Pippen Building]] in [[Brooklyn]], although not designed by Coignet, stands as a testament to his technique.
[[File:Maison de logement des ouvriers de l'usine Coignet 2020 6.jpg|thumb|{{ill| House built by Coignet for his factory workers |fr |Maison de logement des ouvriers de l'usine Coignet}} at 59-61 rue Charles-Michels, Saint Denis]]

In 1854, English builder William B. Wilkinson reinforced the concrete roof and floors in the two-story house he was constructing. His positioning of the reinforcement demonstrated that, unlike his predecessors, he had knowledge of tensile stresses.<ref>{{cite web |url=http://www.theconcreteproducer.com/Images/The%20History%20of%20Concrete%2C%20Part%202_tcm77-1306954.pdf |title= History of Concrete |year=1995 |author= Richard W. S |publisher= The Aberdeen Group |access-date= 25 April 2015 |archive-url=https://web.archive.org/web/20150528183822/http://www.theconcreteproducer.com/Images/The%20History%20of%20Concrete%2C%20Part%202_tcm77-1306954.pdf |archive-date= 28 May 2015 |url-status= dead |df=dmy-all}}</ref><ref>{{cite web |author= W. Morgan |title= Reinforced Concrete |work= The Elements of Structure |year= 1995 |via= John F. Claydon's website |url=http://www.jfccivilengineer.com/reinforced_concrete.htm |access-date= 25 April 2015 |archive-date= 12 October 2018 |archive-url=https://web.archive.org/web/20181012133730/http://www.jfccivilengineer.com/reinforced_concrete.htm |url-status= live}}</ref><ref name= CIVL1101>{{cite web |url= http://www.ce.memphis.edu/1101/notes/concrete/section_2_history.html |title= History of Concrete Building Construction |year= 2015 |website= CIVL 1101 – History of Concrete |author= Department of Civil Engineering |publisher= University of Memphis |access-date= 25 April 2015 |archive-date= 27 February 2017 |archive-url= https://web.archive.org/web/20170227213256/http://www.ce.memphis.edu/1101/notes/concrete/section_2_history.html |url-status= live }}</ref> Between 1869 and 1870, Henry Eton would design, and Messrs W & T Phillips of London construct the wrought iron reinforced [[Homersfield Bridge]], with a 50' (15.25 meter) span, over the river Waveney, between the English counties of Norfolk and Suffolk.<ref>{{NHLE|num=1262142|desc=  Homersfield Bridge |access-date = 26 March 2014}}</ref>

[[Joseph Monier]], a 19th-century French gardener, was a pioneer in the development of structural, prefabricated and reinforced concrete, having been dissatisfied with the existing materials available for making durable flowerpots.<ref>{{cite book |last=Day |first=Lance |title=Biographical Dictionary of the History of Technology |url=https://archive.org/details/isbn_9780415060424 |url-access=registration |page=[https://archive.org/details/isbn_9780415060424/page/284 284] |publisher=Routledge |year=2003 |isbn=0-203-02829-5}}</ref> He was granted a patent for reinforcing concrete flowerpots by means of mixing a wire mesh and a mortar shell in 1867.<ref>{{Britannica URL|biography/Joseph-Monier|Joseph Monier}}</ref> In 1877, Monier was granted another patent for a more advanced technique of reinforcing concrete columns and girders, using iron rods placed in a grid pattern. Though Monier undoubtedly knew that reinforcing concrete would improve its inner cohesion, it is not clear whether he even knew how much the [[Ultimate tensile strength|tensile strength]] of concrete was improved by the reinforcing.<ref name=Mörsch>{{cite book |last=Mörsch |first=Emil |title=Concrete-steel Construction: (Der Eisenbetonbau) |year=1909 |publisher=The Engineering News Publishing Company |pages=204–210}}</ref>

In 1877, [[Thaddeus Hyatt]] published a report entitled ''An Account of Some Experiments with Portland-Cement-Concrete Combined with Iron as a Building Material, with Reference to Economy of Metal in Construction and for Security against Fire in the Making of Roofs, Floors, and Walking Surfaces'',<ref>{{Cite book |last=Hyatt |first=Thaddeus |title=An Account of Some Experiments with Portland-cement-concrete Combined with Iron: As a Building Material, with Reference to Economy of Metal in Construction, and for Security Against Fire in the Making of Roofs, Floors, and Walking Surfaces |date=1877 |publisher=private circulation, at the Chiswick Press |url=https://books.google.com/books?id=yCZRAAAAYAAJ}}</ref> in which he reported his experiments on the behaviour of reinforced concrete. His work played a major role in the evolution of concrete construction as a proven and studied science. Without Hyatt's work, more dangerous trial and error methods might have been depended on for the advancement in the technology.<ref name= Condit/><ref>{{cite book |last=Collins |first=Peter |title=Concrete: The Vision of a New Architecture |date=1920–1981 |publisher=McGill-Queen's University Press |isbn=0773525645 |pages=58–60}}</ref>

Before the 1870s, the use of concrete construction, though dating back to the [[Roman Empire]], and having been reintroduced in the early 19th century, was not yet a scientifically proven technology.

[[Ernest L. Ransome]], an English-born engineer, was an early innovator of reinforced concrete techniques at the end of the 19th century. Using the knowledge of reinforced concrete developed during the previous 50 years, Ransome improved nearly all the styles and techniques of the earlier inventors of reinforced concrete. Ransome's key innovation was to twist the reinforcing steel bar, thereby improving its bond with the concrete.<ref name= Vision>{{cite book |last= Collins |first= Peter |title= Concrete: The Vision of a New Architecture |year= 2004 |orig-year= 1959 |edition= 2nd |publisher= McGill-Queen's University Press |isbn= 0773525645 |pages= 61–64 |url=https://books.google.com/books?id=7Zttxa_oHcEC&pg=PA61 |access-date= 27 March 2025}}</ref><ref>{{cite web| last=Mars |first= Roman |title= Episode 81: Rebar and the Alvord Lake Bridge |url=http://99percentinvisible.org/episode/episode-81-rebar-and-the-alvord-lake-bridge/| publisher= 99% Invisible |date=7 June 2013 |access-date=6 August 2014 |archive-date=8 August 2014 |archive-url=https://web.archive.org/web/20140808074102/http://99percentinvisible.org/episode/episode-81-rebar-and-the-alvord-lake-bridge/ |url-status= live}}</ref> Gaining increasing fame from his concrete constructed buildings, Ransome was able to build in 1886-1889 two of the first reinforced concrete bridges in North America.<ref name= Vision/>{{failed verification |No mention of any bridges |date= March 2025}} One of his [[Smith-Ransome Japanese Bridge|bridges]] still stands on [[Shelter Island, New York| Shelter Island]] in New York's East End.

One of the first concrete buildings constructed in the United States was a [[William E. Ward House|private home designed by William Ward]], completed in 1876. The home was particularly designed to be fireproof.

[[:de:Gustav Adolf Wayss|G. A. Wayss]] was a German civil engineer and a pioneer of the iron and steel concrete construction. In 1879, Wayss bought the German rights to Monier's patents and, in 1884, his firm, [[:de:Wayss & Freytag|Wayss & Freytag]], made the first commercial use of reinforced concrete. Up until the 1890s, Wayss and his firm greatly contributed to the advancement of Monier's system of reinforcing, established it as a well-developed scientific technology.<ref name=Mörsch/>

The [[Lamington Bridge]] was Australia's first large reinforced concrete road bridge. It was designed by [[Alfred Barton Brady]], who was the Queensland Government Architect at the time of the bridge's construction in 1896.<ref>{{Cite web |title= Lamington Bridge |publisher=[[Queensland Government]] |date=2016-08-31 |url=https://apps.des.qld.gov.au/heritage-register/explorer/detail/?id=600721 |access-date=2025-02-17}}</ref> It has eleven {{convert|15.2|m|adj=on}} spans and a total length of {{convert|187|m|adj=on}}, larger than any known comparable bridge in the world at that time.<ref>{{Cite web |title= Lamington Bridge, Mary River, 1896- |publisher=[[Engineers Australia]] |url=https://portal.engineersaustralia.org.au/heritage/lamington-bridge-mary-river-1896 |access-date=2025-02-17}}</ref>

One of the first [[skyscraper]]s made with reinforced concrete was the 16-story [[Ingalls Building]] in Cincinnati, constructed in 1904.<ref name= CIVL1101/>

The first reinforced concrete building in Southern California was the [[Homer Laughlin Building|Laughlin Annex]] in downtown [[Los Angeles]], constructed in 1905.<ref>{{Cite book |url=https://books.google.com/books?id=YmUUAAAAYAAJ |title=Los Angeles from the Mountains to the Sea |volume=2 |last=McGroarty |first=John Steven |publisher=American Historical Society |year=1921 |location=Los Angeles, CA |page=176 |access-date=2017-11-29 |archive-date=2016-08-09 |archive-url=https://web.archive.org/web/20160809190406/https://books.google.com/books?id=YmUUAAAAYAAJ |url-status=live }}</ref><ref>{{Cite book |title=Annual Report of the City Auditor, City of Los Angeles, California for the Year Ending June 30 |publisher=Los Angeles City Auditor |year=1905 |location=Los Angeles, CA |pages=71–73  }}</ref> In 1906, 16 building permits were reportedly issued for reinforced concrete buildings in the City of Los Angeles, including the [[Hazard's Pavilion#Clune's Auditorium|Temple Auditorium]] and 8-story Hayward Hotel.<ref>{{Cite journal |last=Williams |first=D. |date=February 1907 |title=What Builders are Doing |url=https://books.google.com/books?id=oidPAAAAYAAJ&pg=PA66 |journal=Carpentry and Building |page=66 |access-date=2017-11-29 |archive-date=2020-09-01 |archive-url=https://web.archive.org/web/20200901135940/https://books.google.com/books?id=oidPAAAAYAAJ&pg=PA66 |url-status=live }}</ref><ref>{{Cite journal |author=W.P.H. |date=April 19, 1906 |title=Reinforced Concrete Buildings at Los Angeles, Cal. |url=https://books.google.com/books?id=jg1HAQAAMAAJ&pg=449 |journal=Engineering News-Record |volume=55 |page=449 |department=Letters to the Editor |access-date=November 29, 2017 |archive-date=September 19, 2020 |archive-url=https://web.archive.org/web/20200919094412/https://books.google.com/books?id=jg1HAQAAMAAJ&pg=449 |url-status=live }}</ref>

In 1906, a partial collapse of the Bixby Hotel in Long Beach killed 10 workers during construction when shoring was removed prematurely. That event spurred a scrutiny of concrete erection practices and building inspections. The structure was constructed of reinforced concrete frames with hollow clay tile ribbed flooring and hollow clay tile infill walls. That practice was strongly questioned by experts and recommendations for "pure" concrete construction were made, using reinforced concrete for the floors and walls as well as the frames.<ref>{{Cite magazine |author1=Austin, J. C. |author2=Neher, O. H. |author3=Hicks, L. A. |author4=Whittlesey, C. F. |author5=Leonard, J. B. |date=November 1906 |title=Partial Collapse of the Bixby Hotel at Long Beach |url=https://books.google.com/books?id=17dCAQAAMAAJ&pg=PA44 |magazine=Architect and Engineer of California |volume=VII |issue=1 |pages=44–48 |access-date=2018-05-29 |archive-date=2020-09-20 |archive-url=https://web.archive.org/web/20200920184843/https://books.google.com/books?id=17dCAQAAMAAJ&pg=PA44 |url-status=live }}</ref>

In April 1904, [[Julia Morgan]], an American architect and engineer, who pioneered the aesthetic use of reinforced concrete, completed her first reinforced concrete structure, El Campanil, a {{convert|72|ft|adj=on}} bell tower at [[Mills College]],<ref name= Campanil>{{cite web|title=El Campanil, Mills College: Julia Morgan 1903-1904|url=https://www.bluffton.edu/homepages/facstaff/sullivanm/jmmills/jmcampanil.html|access-date=18 April 2019|archive-date=30 December 2018|archive-url=https://web.archive.org/web/20181230165410/http://www.bluffton.edu/homepages/facstaff/sullivanm/jmmills/jmcampanil.html|url-status=live}}</ref> which is located across the bay from [[San Francisco]].  Two years later, El Campanil survived the [[1906 San Francisco earthquake]] without any damage,<ref name= morgan>{{cite web |last1=Callen |first1=Will |date=4 February 2019 |title=Julia Morgan-designed Mills bell tower counts down to its 115th anniversary |url=https://hoodline.com/2019/02/julia-morgan-designed-bell-tower-counts-down-to-its-115th-anniversary |access-date=18 April 2019 |publisher=hoodline.com }}</ref> which helped build her reputation and launch her prolific career.<ref name= busnow>{{cite web| last1=Littman| first1=Julie| date=7 March 2018| title=Bay Area Architect Julia Morgan's Legacy Wasn't Just Hearst Castle| url=https://www.bisnow.com/san-francisco/news/commercial-real-estate/bay-area-architect-julia-morgans-legacy-wasnt-just-hearst-castle-85824| access-date=18 April 2019| publisher=busnow.com| archive-date=20 April 2019| archive-url=https://web.archive.org/web/20190420045748/https://www.bisnow.com/san-francisco/news/commercial-real-estate/bay-area-architect-julia-morgans-legacy-wasnt-just-hearst-castle-85824| url-status=live}}</ref> The 1906 earthquake also changed the public's initial resistance to reinforced concrete as a building material, which had been criticized for its perceived dullness. In 1908, the [[San Francisco Board of Supervisors]] changed the city's [[building code]]s to allow wider use of reinforced concrete.<ref>{{Cite web| last=Olsen| first=Erik| date=1 May 2020| title=How one building survived the San Francisco earthquake and changed the world| url=https://californiascienceweekly.com/2020/04/30/how-one-building-survived-the-san-francisco-earthquake-and-changed-the-world/| url-status=dead| archive-url=https://web.archive.org/web/20200702204631/https://californiascienceweekly.com/2020/04/30/how-one-building-survived-the-san-francisco-earthquake-and-changed-the-world/| archive-date=2 July 2020| access-date=1 July 2020| publisher=California Science Weekly}}</ref>

In 1906, the National Association of Cement Users (NACU) published ''Standard No. 1''<ref>{{Cite book |title=Standard Specifications for Portland Cement of the American Society for Testing Materials, Standard No. 1 |publisher=National Association of Cement Users |year=1906 |location=Philadelphia, PA}}</ref> and, in 1910, the ''Standard Building Regulations for the Use of Reinforced Concrete''.<ref>{{Cite book |title=Standard Building Regulations for the Use of Reinforced Concrete |publisher=National Association of Cement Users |year=1910 |location=Philadelphia, PA}}</ref>