Editing Tunnel boring machine (section)

== History ==
<div style="float:right;clear:right;">
[[File:Hamburg.Trude.wmt.jpg|thumb|Cutting shield used for the [[New Elbe Tunnel]]]]
[[File:Tunnelier mp3h8085.jpg|thumb|Looking towards the cutting shield at the hydraulic jacks]]
[[File:Sydney Metro - Barangaroo - TBM Kathleen Cutterhead - Flickr - john cowper.jpg|thumb|A tunnel boring machine cutter head being lowered underground for the construction of the [[Sydney Metro City & Southwest|City & Southwest]] line of the [[Sydney Metro]]]]
</div>

=== 1800s ===
The [[tunnelling shield#History|first successful tunnelling shield]] was developed by Sir [[Marc Isambard Brunel]] to excavate the [[Thames Tunnel]] in 1825. However, this was only the invention of the shield concept and did not involve the construction of a complete tunnel boring machine, the digging still having to be accomplished by the then standard excavation methods.{{sfn|Bagust|2006|p=65}}

The first boring machine reported to have been built was [[Henri Maus]]' ''Mountain Slicer''.{{sfn|Drinker|1883|pp=[https://archive.org/details/atreatiseonexpl00dringoog/page/n207 191-194]}}<!--Maus' Slicer makes no appearance in Bancroft! And 58 is journal volume number, not a page no. {{sfn|Bancroft|1908|p=58}}-->{{sfn|West|1988}}{{page needed|date=April 2025}}{{sfn|Maidl et al.|2008}}{{sfn|Hemphill|2013}} Commissioned by the [[Charles Albert of Sardinia|King of Sardinia]] in 1845 to dig the [[Fréjus Rail Tunnel]] between France and Italy through the [[Alps]], Maus had it built in 1846 in an arms factory near [[Turin]]. It consisted of more than 100 percussion drills mounted in the front of a locomotive-sized machine, mechanically power-driven from the entrance of the tunnel. The [[Revolutions of 1848]] affected the funding, and the tunnel was not completed until 10 years later, by using less innovative and less expensive methods such as [[Jackhammer|pneumatic drills]].<ref name="Ref_">[http://www.mindfully.org/Technology/2004/Underground-Boring-Machines1sep04.htm Hapgood, Fred, "The Underground Cutting Edge: The innovators who made digging tunnels high-tech",''Invention & Technology'' Vol.20, #2, Fall 2004] {{Webarchive|url=https://web.archive.org/web/20050315045158/http://www.mindfully.org/Technology/2004/Underground-Boring-Machines1sep04.htm |date=2005-03-15 }}</ref>

In the United States, the first boring machine to have been built was used in 1853 during the construction of the [[Hoosac Tunnel]] in northwest Massachusetts.{{sfn|Maidl et al.|2008|p=1}} Made of cast iron, it was known as ''Wilson's Patented Stone-Cutting Machine'', after inventor Charles Wilson.<ref>{{cite web|last=Smith|first=Gary|title=FINDING AID FOR THE HOOSAC TUNNEL COLLECTION at the NORTH ADAMS PUBLIC LIBRARY|url=http://www.naplibrary.com/HTHistoricNotes.html|archive-url=https://web.archive.org/web/20040115130100/http://naplibrary.com/HTHistoricNotes.html|url-status=dead|archive-date=15 January 2004|work=Hooac Tunnel Historical Notes|publisher=North Adams Public Library|access-date=14 July 2011}}</ref> It drilled {{convert|10|ft|0|order=flip|sp=us}} into the rock before breaking down (the tunnel was eventually completed more than 20 years later, and as with the Fréjus Rail Tunnel, by using less ambitious methods).<ref>{{cite web|last=Howes|first=M|url=http://www.hoosactunnel.net/historytimeline.php|title=Hoosac Tunnel History - Abridged Timeline|access-date=14 July 2011|archive-date=21 May 2011|archive-url=https://web.archive.org/web/20110521001435/http://hoosactunnel.net/historytimeline.php|url-status=dead}}</ref> Wilson's machine anticipated modern TBMs in the sense that it employed cutting discs, like those of a [[disc harrow]], which were attached to the rotating head of the machine.<ref name=Bancroft65>Bancroft 1908, p. 65</ref><ref>Wilson, Charles. "Dressing stone," {{US patent|5,012}} (issued: March 13, 1847).</ref><ref>Wilson, Charles. "Machine for tunneling rocks, etc.," {{US patent|14,483}} (issued: March 18, 1856).</ref> In contrast to traditional chiseling or drilling and blasting, this innovative method of removing rock relied on simple metal wheels to apply a transient high pressure that fractured the rock.{{cn|date=April 2025}}

In 1853, the American Ebenezer Talbot also patented a TBM that employed Wilson's cutting discs, although they were mounted on rotating arms, which in turn were mounted on a rotating plate.<ref>Talbot, Ebenezer. "Machine for tunnelling or boring rock," {{US patent|9,774}} (issued:  June 7, 1853).</ref> In the 1870s, John D. Brunton of England built a machine employing cutting discs that were mounted eccentrically on rotating plates, which in turn were mounted eccentrically on a rotating plate, so that the cutting discs would travel over almost all of the rock face that was to be removed.{{sfn|West|1988|pp=239-242}}<ref>Brunton, John D. "Improved machine for sinking shafts," {{US patent|80,056}} (issued:  July 21, 1868).</ref>

The first TBM that tunneled a substantial distance was invented in 1863 and improved in 1875 by British Army officer Major [[Frederick Beaumont|Frederick Edward Blackett Beaumont]] (1833–1895); Beaumont's machine was further improved in 1880 by British Army officer Major Thomas English (1843–1935).{{sfn|West|1988|pp=243-247}}<ref>David William Brunton and John Allen Davis, ''Modern Tunneling: With Special Reference to Mine and Water-supply Tunnels'' (New York, New York:  John Wiley & Sons, 1914), [https://books.google.com/books?id=HZ9BAAAAIAAJ&pg=PA182 p. 182.]</ref><ref>Frederick Edward Blackett Beaumont, U.K. Patent no. 1,904 (issued:  July 30, 1864).  (See:  ''Patents for Inventions.  Abridgments of Specifications relating to Mining, Quarrying, Tunnelling, and Well-sinking'' (London, England:  Office of the Commissioners of Patents for Inventions, 1874), [https://books.google.com/books?id=jXNUAAAAYAAJ&pg=RA1-PA247 p. 247.] {{Webarchive|url=https://web.archive.org/web/20230728205702/https://books.google.com/books?id=jXNUAAAAYAAJ&pg=RA1-PA247 |date=2023-07-28 }})</ref><ref>F.E.B. Beaumont, U.K. Patent no. 4,166 (issued:  Dec. 2, 1875).  (See:  ''Patents for Inventions.  Abridgments of Specifications.  Class 85, Mining, Quarrying, Tunnelling, and Well-sinking'' (London, England:  Patent Office, 1904), [https://books.google.com/books?id=UdhOAAAAYAAJ&pg=RA1-PA169 p. 169.] {{Webarchive|url=https://web.archive.org/web/20230728205627/https://books.google.com/books?id=UdhOAAAAYAAJ&pg=RA1-PA169 |date=2023-07-28 }})</ref><ref>Thomas English, U.K. Patent no.s 4,347 (issued:  October 25, 1880) and 5,317 (issued:  December 5, 1881); "Tunneling-machine," {{US patent|307,278}} (filed: June 4, 1884 ; issued: October 28, 1884).</ref> In 1875, the French National Assembly approved the construction of a tunnel under the [[English Channel]] and the [[British Parliament]] supported a trial run using English's TBM. Its cutting head consisted of a conical drill bit behind which were a pair of opposing arms on which were mounted cutting discs. From June 1882 to March 1883, the machine tunneled, through chalk, a total of 1,840&nbsp;m (6,036&nbsp;ft).{{sfn|Hemphill|2013}} A French engineer, [[Alexandre Lavalley]], who was also a [[Suez Canal Company|Suez Canal contractor]], used a similar machine to drill 1,669&nbsp;m (5,476&nbsp;ft) from [[Sangatte]] on the French side.<ref>{{cite book |last1=Wilson |first1=Jeremy |last2=Spick |first2=Jérôme |title=Eurotunnel: The Illustrated Journey |date=1994 |publisher=Harper Collins |location=New York, NY, USA |isbn=0-00-255539-5 |pages=14–21}}</ref> However, despite this success, the cross-Channel tunnel project was abandoned in 1883 after the British military raised fears that the tunnel might be used as an invasion route.{{sfn|Hemphill|2013}}<ref>Terry Gourvish, ''The Official History of Britain and the Channel Tunnel'' (Abington, England: Routledge, 2006), Chapter 1, § 2: The commercial possibilities:  Lord Richard Grosvenor, Sir Edward Watkin and the 'Manchester to Paris Railroad'.</ref> Nevertheless, in 1883, this TBM was used to bore a railway ventilation tunnel — {{cvt|7|ft|m|order=flip|0}} in diameter and {{cvt|6750|ft|km|order=flip}} long — between [[Birkenhead]] and [[Liverpool]], England, through sandstone under the [[River Mersey|Mersey River]].{{sfn|West|1988|p=248}}

The [[North River Tunnels|Hudson River Tunnel]] was constructed from 1889 to 1904 using a Greathead shield TBM. The project used air compressed to {{cvt|35|psi|bar|order=flip}} to  reduce cave-ins. However, there were many workers that died via cave-in or decompression sickness.<ref>{{Cite web |last=American Society of Civil Engineers |title=Hudson and Manhattan Railroad Tunnel |url=https://www.asce.org/about-civil-engineering/history-and-heritage/historic-landmarks/hudson-and-manhattan-railroad-tunnel |access-date=2023-10-17 |website=www.asce.org |language=en-US}}</ref><ref>{{Cite web |title=ASCE Metropolitan Section - Hudson & Manhattan Tunnel |url=https://www.ascemetsection.org/committees/history-and-heritage/landmarks/hudson-manhattan-tunnel |access-date=2023-10-17 |website=www.ascemetsection.org}}</ref>{{Sfn|Potter|2023}}

=== 1900s ===
During the late 19th and early 20th century, inventors continued to design, build, and test TBMs for tunnels for railroads, subways, sewers, water supplies, etc. TBMs employing rotating arrays of drills or hammers were patented.<ref>See:
* Bancroft 1908, pp. 66, 125, 127, 146.
*Thales Lindsey, "Improved machine for tunneling rock," {{US patent|55,514}} (issued: June 12, 1866).
*Pedro Unanue, "Tunneling machine," {{US patent|732,326}} (filed: December 23, 1901; issued: June 30, 1903).
*Russell B. Sigafoos, "Rotary tunneling machine," {{US patent|901,392}} (filed: May 18, 1907; issued: October 20, 1908).
*George A. Fowler, "Tunnel driving machine," {{US patent|891,473}} (filed: July 30, 1907 ; issued: June 23, 1908).</ref> TBMs that resembled giant [[hole saw]]s were proposed.<ref>See:
* Bancroft 1908, pp. 66, 85, 106.
* Wilson, Charles. Machine for excavating tunnels," {{US patent|17,650}} (issued: June 23, 1857).
* Stanley, Reginald. U.K. Patent no. 1,449 (issued: February 1, 1886); "Tunneling-machine" (issued: August 7, 1894).
* Mitchell, Jonas L. "Tunneling-machine," {{US patent|537,899}} (filed: April 3, 1893 ; issued: April 23, 1895).</ref> Other TBMs consisted of a rotating drum with metal tines on its outer surface,<ref>See:
*William F. Cooke and George Hunter, U.K. patent no. 433 (issued: August 10, 1866). Available online at: [http://www.aditnow.co.uk/documents/personal-album-54/Tunnelerpatent2.pdf AditNow] {{Webarchive|url=https://web.archive.org/web/20160304195336/http://www.aditnow.co.uk/documents/personal-album-54/Tunnelerpatent2.pdf |date=2016-03-04 }}.
*''Patents for Inventions. bridgments of Specifications relating to Mining, Quarrying, Tunnelling, and Well-sinking'' (London, England: Office of the Commissioners of Patents for Inventions, 1874), [https://books.google.com/books?id=jXNUAAAAYAAJ&pg=RA1-PA275 p. 275.] {{Webarchive|url=https://web.archive.org/web/20230728205632/https://books.google.com/books?id=jXNUAAAAYAAJ&pg=RA1-PA275 |date=2023-07-28 }}
*{{harvnb|Maidl et al.|2008}}</ref> or a rotating circular plate covered with teeth,<ref>See:
* Bancroft 1908, pp. 146, 165.
*John P. Karns, "Tunneling-machine," {{US patent|848,107}} (filed: November 29, 1905; issued: March 26, 1907).
*Olin S. Proctor, "Tunneling-machine," {{US patent|900,951}} (filed: February 17, 1908; issued: October 13, 1908).</ref> or revolving belts covered with metal teeth.<ref>See:
* Bancroft 1908, p. 145.
*William A. Lathrop, "Machine for cutting headings," {{US patent|816,923}} (filed: August 31, 1903; issued: April 3, 1906).</ref> However, these TBMs proved expensive, cumbersome, and unable to excavate hard rock; interest in TBMs therefore declined. Nevertheless, TBM development continued in potash and coal mines, where the rock was softer.<ref>For example:
*In Germany, the ''Eisener Bergmann'' (iron miner) was developed in 1916 by Schmidt, Kranz & Co. for potash mines; its boring head consisted of a large rotating roller that was fitted with cutters  See: {{harvnb|Maidl et al.|2008}}
*In the U.S., the McKinlay Entry Driver, a track-mounted TBM or "continuous miner", was invented in 1918 for use in coal mines.  Its boring head consisted of metal tines on two, side-by-side rotating arms. See: Thomas W. Garges (November 13, 2003) William N. Poundstone lecture: "Underground Mining Technology Evolution", p. 8. Available online at:  [http://www2.cemr.wvu.edu/~wwwmine/poundstonelec/GargesThomastxt.pdf Benjamin M. Statler College of Engineering and Mineral Resources, West Virginia University] {{Webarchive|url=https://web.archive.org/web/20161020162943/http://www2.cemr.wvu.edu/~wwwmine/poundstonelec/GargesThomastxt.pdf |date=2016-10-20 }}</ref>

A TBM with a bore diameter of {{convert|14.4|m|ftin|abbr=on}} was manufactured by The Robbins Company for Canada's [[Niagara Tunnel Project]]. The machine was used to bore a hydroelectric tunnel beneath [[Niagara Falls]]. The machine was named "Big Becky" in reference to the Sir [[Adam Beck]] hydroelectric dams to which it tunnelled to provide an additional hydroelectric tunnel.

=== 2000s ===
[[File:TBM S-210 Alptransit Faido East.jpg|thumb|A tunnel boring machine used to excavate the [[Gotthard Base Tunnel]], Switzerland, the world's longest rail tunnel]]
The TBM known as [[Bertha (tunnel boring machine)|Bertha]], reportedly the largest [[earth pressure balance]] machine and second largest TBM in general (as of June 2023), has a bore diameter of {{convert|17.45|m|ft|sp=us}}, and was produced by [[Hitachi Zosen Corporation]] in 2013.{{Sfn|Cecere|2023}}<ref>{{Cite web |title=Shield Tunneling Machines |url=https://www.hitachizosen.co.jp/english/business/field/infrastructure/shield.html |url-status=live |archive-url=https://web.archive.org/web/20230123075040/https://www.hitachizosen.co.jp/english/business/field/infrastructure/shield.html |archive-date=2023-01-23 |access-date=2023-02-04 |website=Hitachi Zosen Corporation |language=en}}{{full|date=April 2025}}{{third party inline|date=April 2025}}</ref>{{better source|date=April 2025}} It was delivered to [[Seattle]], [[Washington (state)|Washington]], for its [[Alaskan Way Viaduct replacement tunnel|Highway 99 tunnel project]].<ref>{{cite web|url=http://www.wsdot.wa.gov/projects/Viaduct/|title=Alaskan Way Viaduct - Home|website=www.wsdot.wa.gov|access-date=21 July 2017|archive-date=28 July 2023|archive-url=https://web.archive.org/web/20230728205631/https://wsdot.wa.gov/construction-planning/major-projects/alaskan-way-viaduct-replacement-program|url-status=live}}{{full|date=April 2025}}</ref>{{full|date=April 2025}} The machine began operating in July 2013, but stalled in December 2013 and required substantial repairs that halted the machine until January 2016.<ref>{{cite magazine|author = Weise, Karen |date = 2016-01-06 | title=Bertha the Giant Drill Is Ready to Rumble in Seattle| magazine=Bloomberg Businessweek (Bloomberg.com) |url=https://www.bloomberg.com/news/articles/2016-01-06/bertha-the-giant-drill-is-ready-to-rumble-in-seattle/ | access-date=21 July 2017| archive-url=https://web.archive.org/web/20160309015129/http://www.bloomberg.com/news/articles/2016-01-06/bertha-the-giant-drill-is-ready-to-rumble-in-seattle | archive-date = 2016-03-09 | url-access = }}</ref> Bertha completed boring the tunnel on April 4, 2017.<ref>{{Cite web |date=2017-04-06 |title=Alaskan Way Viaduct - Recapping Bertha's breakthrough |url=https://www.wsdot.wa.gov/Projects/Viaduct/library/advisories-and-updates/recapping-berthas-breakthrough |url-status=dead |archive-url=https://web.archive.org/web/20170901063417/http://www.wsdot.wa.gov/Projects/Viaduct/library/advisories-and-updates/recapping-berthas-breakthrough |archive-date=2017-09-01 |website=[[Washington State Department of Transportation]]}}{{full|date=April 2025}}</ref>{{full|date=April 2025}}

Two TBMs supplied after the 2013 acquisition of Germany's Aker Wirth (Aker Solutions) TBM and shaft-boring technology by China Railway Tunnelling Equipment (CRTE), now CREG (China Railway Engineering Equipment Group)-Germany,<ref>{{cite web | author = IM Staff | date =  29 November 2013 | title = Aker Sells TBM and Shaft Sinking Businesses to China's CRTE | work = International Mining (IM, IM-Mining.com) | url = https://im-mining.com/2013/11/29/aker-seels-underground-development-business-to-chinas-crte/ | access-date = 22 April 2025 | location = Berkhamsted, England| publisher = IM Team Publishing}} Note, the acquisition was sans Wirth's newer Mobile Tunnel Miner technology developed with [[Codelco]] and [[Rio Tinto (corporation)|Rio Tinto]], see article.</ref><ref name=CREGWirthTBM2017>{{Cite web | author = CREG-Wirth Staff | date = 2017-09-09 | title = Earth Pressure Balance | work = [[CREG-Germany]].com | format = manufacturer's commercial site | url = http://www.creg-germany.com/products_tunnel-boring-machines_epb-machine.php#tab-c-03 | access-date = 22 April 2025 | url-status=dead |archive-url=https://web.archive.org/web/20170909054126/http://www.creg-germany.com/products_tunnel-boring-machines_epb-machine.php#tab-c-03 |archive-date=2017-09-09 | at=Metro Kuala Lumpur, Malaysia > Project; and Metro Kuala Lumpur, Malaysia > Tech Specs | location = Erkelenz, Germany | publisher = CREG TBM Germany GmbH}}{{third party inline|date=April 2025}}</ref>{{better source|date=April 2025}} CREG-Wirth units with boring diameter of {{cvt|6.67|m|ft}}, were used to bore two tunnels for [[Kuala Lumpur]], [[Malaysia]]'s Metro system.<ref name=CREGWirthTBM2017/>{{better source|date=April 2025}} The medium excavated was water "saturated sandy mudstone, schistose mudstone, highly weathered mudstone as well as alluvium".<ref name=CREGWirthTBM2017/>{{better source|date=April 2025}} By the company's commercial description, its products achieved an advance rate of "more than 345 meters [1,130 feet] per month".<ref name=CREGWirthTBM2017/>{{better source|date=April 2025}}
[[File:Tunnelier mp3h8086.jpg|thumb|Top view of a model of the TBM{{what|date=April 2025}} used on the [[Gotthard Base Tunnel]].{{cn|date=April 2025}}]]

Reportedly the largest ''hard rock'' machine and fourth largest TBM overall (as of June 2023), a machine known as [[Martina (tunnel boring machine)|Martina]], was built by [[Herrenknecht|Herrenknecht AG]].{{Sfn|Cecere|2023}} Its excavation diameter is {{convert|15.62|m|ft|abbr=on}}, and total length {{convert|130|m|ft|abbr=on}}; excavation area of {{convert|192|sqm|sqft|abbr=on}}, and thrust value 39,485&nbsp;t,{{what|date=April 2025}}<!--Unit needs to be spelled out--> total weight 4,500&nbsp;tons, and total installed capacity 18&nbsp;MW.{{Sfn|Cecere|2023}} Its yearly energy consumption was about 62&nbsp;GWh.{{Sfn|Cecere|2023}} Martina was used by the Italian Toto Group construction company (Toto S.p.A Costruczioni General) to bore a 2.4 km tunnel of the Variante di Valico project near Florence, Italy, in 2013. This project created the Sparvo gallery of the Italian Motorway Pass A1 ("Variante di Valico A1"), near Florence.{{cn|date=April 2025}} As of this date,{{when|date=April 2025}} Martina was still owned and operated by the Toto Group.{{cn|date=April 2025}} 

Herrenknecht also built the world's largest-diameter [[Tuen Mun-Chek Lap Kok TBM|slurry TBM]] and as of June 2023, per ''[[Guinness World Records]]'', also the largest TBM overall; called the "Qin Liangyu" or Mixshield S-880, it has an excavation diameter of {{convert|17.63|m|ft|sp=us}}.{{Sfn|Cecere|2023}} Owned and operated by a subsidiary of the French construction company Bouygues (Dragages Hong Kong), it was used to bore the Chek Lap Kok to Tuen Mun road tunnel, undersea, to  [[Hong Kong]], China, clearing the first section of the tunnel at the large diameter, then being converted to 14 m, and working alongside 3 other TBMs (including another Herrenknect borer) to complete the tunnels, 30 m undersea, in 2019.{{Sfn|Cecere|2023}}