|
A tunnel boring machine (TBM), also known as a "mole", is a machine used to excavate tunnels with a circular cross section through a variety of soil and rock strata. It may also be used for microtunneling. They can bore through anything from hard rock to sand. Tunnel diameters can range from a metre (done with micro-TBMs) to 19.25 metres to date. Tunnels of less than a metre or so in diameter are typically done using trenchless construction methods or horizontal directional drilling rather than TBMs. Tunnel boring machines are used as an alternative to drilling and blasting (D&B) methods in rock and conventional "hand mining" in soil. TBMs have the advantages of limiting the disturbance to the surrounding ground and producing a smooth tunnel wall. This significantly reduces the cost of lining the tunnel, and makes them suitable to use in heavily urbanized areas. The major disadvantage is the upfront cost. TBMs are expensive to construct, and can be difficult to transport. However, as modern tunnels become longer, the cost of tunnel boring machines versus drill and blast is actually less. This is because tunneling with TBMs is much more efficient and results in shortened completion times. Herrenknecht AG built the world's largest diameter hard rock TBM: "Martina" (excavation diameter of 15.62 m, total length 130 m; excavation area of 192 square m, thrust value 39,485 t, total weight 4,500 tons, total installed capacity 18 MW; yearly energy consumption about 62,000,000 kWh) is owned and operated by the Italian construction company Toto S.p.A. Costruzioni Generali (Toto Group) for the Sparvo gallery of the Italian Motorway Pass A1 ("Variante di Valico A1"), near Florence. The former largest diameter hard rock TBM, at 14.4 m, 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 is tunnelling to provide an additional hydroelectric tunnel. In 2013, Hitachi Zosen Corporation delivered an earth pressure balance TBM to Seattle, Washington, for the Highway 99 tunnel project.〔(Alaskan Way Viaduct - Home )〕 The bore is .〔(Shield Tunneling Machines )〕 The machine, named Bertha, has been stalled since December 2013 and remains under repair .〔(Bertha's Stall has politicians stuck for answers. )〕 == History == The 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. The first boring machine reported to have been built was Henri-Joseph Maus's ''Mountain Slicer''. Commissioned by the 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 pneumatic drills.〔(Hapgood, Fred, "The Underground Cutting Edge: The innovators who made digging tunnels high-tech",''Invention & Technology'' Vol.20, #2, Fall 2004 )〕 In the United States, the first boring machine to have been built was used in 1853 during the construction of the Hoosac Tunnel. Made of cast iron, it was known as ''Wilson's Patented Stone-Cutting Machine'', after inventor Charles Wilson. It drilled 10 feet 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.) 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.〔Charles Wilson, "Dressing stone," (issued: March 13, 1847).〕〔Charles Wilson, "Machine for tunneling rocks, etc.," (issued: March 18, 1856).〕 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. Also 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.〔Ebenezer Talbot, "Machine for tunnelling or boring rock," (issued: June 7, 1853).〕 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.〔John D. Brunton, "Improved machine for sinking shafts," (issued: July 21, 1868).〕 The first TBM that tunneled a substantial distance was invented in 1863 and improved in 1875 by British Army officer Major Frederick Edward Blackett Beaumont (1833-1895); Beaumont's machine was further improved in 1880 by British Army officer Major Thomas English (1843-1935).〔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), (p. 182. )〕〔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), (p. 247. ))〕〔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), (p. 169. ))〕〔Thomas English, U.K. Patent no.s 4,347 (issued: October 25, 1880) and 5,317 (issued: December 5, 1881); "Tunneling-machine," (filed: June 4, 1884 ; issued: October 28, 1884).〕 In 1875 the French National Assembly approved the construction of a tunnel under the English Channel and the British Parliament allowed a trail run to be made; English's TBM was chosen for the project. The cutting head of English's TBM 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 6,036 feet (1.84 km). 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.〔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'.〕 Nevertheless, in 1883, this TBM was used to bore a railway ventilation tunnel — 7 feet (2.1 m) in diameter and 6,750 feet (2 km) long — between Birkenhead and Liverpool, England, through sandstone under the Mersey River. During the late 19th and early 20th century, inventors continued to design, build, and test TBMs in response to the need for tunnels for railroads, subways, sewers, water supplies, etc. TBMs employing rotating arrays of drills or hammers were patented.〔See: * * Thales Lindsey, "Improved machine for tunneling rock," (issued: June 12, 1866). * Pedro Unanue, "Tunneling machine," (filed: December 23, 1901; issued: June 30, 1903). * Russell B. Sigafoos, "Rotary tunneling machine," (filed: May 18, 1907; issued: October 20, 1908). * George A. Fowler, "Tunnel driving machine," (filed: July 30, 1907 ; issued: June 23, 1908).〕 TBMs that resembled giant hole saws were proposed.〔See: * * Charles Wilson, Machine for excavating tunnels," (issued: June 23, 1857). * Reginald Stanley, U.K. Patent no. 1,449 (issued: February 1, 1886); "Tunneling-machine" (issued: August 7, 1894). * Jonas L. Mitchell, "Tunneling-machine," (filed: April 3, 1893 ; issued: April 23, 1895).〕 Other TBMs consisted of a rotating drum with metal tines on its outer surface,〔See: * William F. Cooke and George Hunter, U.K. patent no. 433 (issued: August 10, 1866). Available online at: (AditNow ). * ''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), (p. 275. ) * 〕 or a rotating circular plate covered with teeth,〔See: * * John P. Karns, "Tunneling-machine," (filed: November 29, 1905; issued: March 26, 1907). * Olin S. Proctor, "Tunneling-machine," (filed: February 17, 1908; issued: October 13, 1908).〕 or revolving belts covered with metal teeth.〔See: * * William A. Lathrop, "Machine for cutting headings," (filed: August 31, 1903; issued: April 3, 1906).〕 However, all of 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.〔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: * 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]〕 The first successful use was on the Oahe Dam in 1952 by James S Robbins. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tunnel boring machine」の詳細全文を読む スポンサード リンク
|