|
Aldeadávila Dam is a concrete arch-gravity dam on the Douro River (also known as the Duero River) on the border between Spain and Portugal.〔(''Hydraulic Model Studies of Amaluza Dam Spillway.'' GR-25-76. Hydraulics Branch. Division of General Research. Engineering and Research Center. Bureau of Reclamation. United States Department of the Interior. December 1976, p. 9. )〕 The Douro River forms the international boundary between Portugal and Spain. The nearest Spanish town is Aldeadávila de la Ribera in the Province of Salamanca, about to the east. The nearest Portuguese town is Fornos in Bragança District, about to the southwest. The Portuguese side of the river around the dam site lies within the International Douro Natural Park. ==Overview== In 1864, Portugal and Spain signed the "Treaty of Limits" (ratified in 1866), which established the present international boundaries of the two nations.〔(Dominguez, Damian; Manser, Reto; and Ort, Christoph. ''No Problems on Río Duero (Spain) - Rio Douro (Portugal)?'' Swiss Federal Institute of Technology Zurich. 2004, p. 9-10. ) Accessed 2010-07-24; Martínez, José María Santafé. "The Spanish-Portuguese Transboundary Waters Agreements: Historic Perspective." ''Water International.'' 28:3 (September 2003).〕〔Fitzmaurice, Malgosia. ''Exploitation of Natural Resources in the 21st Century.'' The Hague: Kluwer Law International, 2003, p. 196.〕 A treaty on transboundary rivers, clarifying issues regarding the use of such rivers, was signed and affirmed in 1912.〔 A treaty regulating the development of hydroelectric facilities on the Douro River was signed in 1927.〔 The Aldeadávila Dam was built by Spain pursuant to these treaties, and was the final dam to be built by Spain on the section of river allotted to that country.〔 The dam is high〔 and its cost was estimated in 1962 at US$60,000,000 (about $443.5 million in 2010 inflated-adjusted dollars).〔 It was one of a series of very high dams built in Europe in the two decades after World War II; these were designed with a downstream face inclined toward the upstream flow.〔 This simplified the dam's design and construction (although it required more concrete to build), and more readily incorporated the spillways into the dam face.〔 The dam's face is nearly vertical.〔Serebryanskii, V.M. "Engineering Bases of the Architecture of Hydraulic Developments With Arch Dams," ''Hydrotechnical Construction.'' 7:7 (July 1973), p. 660.〕 Design work on the dam began in 1956, and construction completed in 1963.〔 The structure was built by the Iberdrola Ingeniería y Construcción construction firm. Pedro Martínez Artola was the design engineer.〔Rubió, Ignasi Solà-Morales; Capitel, Antón; and Rispa, Raúl. ''Birkhäuser Architectural Guide: Spain, 1920-1999.'' Basel: Birkhäuser, 1998, p. 126.〕 The dam was built on high-quality granite rock.〔Stagg, Kenneth G. and Zienkiewicz, O. ''Rock Mechanics in Engineering Practice.'' New York: John Wiley & Sons, 1968, p. 423.〕 During construction, grouting was used to fill cracks in the rock which ran parallel to the dam's foundation, and on the Portuguese bank where two fractures in the rock occurred.〔〔Judd, William R. ''State of Stress in the Earth's Crust: Proceedings of the International Conference, 1963.'' New York: Elsevier Pub. Co., 1964, p. 640.〕 The underground power station and tunnels were excavated using a mining procedure known as large-chamber stoping. The use of this technique for the Aldeadávila Dam is considered a textbook example.〔Jimeno, E. Lopez; Jimino, C. Lopez; and Carcedo, Ayala. ''Drilling and Blasting of Rocks.'' New York: Taylor & Francis, 1994, p. 250.〕 The turbine and generator hall, and the transformer hall were both cut from solid granite as well. The turbine and generator room is long, wide, and deep.〔 The total volume of excavated material for all halls, rooms, and abutments was .〔 The structure has eight overflow gates which channel water into four spillways.〔 The spillways incorporate side piers on the upstream face to more correctly channel water over the dam so that each spillway discharges the same amount of water.〔Șentürk, Fuat. ''Hydraulics of Dams and Reservoirs.'' Highlands Ranch, Colo.: Water Resources Publications, 1994, p. 37.〕 The spillways release their water slightly above the actual bed of the river,〔 creating a waterfall effect when they are fully open. A spillway tunnel carved from granite in the right bank of the river augments the spillways and provides for additional overflow.〔 The total spillway capacity is half that of Grand Coulee Dam in the United States.〔 The Export-Import Bank of the United States provided $8.9 million (about $67.2 million in 2010 inflation-adjusted dollars) in credits in 1958 to Iberduero to enable it to purchase six 120 Megawatt (MW) turbines and other electrical equipment for the power generating station, all of which were supplied by American firms.〔Export-Import Bank of the United States. ''Export-Import Bank of the United States Annual Report.'' Washington, D.C.: Export-Import Bank of the United States, 1959, p. 21.〕 The dam won Spain an international reputation as a builder of very large dams.〔"Spain." ''The New York Times.'' October 25, 1965.〕 The dam's eye-catching, "ski jump" style spillways are its most noted feature, and have been called "outstanding" by leading dam engineers.〔Thomas, Henry H. ''The Engineering of Large Dams.'' London: Wiley, 1976, p. 502.〕 The canyon through which the Douro River flows is exceptionally deep and narrow, resulting in a reservoir that has a relatively small surface area for its immense size. In some ways, this limits use of the reservoir for recreational activities. However, the Aldeadávila Dam reservoir is a popular one for boating.〔Lipscomb, Kelly. ''Adventure Guide: Spain.'' Edison, N.J.: Hunter, 2005, p. 156.〕 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「Aldeadávila Dam」の詳細全文を読む スポンサード リンク
|