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The Assiut Barrage is a dam on the Nile River in the city of Assiut in Upper Egypt (250 miles to the south of Cairo). It was completed in 1903. ==Background== It was designed by the famous British engineer Sir William Willcocks who also concurrently designed and built the Aswan Low Dam, the first Nile reservoir, about up-stream. The Assiut dam was constructed between 1898 and 1903, and in conjunction with the reservoir, provided for the diversion of river water into Egypt's largest irrigation canal, the Ibrahimiya Canal, during the low water season. The dam was estimated to cost £525,000 but by the time of its completion it actually cost £870,000. The main contractor for the project was the British contractor John Aird & Co..〔(Egypt bond )〕 The project's massive size involved 2,400,000 cubic yards of earthwork, 125,000 cubic yards of concrete, 85,000 cubic yards of masonry, 125,000 cubic yards of pitching and more than 4,000 tons of cast iron pipes. The dam consists of a masonry dam about long extended on both sides by earthen banks, making a total length of about . There are 111 arched openings of span in the masonry dam. They can be closed by steel sluice-gates high. The piers and arches are founded upon a masonry platform wide by thick. This platform is protected on its up-stream and down-stream sides by a continuous and impermeable line of cast iron tongued and grooved sheet-piling with cemented joints. This piling extends into the sand bed of the river to a depth of below the upper surface of the platform and prevents it from being undermined. The river bed is protected against erosion for a width of upstream by a stone paving laid on a puddle clay blanket to check infiltration, and on the downstream side for the same width by a stone paving having an inverted filter bed underneath, so that any springs that may be caused by the water above the sluices shall not carry sand with them from beneath the paving. The piers between the openings have a length of up and down stream and are wide with the exception of every thirtieth pier, which has double this width. The roadway is above the top of the masonry platform. The dam has a maximum height of about , the maximum head of water retained being about . It is constructed of granite, the foundation platform mentioned above being of concrete. A lock long by wide and capable of passing the largest Nile cargo ships and barges was constructed at the dam.〔Edward Wegmann, (1918) ''The Design and Construction of Dams'', John Wiley & Sons, Inc., New York〕 The Ibrahimiya head regulator structure, which was built at the same time when the Assiut Barrage was being constructed, was of similar design to the barrage except having only nine 5 m wide sluices, and a 9 m wide lock. 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「Assiut Barrage」の詳細全文を読む スポンサード リンク
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