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Accession Number
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PB2012-114455
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Title
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Evaluation of Bridge Scour Research. Research Results Digest 378.
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Publication Date
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Aug 2012
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Media Count
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27p
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Personal Author
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N/A
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Abstract
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The United States Geological Survey (USGS) defines scour as the hole left behind when sediment (sand and rock) is washed away from the bottom of a river. Although scour may occur at any time, scour action is especially strong during floods. Swiftly flowing water has more energy than calm water to lift and carry sediment down river. Scour affecting bridges may be classified as follows: Local scour is the removal of sediment from around bridge piers or abutments; Contraction scour is the removal of sediment from the bottom and sides of a river channel at the bridge opening. It is caused by the increase in the velocity of water as it moves through a bridge opening that is narrower than the river channel. The most common cause of this type of scour is contraction of the flow by bridge approach embankments encroaching onto the floodplain, into the main channel, or both; and Degradational scour is the general removal of sediment from the river bottom by the flow of the river that, while a natural process, may cause removal of large amounts of sediment over time at the bridge site. The obvious danger of scour at or near a bridge is that the scour will undermine the piers and abutments that support the bridge and cause its catastrophic failure.
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Keywords
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Bridge maintenance Bridges Examinations Highway bridges Monitoring Research projects Scour Scour damage Sediments
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Source Agency
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National Academy of Science Transportation Research Board
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NTIS Subject Category
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50A - Highway Engineering 50B - Civil Engineering 50C - Construction Equipment, Materials, & Supplies
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Corporate Author
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Transportation Research Board, Washington, DC. National Cooperative Highway Research Program.
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Document Type
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Technical report
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Title Note
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N/A
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NTIS Issue Number
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1225
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Contract Number
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N/A
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