A description is giving of a number of tests of general scour in a long contraction. For each test the upstream depth and discharge were varied but all tests were carried out with the same sand and contraction ratio. The results of the tests are compared with predictions from two equations. The closest agreement was obtained with an equation developed from the concept of critical bed shear stress. It is suggested that this equation is adequate for design purposes when multiplied by a safety factor of 1.2. In those tests where the ratio of scoured depth to upstream depth was greater than 1.5, a localised region of deep scour at the entrance to the contraction was noted. Although the tests were not sufficiently extensive to characterise this phenomenon, its relevance to design situations is discussed briefly. (Author)

  • Corporate Authors:

    National Roads Board, New Zealand

    P.O. Box 12-041
    Wellington,   New Zealand 
  • Authors:
    • KELLER, R J
  • Publication Date: 1979

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Filing Info

  • Accession Number: 00315367
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Dec 11 1980 12:00AM