DREDGING EFFECTS OF WATER-JET AND TEETH WITH THE DRAG HEAD

Dredging by trailing suction dredger for hard packed sand causes a remarkable decrease of the solid concentration and dredging efficiency. Field tests using the trailing suction dredger equipped with water-jet and teeth on its drag head were conducted and the effects of this auxiliary equipment were investigated. The water-jet extremely effective as far as the increase of the solid concentration is concerned, especially for the hard packed sand. For comparatively soft packed sand, however, the positive effects of the jet cannot be concluded in an unqualified manner in the aspect of power consumption. The effects of teeth strongly depend on shape and arrangement. It is desirable to weld teeth only on the heel part because teeth welded to the whole surface of a grate brings about the reverse effect. Furthermore, it is shown that the peak of the solid concentration exists around a ship's speed of 3 to 4 knots.

  • Supplemental Notes:
    • Paper F-4 from BHRA Fluid Engineering Symposium, University of Kent, Canterbury, England.
  • Corporate Authors:

    British Hydromechanics Research Association

    Cranfield MK43 0AJ, Bedfordshire,   England 
  • Authors:
    • YAGI, T
    • Okayama, Y
  • Publication Date: 1975-9

Subject/Index Terms

  • TRT Terms: Dredging
  • Subject Areas: Marine Transportation; Terminals and Facilities;

Filing Info

  • Accession Number: 00128424
  • Record Type: Publication
  • Source Agency: British Hydrodynamics Research Association
  • Files: TRIS
  • Created Date: Jan 14 1976 12:00AM