Results from a two-dimensional case study carried out at RHL showed that irregular waves seemed to represent a more severe wave attack than regular waves with heights equal to the significant wave heights of the irregular wave. It was further concluded that the factors that influence the stability of a breakwater are many and complex and vary within wide ranges from project to project. The best basis for breakwater design is still model testing, preferably with irregular waves. This conclusion was also positively underlined by van Oorschot. In view of these conclusions a case study has been carried out at RHL regarding the stability of the head of the rubble mound breakwater under construction at the fishing port of Sorvaer in the northernmost county Finnmark of Norway. The sponsor of the tests was the Norwegian State Harbour Works. The study involved evaluation of the design wave height from meteorological data as well as model testing. The evaluation of the design wave height followed more or less standard procedures, the presentation of which is of less general interest. The tests involved intensive investigations of the breakwater stability in regular waves as well as in irregular waves. It is the latter tests that are considered to be of most general interest and which are reported in this paper. The following conclusions were drawn from the tests results: 1. The stability of the armour layer seems to be the same in regular and irregular waves when the significant wave heights of the irregular wavetrain correspond to the height of the regular waves. 2. The two long terms indicated a breakdown for lower waves than in the other tests. However, since only two such tests were run, no definite conclusions can be drawn on this point. 3. Regarding erosion on the foot berm this seemed in some cases to be the same in regular and irregular waves. The tests indicated that the erosion was larger with irregular waves than with regular waves when the waveheights were just above the waveheight when erosion started. At larger waveheights the erosion tended to be approximately the same for regular and irregular waves. None of the tests showed damage to the armour layer due to erosion of the foot berm.

  • Supplemental Notes:
    • Abstract of paper delivered at the First International Conference on "Port and Ocean Engineering under Arctic Conditions" held at Trondheim, Norway, August 23-30, 1971
  • Corporate Authors:

    POAC Conference

  • Authors:
    • Bratteland, E
    • Torum, Alf
  • Publication Date: 1971-8-23

Subject/Index Terms

Filing Info

  • Accession Number: 00025692
  • Record Type: Publication
  • Source Agency: Arctic Institute of North America
  • Files: TRIS
  • Created Date: Mar 28 1972 12:00AM