Liquefaction of Loosely Deposited Sandbed behind a Breakwater due to Wave Overtopping

This paper describes how, in the Port of Kushiro, a breakwater with an artificial shallow reef is being installed. This shallow reef will be used for fish and seaweed firm. The reef is filled with loosely deposited dredged sand and covered with armor blocks to prevent scouring by overtopping waves. Because of the strong wave overtopping, the sandbed will be suffered from liquefaction. Previous research conducted a series of experiments in order to examine wave-induced liquefaction in loosely packed fine sandbed. Liquefaction with residual pore pressure occurs because of wave drive shear stress in the sand bed. The compaction of a liquefied sandbed in response to cyclic wave loading was also observed. In a usual seabed, liquefaction with residual pore pressure does not occur because cyclic wave loads compact the sand. On the other hand, the loosely deposited sandbed behind the breakwater is likely liquefied due to wave overtopping after the construction. In order to avoid devastating liquefaction, this paper conducted a series of experiments in a wave flume. FEM simulation was also conducted in order to evaluate the liquefaction limit.

Language

  • English

Media Info

  • Media Type: Print
  • Features: Figures; References;
  • Pagination: pp 656-662
  • Monograph Title: Coastal Structures 2003

Subject/Index Terms

Filing Info

  • Accession Number: 01004078
  • Record Type: Publication
  • ISBN: 0784407339
  • Files: TRIS
  • Created Date: Sep 1 2005 10:54AM