ACCRETION OF BEACH SAND BEHIND A DETACHED BREAKWATER.

Abstract

The problem of sand transport by a longshore current is clarified by observing the effect of a breakwater on this current. Sand samples were collected on a network from the beaches in the vicinity of the breakwater at Santa Monica, California. The distribution of median grain sizes is evidence for a reduction of the competence of the longshore current. The history of shore line changes discloses an accompanying reduction in the capacity of the current. A decrease in transporting power of the longshore current is correlated with a decrease in Q, the littoral drift factor, so that Q can probably be used as a qualitative measure of the sand transporting power of longshore currents. The history of accretion indicates that a shore line changes position in a direction toward equilibrium with respect to the forces acting on a beach. Given enough time, it is probable that the breakwater will become connected to the mainland.

Document Details

Document Type
Technical Report
Publication Date
May 01, 1950
Accession Number
AD0699394

Entities

People

  • John C. Ludwick
  • John W. Handin

Organizations

  • United States Army Corps of Engineers

Tags

Communities of Interest

  • Energy and Power Technologies

DTIC Thesaurus Topics

  • Beaches
  • Breakwaters
  • California
  • Coastal Regions
  • Grain Size
  • Landforms
  • Littoral Drift
  • Regions
  • Shores
  • Transport Ships

Readers

  • Coastal and Marine Engineering/Sediment Transport/Hydraulic Engineering
  • Systems Analysis and Design