A. Owczarczyk1, Z. Pruszak2, R. Wierzchnicki1
1 Institute of Nuclear Chemistry and Technology, 16 Dorodna Str., 03-195 Warsaw, Poland,
2 Institute of Hydroengineering, Polish Academy of Science, 7 Koscierska Str., 80-953 Gdansk, Poland
Interest and practical engineering activity is most often focused on the region of the coastal zone from the shoreline to a depth of the order of several meters. Sediment transport in this region was the object of intensive and complex field studies by the use of radioisotope tracers.
The survey was carried out in a multi-bar (4-5 bars) coastal zone 700 m long and about 1000 m wide. A 192Ir was used as a tracer, being component of specially prepared glass grains of the diameter of 0.020-0.025 cm and density of 2668 kg/m3.
Some basic sediment movement characteristics were studied, such as follows:
- critical velocites of single grains motion and mass transport beginning,
- local velocities of sediment,
- bed-load layer thickness,
- local bed-load sediment transport.
The basic meteorological and hydraulic parameters were recorded during the experiment run. The wave (amplitude and period) wind and current (direction and velocity) were continuously measured.
The total sediment transport rate in longshore direction in the area under test was estimate to 3-7 · 10-3m3/s. This range is typical for the intensive wave coming to the shore from direction of 10-30°.