퇴적물이동 3차원 모델링

Abstract

Numerical modeling and field experiment have been conducted to predict the sediment transport arising from undersea sand extraction in coastal waters of Korea. The macro-tidal Kyunggi Bay is approximately 20,000 km2, where underwater sand has been extracted in the amount of approximately more than 35 million m3 annually. Suspended sediment released by over-spilled water to the surface water and the sea bed disturbance due to the action of cutter-head during dredging operation are critically important issues on benthic biology and coastal erosion. In this study, we conduct numerical simulation using ROMS to investigate the fate of sediment dispersion released at the surface as well as in the bottom layer. Each source level of different sediment size groups has been quantified using field experiment data. The three dimensional hydrodynamic forcing associated with combined effect of wave and current in the bottom layer has been also considered. According to the intensity of sand extraction and hydrodynamic condition, the sediment dispersion in the water column and the deposition feature at seabed show reasonable replacement of new sediment size group, that seems very important to the habitat change for the benthic community