낙동강 하구역과 신항만 연결잔교부의 물질수송예측

Abstract

The pier bridge in Busan New-port was a channel of transport for sea water between two sea areas. This study analyzes the characteristics of material transportation between Busan new-port and Nakdong river estuary. Therefore current meter(Compact-EM) was established on a pier bridge and current velocity is analyzed for flow direction. Measurements of water temperate, salinity, turbidity, and tide is also analyzed to determine the characteristics of sea water and described the tidal current between Busan New-port and Nakdong river estuary. For the purpose of indicating characteristics of tidal current numerical modeling is used. From the result of measuring the component of tidal current velocity on the pier bridge, it is determined that the dominant outflow direction in ebb tidal current was from the Nakdong river estuary to Busan New-port. However, in flood tidal current the dominant direction was from the Busan New-port to Nakdong river estuary. Maximum speed of current was about 13.18 cm/sec during the 1st field measurement and 2nd field measurement maximum speed of current was 30.80 cm/sec. Total volume transport of sea water calculations revealed 184.71 m3/sec and residual volume transport was (+)59.74 m3/sec during the 1st field measurement. 2nd field measurement total volume transport was 331.15 m3/sec and residual volume transport was (-)28.88 m3/sec. In the case of high water level and low water level, the results of field measurement were show that salinity and water temperature became stratification. Under circumstance of the flood tide, salinity is increased and turbidity is decreased. On the other hand, when the ebb, salinity is decreased and turbidity is increased. The numerical simulation for three different topography cases are calculated. The results are summarized as follows: 1) The volume of material transportation about 0.7～18.4% is decreased as the depth of Busan new-port decrease (10 m). 2) The volume of material transportation about 3.5～21.9% is increased as channel constructed to the Nakdong river estuary direction.