龙口湾冲淤特性对人工岛群建设的响应

RESPONSE OF EROSION-DEPOSITION PATTERN TO ARTIFICIAL ISLANDS CONSTRUCTION IN LONGKOU BAY

龙口市拟建的离岸人工岛群可能将引起龙口湾内冲淤特性的变化及岸线的动态调整。运用MIKE21数学模型模拟了人工岛群建设前后海域潮流场和海底冲淤的变化特征,运用CERC公式计算了龙口湾沿岸输沙率的变化状况,并在以上基础上,分析了龙口湾冲淤特性对人工岛群建设的响应。结果表明,人工岛群建成后,其北侧和西南侧海域以淤积为主,西侧海域以冲刷为主;人工水道内部在西南向大风情况下淤积较为严重;界河口两侧沿岸输沙率差别较大,由界河口来沙和沿岸输沙引起的岛陆间水道的淤积速率约为12.5 cm/a。

The construction of offshore artificial islands under planning may cause change in erosion-deposition pattern and the dynamic adjustment of the coastline in the Longkou Bay.In this paper,we simulated the tidal current and erosion-deposition pattern for time before and after the construction of artificial islands with the MIKE21 Mathematical Model,calculated the variation of alongshore sediment discharge rates using CERC formula,and finally analyzed the response of erosion-deposition pattern to artificial islands construction in the Longkou Bay.The results show that after construction of artificial islands,deposition will increase in the northern and southwestern sea area while erosion will increase in the western sea area;severe deposition will be produced in artificial waterways under the southwestern wind;There exists big differences of alongshore sediment discharge rates in both sides of the Jie Estuary,the deposition rate in the waterway between islands and land caused by sediment from the Jie River and alongshore sediment discharge is about 12.5 centimeters per year.