填海工程建设前后丹东港海域泥沙冲淤变化特征与成因分析

利用近年来水深地形数据和2010年全潮水文观测资料分析了丹东港海域在填海工程建设前后的冲淤变化特征,并阐述了冲淤变化的成因,以对该类型海域海洋工程的选址和海洋环境保护等提供科学依据。研究结果表明,研究区海底在工程建设前除靠近大东作业区的岬角处冲刷较大外,其他海域整体冲淤厚度小于0.2 m/a。工程建设后海底冲淤格局发生重新分布,主要表现在工程南侧普遍冲刷和东侧航道内及西南侧海域的淤积。利用刘家驹公式计算了工程建设前后的航道回淤强度,计算结果表明:工程后A点年均淤积厚度减小了0.09 m,B、C点年均淤积厚度分别增加了0.02、0.19 m。Mike21数值模拟结果显示,工程建设改变了原来的流场,造成研究区冲刷悬浮的泥沙在潮流的作用下重新搬运与沉积,同时波浪场也因工程的影响下蚀海底的能力增强。

Sediment scouring and deposition at the Dandong Port before and after the construction of reclamation project

We studied the sediment scouring and deposition at the Dandong Port before and after reclamation based on underwater topographic data and fixed-point marine hydrological observations in 2010. The data suggest strong erosion in the headland of the Dadong area. The rate of sediment scouring and silting was less than 0.2 m/a. After reclamation, the patterns of sediment scouring and deposition were redistributed. There was erosion south of reclamation and deposition east and southwest of the reclamation. The channel silting before and after reclamation was calculated at 0.09 m at point A, and at points B and C increased by 0.02 m to 0.19 m. Numerical simulations suggest that there was redistribution and erosion of sediments after the reclamation because of the increased the wave energy.