杭州湾南岸电厂取水口海区泥沙冲淤分析

Analysis of sediment scouring and silting in water intake area of south bank power plant in Hangzhou Bay

杭州湾南岸电厂取水口所在海床的冲淤情势是取水口高程设置和电厂安全运行需要考虑的核心要素。基于工程海区不同历史时期的地形资料,结合水沙运动规律、人类活动和二维潮流泥沙数学模型计算,分析了工程海区海床演变规律和趋势。结果表明:工程所在海床属于杭州湾南岸滩涂的一部分,摒弃围垦引起的短期冲刷效应,海床长期处于缓慢淤涨态势,淤积速率约0.04 m/a;沿岸潮流的输沙作用以及围填海等人类活动是海床淤涨的主因。工程建设后,取水口区域仍将保持淤积态势,周边规划工程亦将使取水口床面区域产生0.2 m左右的淤积。研究成果可为取水口方案的确定提供理论依据和数据支撑。

The scouring and silting in marine area of water intake is the core factor for level design of water intake of a power plant,on south bank in Hangzhou Bay.On the basis of topographical data in different historical periods,and by considering the law of water and sediment movement,human activities,we analyzed the law and trend of seabed evolution by 2D flow and sediment mathematical model.The results showed that the seabed is part of the south bank shoal;the seabed is in slow siltation chronically regardless of short-term scour effect caused by reclamation,at a deposition rate of around 0.04 meters per year.Seabed siltation is caused by sediment transportation of coastal current and human activities such as sea reclamation.After construction,seabed of water intake area is still in siltation,and the projects to be constructed in nearby area also contribute to siltation of 0.2 meters.