长江口圆圆沙段12.5m航道淤积原因分析  

Study on the sediment deposition in Yuanyuansha reach of 12. 5m deepwater channel in Yangtze Estuary

作　　者：赵晓冬[1] 李肖肖[1] 罗小峰[1] 陈少明[1] 

机构地区：[1]南京水利科学研究院水文水资源与水利工程科学国家重点实验室,江苏南京210029

出　　处：《泥沙研究》2014年第6期63-67,共5页Journal of Sediment Research

基　　金：水利部公益性行业科研专项(201201070);交通运输部重大科技专项(201132874640)

摘　　要：长江口圆圆沙航道段位于深水航道治理分流口工程和横沙通道之间,航道长度15.44km,属未采取整治工程措施,仅通过疏浚开挖形成的人工航道。2010年12.5m深水航道开通以来航道疏浚量明显增大。通过近年来水文泥沙地形实测资料分析,从水动力条件、泥沙、河势与局部地形变化等因素讨论了圆圆沙航道回淤原因。结果表明圆圆沙段河槽自然水深不足10m,航道疏深后滩槽高差加大引起泥沙回淤增大;北槽实施减淤工程后圆圆沙段落潮流速和输沙能力减小;圆圆沙航道段处在涨、落潮分汇流河段,航道与底部水流方向存在交角等是航道淤积增加的主要因素。针对圆圆沙段航道回淤原因,从挡沙和强流两个方面提出了减淤办法。Yuanyuansha （YYS） deepwater channel in Yangtze Estuary,with a length of 15.44km, is located between the diversion-mouth of the deepwater channel regulation project and Hengsha Passage. This artificial channel is constructed and maintained by dredging without regulation project. However, the dredging volume has increased obviously after dredging of the 12.5m deepwater channel. By analyzing the series of hydrology, sediment and topography data observed in situ during recent years, the mechanism for sediment deposition in 12.5m YYS reach deepwater channel are studied based on hydrodynamic conditions, sediment deposition, riv- er regime conditions and local terrain changes. The elevation difference of the main channel and floodplains has increased after dredging to 12.5m in the YYS channel from the natural depth which is less than 10m; the velocities and sediment transport dynamics of the ebb flows has decreased after construction of the project of re- duce deposition in North Passage; crossing angle between the navigation channel and the direction of bottom current has existed because YYS channel is located in the distributary and confluence reach of ebb and flood tide. Those reasons are the main causes of deposition increase. Finally, methods are proposed to reduce depo- sition from resisting sediment and strengthening flow.

关 键 词：圆圆沙航道 淤积原因 长江口 

分 类 号：TV148[水利工程—水力学及河流动力学]