长江口南沙头通道限流潜堤局部冲刷原因及对策分析  

Analysis of causes and treatments of the local scours near the submerged dike in Nanshatou passage of the Yangtze estuary

作　　者：苏涛 石进 陈琳 SU Tao;SHI Jin;CHEN Lin(Shanghai Waterway Engineering Design and Consulting Co., Ltd., Shanghai 200120, China;Yangtze Estuary Waterway Administration Bereau, MOT, Shanghai 200017, China)

机构地区：[1]中交上海航道勘察设计研究院有限公司,上海200120 [2]交通运输部长江口航道管理局,上海200017

出　　处：《海洋工程》2020年第4期46-53,60,共9页The Ocean Engineering

基　　金：国家重点研发计划项目(2017YFC0405400)。

摘　　要：长江口南北港分汊口河段新浏河沙护滩潜堤及南沙头通道潜堤工程是典型的航道整治工程,经调查发现限流潜堤冲刷坑在两侧余排外对称分布,12 m以深等深线呈不连续坑状,南侧个别区段冲刷坑已侵入排内。基于工程地形监测和地质资料分析,通过现场水深测量、旁扫声纳扫测、潜水探摸、水文观测和三维潮流数学模型计算等手段,对限流潜堤排外局部冲刷情况和发生原因进行研究。研究结果表明潜堤排外冲刷是越顶水流长期作用所致,冲刷发展变化具有代表性,冲刷最大深度与地质条件有一定相关性。潜堤南侧护底余排边缘局部余排受外力损毁,引起排内冲刷,如进一步发展会影响堤身及结构安全,需对护底损坏部位进行修复以保证整治建筑物护底功能正常发挥。The pierhead of Xinliuhesha and the submerged dike of Nanshatou passage project in the south and northes branches of the Yangtze River estuary are typical channel regulation projects.The scour pits near the current-limiting submerged dike are symmetrically distributed outside the bed protection mattress on both sides,and breaking the 12m isobaths nearby.Some scour pits on the south side of the regulation buildings have enlarged and invaded into the range of soft mattress.The study of the local scour condition and scour reason of the flow-limiting submerged dike section can accumulate experience for similar projects.Based on the comprehensive analysis of monitoring data by use of bathymetry and side scan sonar,by means of hydrological observation,diving exploration,river regime analysis and three-dimensional tidal current mathematical model calculation,the causes of local scour outside the submerged breakwater with limited flow are analyzed.The result of our study shows that the local scours near submerged dikes are caused by the overtopping flow scouring in a long term,and the south edges of soft mattress have been damaged by external force.If the scour pit further develops,it will affect the building stability.So it is necessary to take remedial measures to ensure the normal function of the renovation building at the north-south passage bifurcation of the Yangtze estuary.This study has provided a good example for the local scour repairing near regulation structures in tidal estuaries.

关 键 词：长江口 南北港 航道整治 整治建筑物 潜堤 冲刷深度 局部冲刷修复 

分 类 号：U617.9[交通运输工程—船舶及航道工程]