长江中游典型顺直分汊河段冲刷调整的特性与机理  

Characteristics and mechanism of scouring adjustment in typical straight braided channel of the Middle Yangtze River

作　　者：陈立[1] 崔超 袁晶 何小花 CHEN Li;CUI Chao;YUAN Jing;HE Xiao-hua(State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China;Bureau of Hydrology,Changjiang Water Resources Commission,Wuhan 430010,China;Hubei Provincial Water Resources and Hydropower Planning Survey andDesign Institute,Wuhan 430064,China)

机构地区：[1]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072 [2]长江水利委员会水文局,湖北武汉430010 [3]湖北省水利水电规划勘测设计院,湖北武汉430064

出　　处：《泥沙研究》2023年第1期1-7,共7页Journal of Sediment Research

基　　金：国家重点研发计划项目(2016YFC0402101)。

摘　　要：与单一分汊河段相比,连续分汊河段的上游和下游汊道段相互影响,主支汊冲刷调整更加复杂。基于实测资料分析了长江中游武汉河段白沙洲-潜洲连续顺直分汊段冲刷调整的特性与机理。分析结果表明:三峡水库蓄水后两汊道河段的主支汊深泓纵剖面均冲刷下降,断面向窄深发展,江心洲的洲体冲刷萎缩;白沙洲主汊冲刷快于支汊。潜洲支汊冲刷快于主汊,支汊分流比增加。两汊道段的相关性导致白沙洲主汊深泓的右摆增强了潜洲支汊的分流比和冲刷动力,减小了潜洲主汊的分流比和冲刷动力,同时潜洲支汊河床的抗冲性弱于主汊,白沙洲主汊的抗冲性弱于支汊,两方面因素共同导致了两汊道段主支汊不同的冲刷发展过程。The upstream and downstream braid reaches of continuous braided channel affect each other, and the scour adjustment of the main-minor branch is more complex. Based on observed data, the scour adjustment of Baishazhou-Qianzhou continuous straight braid channel in Wuhan Reach of the middle Yangtze River and the mechanism are analyzed. Results show that the thalweg of the major-minor branch of the two branch sections has been cut down after impoundment, the channel section has been brushed to deep and narrow, and the size of beach reduced due to scour. the scour of the main branch of Baishazhou braid channel is faster than that of the minor branch, and the domain position of the main branch has been strengthened;the scour of minor branch Qianzhou braid channel is faster than that of main branch, and the minor branch develops. The relevance between the two channels makes the right swing of the thalweg of the main branch of Baishazhou enhance the diversion ratio and scour power of the minor branch of Qianzhou braided channel, and reduce the diversion ratio and scour power of the main branch of Qianzhou braid channel. Besides, the riverbed scour resistance of the minor branch of Qianzhou is weaker than that of the main branch, and the riverbed scour resistance of the main branch of Baishazhou is weaker than that of the minor branch. Two factors lead to the development of differential scouring in the main-minor branch of the two channels.

关 键 词：长江中游 武汉河段 连续顺直分汊段 主支汊 冲刷调整 

分 类 号：TV147.1[水利工程—水力学及河流动力学]