长江下游镇扬河段河道演变及整治研究

Channel Evolution and Regulation of Zhenjiang-Yangzhou Reach of the Lower Yangtze River

长江镇扬河段是长江下游变化最剧烈的河段之一,近百年来其河道变化主要表现在世业洲洲头的不断崩退、左汊的缓慢发展及汇流后的主流不断右移,六圩弯道凹凸岸互换后的凹岸持续崩坍及弯道向下游不断的发展,和畅洲汊道由多汊演变为鹅头型双汊河道后发生主、支汊易位及左汊的持续发展等。其演变过程颇为复杂,河道整治难度较大。通过分析镇扬河段的河势特点及近百年来河道的演变特点,结合已实施的整治工程,分析了该河段工程的整治效果,总结了工程的整治经验,并且针对目前河段存在的主要问题提出了整治建议。

The Zhenjiang-Yangzhou reach（hereafter referred to as Z-Y reach） is one of the river sections with the most severe changes in lower Yangtze River.The evolution of this reach is complicated and the river regulation involves great difficulty.Changes of the river in the past century are described as follows： the head of Shiye sandbar collapsed continually and the left branch developed slowly with the mainstream moving towards the right after the confluence.The concave bank of Liuyu bend,which developed towards the downstream afterwards,collapsed constantly since the concave bank and convex bank exchanged.The multi-braided channel at Hechang island developed into a goose-head shaped double-braided channel,and afterwards the main channel exchanged with the branch channel while the left branch developed steadily.The effects of regulation works in this reach is analyzed,and regulation ideas are proposed for the existing problems.