长江口深水航道治理一期工程实施后北槽冲淤分析

对长江口深水航道治理一期工程实施后北槽的地形资料进行分析计算 ,论述了北槽河床冲淤变化。结果表明 :一期工程实施后 ,整治工程段北槽河床普遍冲刷 ,平均水深增幅达 1 2m ,断面平均水深最大增幅超过2m ,坝田明显淤积 ,河床断面比较对称 ,航槽回淤减少。北槽进口段和北槽中段的深槽发生较为明显的淤积 ,北槽纵向河床断面面积和平均水深趋于均匀 ,形成了一条上、下段平顺衔接的微弯深泓线。工程实施后北槽的河床总容积基本保持不变。整治建筑物完成一年后河床基本达到冲淤平衡 ,工程引起河床大幅度冲淤调整完成后 ,北槽仍具有明显的洪淤枯冲规律 ,主槽季节性冲淤幅度平均在 30cm～ 5 0cm之间。

Erosion-deposition analyses on the north passage after implementing the first stage project of the Yangtze estuary deepwater channel regulation

According to topographical map of the north passage after the first-phase project of the Yangtze Estuary Deepwater Channel Regulation,erosion-deposition of the north passage are studied by using the digital elevation model (DEM). After the first-phase project being built, the river bed of the north passage was universally deepened, the average and mximum depths of cross-section respectively increase 1.2m and 2m, the dam field gets an obvious deposition, the cross section of the river bed becomes much more symmetrical, and the amount of deposited sediment in waterway channel greatly reduces. One year later after the 1st stage regulation project of the Yangtze Estuary Deepwater Channel, erosion and deposition in the north passage achieves approximate equilibrium and exhibits deposition in the flood season and erosion during the low river runoff. The thickness of erosion and deposition ranges from 30cm to 50cm.