The results from both the field measurements and numerical simulation were reported to comprehensively analyze the sediment siltation in the upper reach of the Deepwater Navigation Channel Project in the Yangtze Estuary after the project has been implemented. In this research, firstly some basic information about the river evolution in the Yangtze Estuary is analyzed, including the variations of water depths in the Hengsha Passage and the inlet cross-sections of the North Passage and the South Passage, and changes of diversion ratios of ebb flow and sediment flux in the North Passage and the South Passage. Then the Delft3D-Flow model is applied to simulate the hydrodynamics and sediment transport in the Yangtze Estuary. This model has been calibrated and the simulated results agree well with the measured data of the tidal levels, flow velocities and suspended sediment concentration (Ssc), indicating that the model can well simulate the hydrodynamics and sediment transport of the Yangtze Estuary caused by the Deepwater Navigation Channel Project. The research results show that the development of the Hengsha Passage and decrease of diversion ratio of ebb flow and sediment flux in the North Passage are the main reasons of sediment siltation in the upper reach of the Deepwater Navigation Channel in the Yangtze Estuary.

中文翻译：

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长江口深水航道上游泥沙淤积综合分析

据报道，通过实地测量和数值模拟的结果，可以对长江口深水航道工程实施后的泥沙淤积进行综合分析。在这项研究中，首先分析了有关长江口河道演变的一些基本信息，包括横沙河段水深的变化以及北河道和南河道的进口断面，以及分流比的变化。北通道和南通道的水流和泥沙通量减少。然后，使用Delft3D-Flow模型模拟长江口的水动力和泥沙输送。该模型已经过校准，模拟结果与潮汐测得的数据非常吻合，流速和悬浮泥沙浓度（Ssc），表明该模型可以很好地模拟深水航道工程引起的长江口水动力和泥沙输送。研究结果表明，横河通道的发展以及北通道的退潮和泥沙通量的分流比降低是长江口深水航道上游泥沙淤积的主要原因。