河口整治工程的实施效果与堤坝的结构型式密切相关,在河工模型上直接研究局部复杂结构对整治效果的影响有较大难度.以长江口深水航道治理二期工程北导堤NⅡC区段空心方块斜坡堤结构为个例,采用水槽试验和动床模型相结合方法,通过水槽试验确定可以在特定河工模型上使用的概化透水结构,使在模型上精确模拟局部复杂结构对整治效果的影响成为可能.研究成果认为,二期工程NⅡC区段2 600 m导堤不建对北槽出口段的整治效果有明显影响,NⅡC区段导堤高程降低1 m或采用空心方块斜坡堤透水结构对整治效果影响不大.
Effects of estuary regulation are related to the structural type of dykes, but it is difficult to study the effect of some local complex structures with physical models directly. Taking NII C segment of the 2nd-Phase Project of the Deep Water Channel Project at the Yangtze Estuary as a case, in the paper the method of research on engineering effects of hollow-block structures is discussed. By comparison of different schemes, it is found that the scheme without 2 600 m-long training dike of NII C segment does harm to the existing channel of North Passage, and that there is little influence when the height of 2 600 m-long training dike of NII C segment decreases by 1 m or when the scheme adops the hollow-block mound breakwater structure.