针对南渡江水文、潮汐、地质等工程特点以及文明东越江隧道项目特点,对围堰分段、分期、高程设计、隧道埋深方案设计的关键技术进行分析,并结合防洪评价、工期、造价等因素对围堰设计、基坑设计等方案进行比选。研究结果表明: 1)合理确定围堰平面布置方案和施工工期是该方案成败的关键; 2)采用两边放坡的大开挖方案,结构内力、变形、沉降较双排桩显著降低,围堰结构更加安全,并能大幅缩短工期、节约工程造价。

Based on the hydrological, tidal, and geological characteristics of the Nandu River and the characteristics of the Wenming East Road Tunnel project, the key design technologies of section, stage and elevation of cofferdam and depth of tunnel are analyzed. The design schemes of cofferdam and foundation pit are compared in terms of flood control evaluation, construction period and cost. The study shows that: (1) The rational determination of cofferdam layout scheme and construction period is the key to the success of the project. (2) Compared to double-row pile, the structural internal force, deformation and settlement by adopting the large excavation scheme with both sides of the slope are much smaller, and the cofferdam structure is safer, which can greatly shorten the construction period and save the project cost.