软土地区超大深基坑地下水防控技术研究

Research on Groundwater Prevention and Control Technology for Ultra-large Deep Foundation Pits in Soft Soil Areas

摘要:

依托上海市某开挖面积10.9万m²深基坑工程，综合研究城市区域软土地层超大型深基坑工程地下水防控技术。根据基坑水文地层条件、工程特征，梳理了超大深基坑地下水防控的重点和需求。在此基础上，考虑大型基坑安全成本和经济性的前提下，重点研究了大型深基坑分坑和降水井布置方法、围护结构安全防渗技术、坑内落深坑地下水处理技术以及基坑开挖降水工艺等内容。为软土地区超大型深基坑地下水防控提供了宝贵的案例分析。

Abstract:

This paper presents a comprehensive study on groundwater control technologies for an ultra-large deep excavation engineering in soft soil deposits of an urban area, based on a case study in Shanghai with an excavation area of 109,000 m2. The critical aspects and specific requirements for groundwater prevention and control in ultra-large deep excavation are identified through the analysis of the hydrogeological conditions and engineering characteristics of the site. With the consideration for both safety and cost-effectiveness in large deep excavation engineering, the research focuses on several key technologies: the methodology for partitioning the large deep excavation and arranging dewatering wells, anti-seepage techniques for the retaining structure, groundwater treatment for local deep excavation zone(Pit-in-Pit), and dewatering procedures during the excavation process. This study provides a valuable case analysis for groundwater control in ultra-large deep excavations in soft soil regions.