东南大学学报（自然科学版）2025，Vol.55Issue(4)：1017-1026,10.DOI:10.3969/j.issn.1001-0505.2025.04.010
富水砂质粉土地层深基坑止水帷幕渗漏变形破坏分析
Analysis of leakage and deformation damage on waterproof curtains during deep excavation in water-rich sandy silt layers
摘要
Abstract
The rail transit develops fast with urbanization,resulting in a gradual increase in the deep founda-tion pit projects.Meanwhile,the groundwater problems associated with foundation excavation become more complex.Especially,in the weak strata rich in groundwater,the waterproof curtain is prone to leakage under the hydraulic pressure,leading to infiltration deformation and damage in the process of foundation pit dewater-ing and excavation.This research is based on the deep foundation pit project of Tianjin Metro Line 7 in water-rich sandy silt ground layer.The methods of fielding tests and finite element analysis are used together to investigate the seepage field and displacement field in the process of dewatering and excavation retained by the underground diaphragm wall(referred to as diaphragm wall,which is also used as the waterproof curtain).The leakage mechanism of the waterproof curtain is discussed.The methods and measures are suggested to pre-vent the leakage damage of waterproof curtain in the water-rich sandy silt ground layer.The results show that the ground settlement curve behind the wall caused by foundation pit excavation shows a"spoon-shaped"pro-file,primarily caused by soil unloading and consolidation;the deep horizontal displacement of the protective structure presents a"bow-shaped"curve,with the maximum displacement point gradually shifting downward as the excavation depth increases.Leakage of the underground diaphragm wall significantly increases founda-tion pit deformation,especially when leakage occurs at the corners of the pit;as the leakage area grows,both the seepage and displacement fields continue to evolve,although the rate of increase gradually decreases.In the design of foundation pit support,it is crucial to focus on the parameters of the underground diaphragm wall,monitor wall construction quality,and detect signs of leakage during the excavation process,taking timely preventive measures to reduce the risk of seepage damage in the foundation pit.关键词
基坑降水与开挖/地连墙渗漏/渗流场/位移场/变形破坏Key words
pit dewatering and excavation/leakage of underground diaphragm wall/seepage field/displace-ment field/deformation damage分类
建筑与水利引用本文复制引用
丁建文,任铁轮,高鹏举,焦雪洋,焦宁,刘雪源..富水砂质粉土地层深基坑止水帷幕渗漏变形破坏分析[J].东南大学学报（自然科学版）,2025,55(4):1017-1026,10.基金项目
国家自然科学基金资助项目(52378330) （52378330）
中建八局轨道交通建设有限公司科研资助项目(TJ-7-2022-QT-01). （TJ-7-2022-QT-01）
