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Corresponding Author

梁荣柱，男，博士，副研究员.E-mail：[email protected]

Abstract

A deep foundation pit of Wuhan Metro Line 12 is located in the water-rich sand layer on the first terrace of the Yangtze River. The deep foundation pit is 176.8 m long and 29.0 m wide, with an excavation depth of 26.5 m in the standard section. It is supported by a diaphragm wall and five levels of internal bracing. Large areas of surcharge exist on both sides around the foundation pit, resulting in a high construction risk. To investigate the excavation deformation characteristics of the deep foundation pit, relying on field monitoring techniques, field monitoring and data analysis were conducted on the surface deformation around the foundation pit, the lateral deformation of the diaphragm wall, and the axial force of bracing during excavation. The results show that the maximum vertical deformation of surface around the foundation pit reaches 0.15% ‒0.17% of the excavation depth. Under the influence of foundation pit dewatering, the vertical surface deformation increases significantly after excavation enters the confined water-rich fine sand layer. The lateral deformation of the diaphragm wall increases with increasing excavation depth, and the wall deformation curve shows an “arch” profile. The maximum horizontal displacement gradually moves downward as the excavation depth increases. After excavation reaches the confined water-rich fine sand layer, the wall deformation increases significantly, with a maximum increase of 161%. The deformation of the retaining structure of the foundation pit exhibits a spatial effect, and the maximum difference in deformation between the long side and the short side reaches 55 mm. Surface surcharge further aggravates the lateral displacement of the foundation pit wall. The lateral water and earth pressure in the standard section of the supporting structure of the foundation pit is mainly borne by the second steel pipe brace, while that at the pit corners is mainly borne by the third and fourth reinforced concrete braces.

Publication Date

10-29-2026

DOI

10.14048/j.issn.1671-2579.2026.05.003

First Page

21

Last Page

31

Submission Date

October 2026

Reference

[1]Liu G B,Jiang R J,Ng C W W,et al.Deformation characteristics of a 38 m deep excavation in soft clay [J].Canadian Geotechnical Journal,2011,48(12):1817 -1828.

[2]胡安峰,张光建,王金昌,等.地铁换乘车站基坑围护结构变形监测与数值模拟 [J].岩土工程学报,2012,34(增刊1):77-81.Hu Anfeng,Zhang G uangjian,Wang Jinchang,et al.Monitoring and numerical simulation of deformation of retaining structure excavation of a metro transfer station[J].Chinese Journal of Geotechnical Engineering,2012,34(S1):77-81.

[3]Liu G B,Ng C W W,Wang Z W.Observed performance of a deep multistrutted excavation in Shanghai soft clays[J].Journal of Geotechnical and Geoenvironmental Engineering,2005,131(8):1004 -1013.

[4]宋建学,郑仪,王原嵩.基坑变形监测及预警技术 [J].岩土工程学报,2006,28(增刊 1):1889 -1891.Song Jianxue,Zheng Yi,Wang Yuansong.Deformation monitoring and alerting technology of foundation pits [J].Chinese Journal of Geotechnical Engineering,2006,28(S1):1889 -1891.

[5]贺振昭,杨新,叶超,等.地铁深基坑内支撑结构优化分析[J].安全与环境工程,2021,28(1):68-78.He Zhenzhao,Yang Xin,Ye Chao,et al.Optimization analysis of supporting structure in deep excavation of metro [J].Safety and Environmental Engineering,2021,28(1):68-78.

[6]Ou C Y,Hsieh P G,Chiou D C.Characteristics of ground surface settlement during excavation [J].Canadian Geotechnical Journal,1993,30(5):758-767.

[7]李镜培,陈浩华,李林,等.软土基坑开挖深度与空间效应实测研究 [J].中国公路学报,2018,31(2):208-217.Li Jingpei,Chen Haohua,Li Lin,et al.Observation on depth and spatial effects of deep excavation in soft clay [J].China Journal of Highway and Transport,2018,31(2):208-217.

[8]Long M.Database for retaining wall and ground movements due to deep excavations [J].Journal of Geotechnical and Geoenvironmental Engineering,2001,127(3):203-224.

[9]Finno R J,Bryson L S.Response of building adjacent to stiff excavation support system in soft clay [J].Journal of Performance of Constructed Facilities,2002,16(1):10-20.

[10]Likitlersuang S,Surarak C,Wanatowski D,et al.Finite element analysis of a deep excavation:A case study from the Bangkok MRT [J].Soils and Foundations,2013,53(5):756-773.

[11]Simpson B,Vardanega P J.Results of monitoring at the British library excavation [J].Proceedings of the Institution of Civil Engineers-Geotechnical Engineering,2014,167(2):99-116.

[12]Wang Z W,Ng C W,Liu G B.Characteristics of wall deflections and ground surface settlements in Shanghai [J].Canadian Geotechnical Journal,2005,42(5):1243 -1254.

[13]吴意谦,朱彦鹏.兰州市湿陷性黄土地区地铁车站深基坑变形规律监测与数值模拟研究 [J].岩土工程学报,2014,36(增刊 2):404-411.Wu Yiqian,Zhu Yanpeng.Monitoring and numerical simulation of deformation law of deep foundation pit of subway station in Lanzhou collapsi ble loess [J].Chinese Journal of Geotec hnical Engineering,2014,36(S2):404-411.

[14]彭斌,袁杰,张小勇,等.圆砾地层深基坑地下连续墙变形特性分析 [J].土木工程学报,2017,50(S1):65-69.Peng Bin,Yuan Jie,Zhang Xiaoyong,et al.Analysis on deformation of diaphragm wall in round gravel strata [J].China Civil Engineering Journal,2017,50(S1):65-69.

[15]高洪赟,徐天涵,王志华,等.深基坑开挖对自身围护结构及邻近隧道的影响研究 [J].中外公路,2025,45(2):29-37.Gao Hongyun,Xu Tianhan,Wang Zhihua,et al.Influence of deep foundation pit excavation on retaining structure and adjacent tunnels [J].Journal of China & Foreign Highway,2025,45(2):29-37.

[16]陈登伟.紧邻既有车站和钢便桥的超大异形基坑施工方案优化 [J].中外公路,2024,44(6):11-19.Chen Dengwei.Optimization of construction scheme of ultra-large special-shaped foundation pit adjacent to existing station and temporary steel bridge [J].Journal of China & Foreign Highway,2024,44(6):11-19.

[17]徐立武,陈卓异,邱力杰.钢换撑支撑体系下狭长形基坑围护结构受力及变形分析 [J].中外公路,2024,44(3):193-201.Xu Liwu,Chen Zhuoyi,Qiu Lijie.Stress and deformation of retaining structure in narrow and long foundation pit based on steel braces [J].Journal of China & Foreign Highway,2024,44(3):193-201.

[18]Zeng C F,Powrie W,Xu C J,et al.Wall movement during dewatering inside a diaphragm wall before soil excavation[J].Underground Space,2025,22:355-368.

[19]Yang K L,Xu C J,Zeng C F,et al.Analysis of recharge efficiency under barrier effects incurred by adjacent underground structures [J].Water,2025,17(2):257.

[20]Ye C,Li Z C,He Z Z,et al.Numerical investigation of retaining structure response to surrounding surface surcharge during deep excavation [J].Soil Mechanics and Foundation Engineering,2023,60(3):236-243.

[21]Clough G W,Smith E M.Movement control of excavation support system by iterative design [J].American Society of Civil Engineer,1989:869-884.

[22]Clough G W,O’Rourke T D.Construction induced movements of in-situ walls [C]//Design and Performance of Earth Retaining Structures.Geotechnical Special Publication,1990,25:439-470.

[23]Hsieh P G,Ou C Y.Shape of ground surface settlement profiles caused by excavation [J].Canadian Geotechnical Journal,1998,35(6):1004 -1017.

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