盾构始发软土深基坑的变形及加固  

Deformation and reinforcement effects of soft soil deep foundation pits for shield tunnel launching

作　　者：诸葛绪松 周进威 祁文睿 李东洋 李强[3,6] 苏栋[3,6] ZHUGE Xusong;ZHOU Jinwei;QI Wenrui;LI Dongyang;LI Qiang;SU Dong(Zhuhai Dahengqin City New Center Development Co.Ltd.,Zhuhai 519030,Guangdong Province,P.R.China;Zhuhai Dahengqin Group Co.Ltd.,Zhuhai 519030,Guangdong Province,P.R.China;College of Civil and Transportation Engineering,Shenzhen University,Shenzhen 518060,Guangdong Province,P.R.China;China Railway 15 Bureau Group Co.Ltd.,Shanghai 201306,P.R.China;Zhuhai Institute of Urban Planning&Design,Zhuhai 519001,Guangdong Province,P.R.China;Key Laboratory for Coastal Urban Resilient Infrastructures,Ministry of Education,Shenzhen 518060,Guangdong Province,P.R.China)

机构地区：[1]珠海大横琴城市新中心发展有限公司,广东珠海519030 [2]珠海大横琴集团有限公司,广东珠海519030 [3]深圳大学土木与交通工程学院,广东深圳518060 [4]中铁十五局集团有限公司,上海201306 [5]珠海市规划设计研究院,广东珠海519001 [6]滨海城市韧性基础设施教育部重点实验室,广东深圳518060

出　　处：《深圳大学学报（理工版）》2024年第3期387-394,共8页Journal of Shenzhen University(Science and Engineering)

基　　金：深圳市高等院校稳定支持资助项目(20220810151354002);中铁十五局科研资助项目(CR15CG-ZH-HQMZSD-2021-00001(KJ));国家自然科学基金资助项目(51938008)。

摘　　要：软土地层具有高灵敏度、高压缩性和承载能力低的特点,在外荷载和震动的作用下容易产生变形和不均匀沉降.依托珠海市杧洲隧道工作井基坑工程,通过现场监测和数值模拟分析地下连续墙墙体水平位移、地表沉降和支撑轴力,研究软土深基坑开挖变形发展规律及被动区加固的影响.结果表明,墙体水平位移曲线图呈现“勺型”,最大值出现在1.4倍基坑开挖深度左右的位置,被动区加固使墙体水平位移最大值降低33%;地表沉降呈现“沉降槽”曲线特征,最大值出现在距离基坑边缘0.3倍开挖深度的位置,被动区加固使地表沉降最大值小于开挖深度的0.1%;开挖土体使支撑轴力迅速增大,下一层支撑的设置可以有效降低上一道支撑的轴力增长,被动区加固使支撑轴力最大值降低25%;被动区加固是软土深基坑控制变形的有效措施.研究结果可为软土深基坑施工和监测提供参考.Soft soil layers are characterized by high sensitivity,high compressibility,and low bearing capacity,making them prone to deformation and uneven settlement under external loads and vibrations.Based on the foundation pit project of the Mangzhou Tunnel in Zhuhai City,this study combines field monitoring and numerical simulation to analyze the horizontal displacement of diaphragm walls,surface settlement,and axial forces of lateral supports.The study aims to investigate the deformation development pattern of deep excavations in soft soil and the impact of passive zone reinforcement.The results show that the curve of the wall horizontal displacement exhibits a"spoon-shaped"pattern,with the maximum value occurring at around 1.4 times the excavation depth of the pit;passive zone reinforcement reduces the maximum value of wall horizontal displacement by 33%.The surface settlement follows a"settlement trough"curve,with the maximum value occurring at a distance of 0.3 times the excavation depth from the edge of the pit,and passive zone reinforcement limits the maximum surface settlement to less than 0.1%of the excavation depth.Excavation of the soil rapidly increases the axial force of current support,but the installation of next layer support effectively reduces the growth rate of axial force of the previous support,and passive zone reinforcement reduces the maximum support axial force by 25%.It is proved that passive zone reinforcement is an effective measure for controlling deformation of deep excavations in soft soil.The findings of this study can provide valuable references for the construction and monitoring of deep excavations in soft soil.

关 键 词：岩土工程 深基坑 变形控制 被动区加固 数值模拟 基坑监测 

分 类 号：TU44[建筑科学—岩土工程]