长江科学院院报 ›› 2020, Vol. 37 ›› Issue (11): 81-88.DOI: 10.11988/ckyyb.20190905

• 岩土工程 • 上一篇    下一篇

地下连续墙与止水帷幕共同作用下富水砂层深基坑变形性状

邱明明1, 杨果林2, 申权3, 段君义2, 张沛然2   

  1. 1.延安大学 建筑工程学院,陕西 延安 716000;
    2.中南大学 土木工程学院,长沙 410075;
    3.湖南工业大学 土木工程学院,湖南 株洲 412007
  • 收稿日期:2019-07-29 修回日期:2019-08-21 出版日期:2020-11-01 发布日期:2020-12-02
  • 通讯作者: 杨果林(1963-),男,湖南桃江人,教授,博士,博士生导师,主要从事岩土工程、道路与铁道工程方面的研究。E-mail:guoling@mail.csu.edu.cn
  • 作者简介:邱明明(1985-),男,陕西商洛人,讲师,博士,主要从事交通岩土工程、隧道及地下工程方面的研究。E-mail:sxdfqiuming@163.com
  • 基金资助:
    国家自然科学基金项目(51778641);陕西省自然科学基础研究计划项目(2019JQ-834);陕西省教育厅科研计划项目(19JK0963);延安市重点研发计划项目(2019ZCSY-006);延安大学科研计划项目(YDBK2017-32,YDZ2019-08,YDY2020-36)

Deformation Characteristics of Foundation Pit Excavation under the Combined Action of Diaphragm Wall and Impervious Curtain in Water-rich Sandy Stratum

QIU Ming-ming1, YANG Guo-lin2, SHEN Quan3, DUAN Jun-yi2, ZHANG Pei-ran2   

  1. 1. School of Architectural Engineering, Yan'an University, Yan'an 716000, China;
    2. School of Civil Engineering, Central South University, Changsha 410075, China;
    3. School of Civil Engineering, Hunan University of Technology, Zhuzhou 412007, China
  • Received:2019-07-29 Revised:2019-08-21 Published:2020-11-01 Online:2020-12-02

PDF

1434

摘要： 研究富水砂层地下连续墙深基坑变形特性对深基坑工程实践具有重要指导意义。以某车站地下连续墙深基坑工程为依托,通过数值模拟和现场实测方法研究降水渗流作用下富水砂层地下连续墙深基坑施工变形性状及其影响因素。研究结果表明:地下连续墙水平位移曲线分布随开挖深度加深由“斜线”形—“弓”形—倒“V”形演变,墙体最大水平位移Ux,max及其位置深度Hx,max与开挖深度he符合线性关系,最大水平位移约为(0.048%～0.082%)he,其深度位置约为(0.60～1.20)he;地表竖向位移曲线分布沿横向水平距离呈凹槽形,沉降槽随开挖深度增加而变宽、加深,沉降变形显著影响区为(1.0~1.5)he,距坑边(1/3~1/2)he处地表沉降最大;考虑地下连续墙与止水帷幕共同作用的富水砂层深基坑变形与实测结果更为吻合,且帷幕隔水和挡土作用对基坑变形影响显著;地下水位上升、砂层厚度加深均引起墙体水平位移和地表竖向位移增大,当风化砂岩层渗透系数较大时,渗透系数增加对坑外地表竖向位移的影响较墙体水平位移显著,合理的止水帷幕深度及间距参数有利于控制基坑变形和保持稳定性。

关键词: 深基坑, 富水砂层, 地下连续墙, 止水帷幕, 渗流, 变形性状, 数值模拟

Abstract: Researching the deformation characteristics of diaphragm wall foundation pit in water-rich sandy stratum is of important significance for engineering practice. The deformation characteristics and influence factors of a diaphragm wall foundation pit induced by deep excavation in water-rich sandy stratum were studied via numerical simulation and field monitoring. The horizontal displacement curve of diaphragm wall developed from an “oblique line” shape to that of a “bow” and then to an “inverted-V” shape with the deepening of excavation. The relation of maximum horizontal displacement Ux, max and its location Hx, max with excavation depth he could be described by linear function. Ux, max was about (0.048%~0.082%)he, and Hx, max was about (0.60~1.20)he. The vertical displacement of ground surface behaved as a groove-shaped curve with the increase of transverse horizontal distance. Such settlement groove grew wider and deeper with the deepening of excavation depth. The sensitive range of settlement deformation was about (1.0-1.5)he, and the maximum ground surface settlement occurred in (1/3~1/2)he from the foundation pit wall. The foundation pit deformation in consideration of the combined effect of diaphragm wall and impervious curtain in water-rich sandy stratum is consistent with observations. The waterproof and retaining function of impervious curtain has a significant effect on foundation pit deformation. The increment of both underground water level and sandy stratum thickness helped augment the horizontal displacement and ground surface's vertical displacement. The rising of permeability coefficient had a more significant impact on ground surface's vertical displacement than on the horizontal displacement of wall if the permeability coefficient is large. Reasonable depth and spacing of impervious curtain are conducive to control the deformation and stability of foundation pit.

Key words: deep foundation pit, water-rich sandy stratum, diaphragm wall, impervious curtain, seepage, deformation behavior, numerical simulation

中图分类号: 

*严禁使用本系统存储、处理、传输涉密信息*
本系统由北京玛格泰克科技发展有限公司设计开发 技术支持：support@magtech.com.cn