摘要
基于杭州某盾构隧道正上方大型基坑开挖工程实例,从实测数据角度分析门式加固和分区分块开挖措施对隧道变形的影响。通过对比基坑开挖期间各个阶段地铁隧道的竖向位移、水平位移和收敛变形情况,并结合变形控制值,研究了分区分块开挖过程中隧道的变形特点。结果表明:门式三轴搅拌桩加固,强化了土体的抗变形能力,能够有效减少上方卸载对盾构隧道的变形影响;分区分块的基坑开挖方式利用了时空效应,可以大大减小基坑开挖卸载过程中隧道的隆起变形;搅拌桩施工对隧道收敛值产生的影响远大于基坑开挖,以后类似工程宜采用微扰动施工工艺。
Based on a large foundation pit excavation project directly above a shield tunnel in Hangzhou, the influence of gabled reinforcement and divisional and block excavation measures on tunnel deformation were analyzed from the perspective of measured data.To study the deformation characteristics of tunnel in the process of divisional and block excavation, the vertical deformation, horizontal deformation and convergence deformation of subway tunnel in each stage during foundation pit excavation were compared, combined with the deformation control value. The analysis results showed that the reinforcement of "door" triaxial mixing pile strengthened the anti-deformation ability of soil and effectively reduced the deformation influence of upper unloading on shield tunnel. The excavation method of divisional and block foundation pit made use of the time-space effect, which greatly reduced the uplift deformation of the tunnel in the process of foundation pit excavation and unloading. The influence of mixing pile construction on the convergence value of tunnel was much greater than that of foundation pit excavation. Light disturbance construction technology could be adopted for similar projects in the future.
作者
马少俊
李鑫家
王乔坎
丁智
MA Shaojun;LI Xinjia;WANG Qiaokan;DING Zhi(Zhejiang Province Institute of Architectural Design and Research,Hangzhou 310006,Zhejiang,China;College of Civil Engineering and Architecture,Zhejiang University,Hangzhou 310058,Zhejiang,China;Department of Civil Engineering,Zhejiang University City College,Hangzhou 310015,Zhejiang,China)
出处
《隧道与地下工程灾害防治》
2022年第1期86-94,共9页
Hazard Control in Tunnelling and Underground Engineering
基金
浙江省重点研发计划资助项目(2017C03020、2020C01102)。
关键词
基坑开挖
盾构隧道
门式加固
分层开挖
实测分析
foundation pit excavation
shield tunnel
gabled reinforcement
layered excavation
measurement and analysis
