渗流条件对土压盾构非满舱施工开挖面稳定性影响研究  

The Influence of Seepage Conditions on the Excavation Face Stability of Non-full Chamber Construction of Earth Pressure Shield

作　　者：胡涧楠 钱勇进 王璐 徐超[1,2] 朱伟 HU Jiannan;QIAN Yongjin;WANG Lu;XU Chao;ZHU Wei(Key Laboratory of Ministry of Education of Geomechanics and Embankment Engineering,Hohai University,Nanjing 210098,China;College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China;College of Enmronment,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [2]河海大学土木与交通学院,南京210098 [3]河海大学环境学院,南京210098

出　　处：《河南科学》2021年第2期229-236,共8页Henan Science

基　　金：国家重点基础研究发展计划(973计划)(2015CB057803)。

摘　　要：土压平衡盾构因排土效率高、占地面积少等特点被广泛使用于地铁隧道建设.工程中为进一步提高盾构掘进效率,常采用非满舱掘进模式进行隧道施工,而富水地层中非满舱掘进常常遇到渣土泥浆化喷出、开挖面失稳引起超挖量大等问题.针对渗流条件对非满舱施工开挖面稳定性影响,通过数值模拟研究稳态渗流条件下非满舱掘进模式开挖面的渗流场,并基于筒仓模型,计算筒仓边界面上的渗流作用力,建立了考虑渗流条件的非满舱掘进开挖面极限支护应力计算公式,分析了不同舱土高度下埋深、渗透系数、地层摩擦角、黏聚力对开挖面极限支护应力影响.结果表明,随着埋深、内摩擦角、渗透系数的增大,黏聚力减小,开挖面极限支护应力增大;渗流作用对非满舱掘进时开挖面的影响较大,且随着埋深的增大,渗流作用影响越来越显著.The earth pressure balance shield,which has the characteristics of high soil removal efficiency and less occupation area,is widely used in metro tunnel construction.In order to further improve the efficiency of shield tunneling,tunnel construction is usually carried out by non-full chamber tunneling mode.In water-rich stratum it often encounters the problems such as mud melting and ejecting and large over excavation due to the instability of excavation face.In view of the influence of seepage condition on the stability of excavation face under non-full chamber construction,the seepage field of excavation face under non-full chamber tunneling mode under steady seepage condition was studied by numerical simulation.Based on the silo model,the seepage force on the silo boundary was calculated,and a formula for calculating the ultimate support stress of excavation face considering seepage condition was established.The influence of burial depth,permeability coefficient,formation friction angle and cohesion force under different tank soil height on the ultimate support stress of excavation face was analyzed.The results show that with the increase of buried depth,internal friction angle and permeability coefficient,and the decrease of the cohesive force,the ultimate supporting stress of excavation face increases.The seepage action has a great influence on the excavation face during non-full chamber excavation,and the influence of seepage action becomes more and more significant with the increase of buried depth.

关 键 词：盾构隧道 开挖面稳定 筒仓模型 支护压力 渗流作用 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]