摘要
TBM在迎坡向上掘进时,随着坡度的增大,掘进机与接触岩土体间摩擦力增大,且掘进力的竖向分力增大,会对TBM隧道周围围岩体的应力、变形以及地表沉降产生一定的影响,因此研究大纵坡TBM施工时坡度对围岩及地表的影响具有重要意义。以重庆市轨道交通9号线刘家台—鲤鱼池区间双线隧道施工为例,基于力学平衡公式以及有限元模拟,将纵坡坡度设定为参数变量,分析TBM迎坡掘进不同坡度时对隧道周边地层稳定性的影响;探究TBM在不同坡度隧道开挖时引起的围岩应力变化规律,以及围岩竖向、横向变形和地表沉降规律,进而得到控制TBM迎坡掘进的安全措施。该研究成果可为大纵坡TBM施工安全提供可靠依据。
When TBM is heading up the gradient,with the increase of gradient,the friction between the TBM and the contact rock and soil increases,and the vertical component of the driving force increases,which will have a certain impact on the stress,deformation and surface settlement of the surrounding rock mass around the TBM tunnel.Therefore,it is of great signifi cance to study the influence of the gradient on the surrounding rock and the surface of the TBM tunnel.Taking Liujiatai--Liyuchi section of Chongqing rail transit line 9 as an example,based on the balance formula of force and finite element simulation,the longitudinal gradient is set as parameter variable,and the impact of TBM on the stability of surrounding stratum is analyzed.The paper explores the stress change pattern of surrounding rock caused by TBM excavation in different gradient tunnels,as well as the vertical and lateral deformation of surrounding rock and the pattern of surface settlement,and takes the safety measures to control the heading of TBM.The research results provide a reliable basis for the construction safety of TBM with steep longitudinal gradient.
出处
《现代城市轨道交通》
2021年第7期74-81,共8页
Modern Urban Transit
关键词
城市轨道交通
TBM施工
坡度
围岩
地表沉降
影响分析
urban rail transit
TBM construction
gradient
surrounding rock
surface settlement
impact analysis
