列车振动荷载作用下饱和砂层中盾构隧道及周边土体的动力响应分析  

Dynamic Response Analysis of Shield Tunnel in Saturated Sand Layer and SurroundingSoil under Train Vibration Load

作　　者：郝鑫 HAO Xin(North China University of Water Resources and Electric Power,Zhengzhou 450046,China)

机构地区：[1]华北水利水电大学,郑州450046

出　　处：《价值工程》2023年第15期162-164,共3页Value Engineering

摘　　要：地铁列车在运行过程中会产生一种特殊的循环振动荷载,振动荷载会降低饱和砂土土体承载力,导致隧道及周边土体沉降,甚至引起土体液化.本文以郑州轨道交通一号线为例,对特定区间的小半径曲线隧道进行监测,并结合MIDAS软件建立三维数值模型,以运营速度为研究对象,揭示了不同荷载参数下隧道结构、孔隙水压力、土体变形沉降的动力响应规律,探讨了运营状态下土体液化特征.结果表明:列车在小半径曲线段运营会加剧转弯半径内侧的孔隙水压力变化幅度;隧道周边土体的动力响应受运行速度、左右两线运营调度影响较大.A special kind of cyclic vibration load is generated during the operation of subway trains.The vibration load reduces the bearing capacity of saturated sandy soil,leading to settlement of the tunnel and surrounding soil,and even causing soil liquefaction.In this paper,taking Zhengzhou rail transit line 1 as an example,we monitor the small radius curve tunnel in a specific interval and establish a three-dimensional numerical model with MIDAS software to study the operational speed,reveal the dynamic response law of tunnel structure,pore water pressure and soil deformation and settlement under different loading parameters,and explore the characteristics of soil liquefaction under operational condition.The results show that:the operation of trains in small radius curve section will aggravate the magnitude of pore water pressure change inside the turning radius;the dynamic response of soil around the tunnel is influenced by the operation speed and the operation scheduling of left and right lines.

关 键 词：振动荷载 饱和砂土 小半径曲线 动力响应 

分 类 号：U270.1[机械工程—车辆工程]