盾构下穿施工对高速铁路轨道结构的影响研究  

Research on the Influence of Under-passing Shield Tunnel Construction on the Track Structures of High-speed Railway

作　　者：蔡小培[1] 蔡向辉[2] 谭诗宇 彭华[1] 郭亮武 

机构地区：[1]北京交通大学,北京100044 [2]中铁第一勘察设计院集团有限公司,西安710043

出　　处：《铁道工程学报》2016年第7期11-17,共7页Journal of Railway Engineering Society

基　　金：国家自然科学基金项目(61134003;51578053);北京市自然科学基金委员会-北京市科学技术研究院联合资助项目(L150003);北京高等学校青年英才计划(YETP0559);北京市科技新星计划(XX2013012)

摘　　要：研究目的:城市轨道交通盾构下穿高速铁路施工时,土体的扰动会导致上部既有线路结构产生轨道不平顺,对高速列车的安全运营产生非常不利的影响。本文考虑盾构隧道下穿施工、高速铁路结构间的相互作用关系,建立轨道-路基-土体有限元模型,分析盾构开挖过程中高速铁路轨道变形特征,并基于所建立的动力学模型探讨盾构下穿施工对列车运行的影响规律。研究结论:(1)轨道变形会随着盾构下穿施工不断增大,在开挖完毕后逐步趋于稳定,轨道垂向变形明显大于横向变形;(2)盾构开挖面位于线路中心线正下方时,轨道沉降变形速率、两股钢轨沉降差和钢轨横向位移最大,通过中心线后其值会逐渐减小;(3)轨道变形随盾构隧道埋深的增大而减小,随盾构隧道半径的增大而增大,基本呈线性关系;(4)列车通过盾构下穿影响区域时,对轮轨力及安全性指标影响显著,随列车速度的增加而增大;(5)盾构开挖面位于线路中心线正下方时,轮轨垂向力和轮重减载率的变化较为明显;(6)本研究成果对盾构下穿既有铁路工程的评估和风险控制具有一定的指导意义。Research purposes： When the urban rail transit shield under- pass the high -speed railway, soil disturbance will cause track irregularity of the existing line, which puts impact on the safe operation of high - speed train. In the paper, taking the interaction between shield construction and the structures of the high - speed railway into consideration, the finite element model of the track - subgrade - soil was established to analyze the deformation features of the track under shield tunneling. In addition the effect of shield tunneling on the train~ operation was discussed based on the dynamic model. Research conclusions： （ 1 ） The track deformation will continue to increase with the shield tunneling, and gradually come to a standstill after excavation. The results show that vertical deformation of the track is obviously larger than the lateral deformation. （2） The track settlement deformation rate, settlement difference of two rails and lateral deformation of rail will reach the maximum value when the excavation face is located under the center line of railway track, and the value will gradually reduce after the center line of the track. （3） The track deformation will decrease linearly with tunnel depth, and increase linearly with tunnel radius. （4） When train passing through the affected area of shield tunnel, the wheel - rail force and safety indexes are significantly affected, and increase as the speed increases. （5） The vertical wheel - rail force and wheel unloading rate change more obviously when the excavation face is located under the center line of railway track. （6） The research conclusions have certain instructional significance to the evaluation and risk control of under - passing the existing railway projects.

关 键 词：高速铁路 盾构施工 有限元分析 轨道变形 动力学 

分 类 号：U216.3[交通运输工程—道路与铁道工程]