影响繁忙干线框构桥顶进效果的因素分析  

Research on the Factors Affecting the Busy Operation Lines during Jacking the Framed Structure Bridge

作　　者：沈宇鹏[1] 左瑞芳[1] 杨丽明 陈万成[3] 金振山 

机构地区：[1]北京交通大学,北京100044 [2]北京市重大项目建设指挥部办公室,北京100029 [3]天津市市政工程设计研究院,天津300051 [4]津滨城际铁路有限责任公司,天津300450

出　　处：《铁道工程学报》2017年第5期45-51,73,共8页Journal of Railway Engineering Society

基　　金：中央高校基本科研业务费专项资金(2015JBM064)

摘　　要：研究目的:框构桥作为后建铁路与公路穿越既有线时平改立的主要形式之一,在顶进施工过程中,各施工参数及工程条件会导致既有线轨道及路基的几何形位变化,对既有线上列车的安全运营产生不利影响。本文以既有津山铁路线下框构桥顶进工程为研究对象,采用MIDAS/GTS有限元软件,建立框构桥顶进施工模型,分析影响框构桥顶进效果的影响参数,并与现场监测结果进行对比,探讨施工参数和工程条件对既有线路基沉降、轨道水平及路基水平位移的影响规律。研究结论:(1)开挖进尺对既有路基沉降的影响显著,开挖进尺越大,路基沉降越大;(2)提高注浆强度能有效控制路基沉降,注浆强度每增加10 MPa,路基最大沉降量平均降低约10%;(3)顶进力是引起既有路基水平位移的主要原因,顶进力每增长50 kPa,水平位移增长约30%;(4)框构桥跨径、埋深及填料弹性模量对路基沉降、轨道水平及路基水平位移均有较大影响,且均随跨径的增大及埋深和填料弹性模量的减小而增大;(5)该研究成果可为同类框构桥工程的设计提供借鉴。Research purposes： When the post - construction railway or highway passes through the existing line, the framed structure bridge is one of the main forms of changing the plane cross to three - dimensional cross. In the process of jacking construction, the construction parameters and engineering conditions will lead to the geometric changes of track and subgrade of the existing lines, and have a negative impact on safety and stability of the train on the existing lines. Taking the jacking construction of framed structure bridge which is under the existing Tinajin - Sanhaiguan railway as research object, by using the MIDAS/GTS finite element software, the jacking construction model of framed construction bridge is established, the parameters which influence jacking effect of frame construction bridge are analyzed, and compared with actual engineering monitoring results, the influence of construction parameters and engineering conditions on the settlement of subgrade, the rail top level and the horizontal displacement of subgrade are discussed.Research conclusions： （ 1 ） Settlement of the operated subgrade is greatly affected by the excavation footage, and settlement becomes greater when the excavation footage become bigger. （2） Settlement of subgrade can be effectively controlled when the grouting strength increased, and the maximum settlement decreases by about 10% for every 10 MPa increase in grouting strength. （3） The jacking force is the main reason for the horizontal displacement of the operated subgrade, and the horizontal displacement increases by about 30% for every 50 MPa increase in jacking force. （4） The settlement depth and increase of of subgrade, the rail top level and the horizontal displacement of subgrade are greatly influenced by the span, elasticity modulus of subgrade filling of the framed structure bridge, and all the three targets increase with the the span and decrease of the depth and elasticity modulus of subgrade filling. （5）The research results can provide a refere

关 键 词：框构桥 顶进施工 轨道水平 参数优化 仿真计算 施工参数 

分 类 号：U25[交通运输工程—道路与铁道工程]