新建铁路桥梁斜穿既有高铁对高铁桥墩基础的影响分析  

Analysis of the influence of the new railway bridge diagonally crossing the existing high-speed railway on the pier foundation of the high-speed railway

作　　者：张华 Zhang Hua(China Railway Fifth Survey and Design Institute Group Co.,Ltd.,Beijing 102600,China)

机构地区：[1]中铁第五勘察设计院集团有限公司,北京102600

出　　处：《山西建筑》2025年第3期141-145,共5页Shanxi Architecture

基　　金：中铁第五勘察设计院集团有限公司2022年度科研计划课题(课题编号:T5Y2022-B03)。

摘　　要：为研究新建铁路桥梁小角度下穿既有运营高铁对高铁桥墩基础的影响,以新建六安铁路连续刚构桥下穿既有安九高铁跨安庆支线特大桥立交工程为背景,运用MIDAS-GTS NX软件,建立了新建铁路桥梁下穿既有高铁的三维有限元模型。研究表明:既有运营高铁下穿工程采用现浇支架施工,在支架预压阶段既有高铁附近地层受到大面积扰动,高铁桥墩基础受到附加荷载较大,对桥墩基础变形影响较大;采用小角度斜穿既有运营高铁,由于新建工程距离既有高铁基础较近,对高铁桥墩水平变形影响较大;邻近既有高铁的基坑施工采取有效防护措施,可显著降低新建工程对铁路的影响;新建下穿工程会引起既有高铁桥墩桩基承载力增加,针对有规划下穿工程的铁路桥梁设计,可通过有效措施提高基础承载力;既有高铁桥梁基础变形在新建下穿工程施工过程中具有动态累积效应,施工期间应加强对既有高铁桥墩基础变形监测,保证既有高铁安全。In order to study the influence of the new railway bridge passing under the existing high-speed railway at a small angle on the pier foundation of the high-speed railway,a three-dimensional finite element model of the new railway bridge crossing the existing high-speed railway under the background of the new Lu'an railway continuous rigid bridge crossing the existing Anqing branch bridge interchange project was established,and the MIDAS-GTS NX software was used to es-tablish a three-dimensional finite element model of the new railway bridge passing through the existing high-speed railway.The results show that:The cast-in-place support is used for the construction of the existing high-speed rail underpass pro-ject,and the stratum near the existing high-speed railway is disturbed in a large area during the bracket preloading stage,and the high-speed rail pier foundation is subjected to additional loads,which has a great impact on the deformation of the pier foundation;The existing operating high-speed railway is crossed diagonally at a small angle,and the horizontal de-formation of the high-speed rail pier is greatly affected because the new project is close to the existing high-speed rail foun-dation;Effective protective measures should be taken for the construction of foundation pits adjacent to the existing high-speed railway,which can significantly reduce the impact of new projects on the railway;The bearing capacity of the exist-ing high-speed railway pier pile foundation will be increased by the new underpass project,and the foundation bearing ca-pacity can be improved through effective measures for the design of railway bridges with planned underpass projects;The deformation of the existing high-speed rail bridge foundation has a dynamic cumulative effect in the construction process of the new underpass project,and the monitoring of the deformation of the existing high-speed rail pier foundation should be strengthened during the construction period to ensure the safety of the existing high-speed railway.

关 键 词：新建铁路 数值模拟 高铁桥梁 小角度斜穿 位移变形 基础承载力 

分 类 号：TU997[建筑科学—市政工程] U441.7[建筑科学—桥梁与隧道工程]