大断面黄土隧道近距离下穿桥梁桩基变形控制技术  

DEFORMATION CONTROL TECHNOLOGY OF BRIDGE PILE FOUNDATION N LARGE SECTION LOESS TUNNEL AT CLOSE DISTANCE

作　　者：李继光 Li Ji-guang

机构地区：[1]中铁二十局集团第二工程有限公司,西安710021

出　　处：《建筑技术开发》2024年第4期109-112,共4页Building Technology Development

基　　金：中国国家铁路集团有限公司科技研究开发计划项目(P2018G048)。

摘　　要：以西延铁路洛川隧道下穿S304省道黑木沟中桥为例,针对高速铁路大断面黄土隧道近距离下穿桥梁桩基时,施工变形控制难、施工风险大等特点,提出对通行道路的导改、隧道开挖采用3台阶临时仰拱法(腰梁式)、内支护和锁脚锚管的加强等措施,现场监控量测数据表明均未出现一级预警状态,地表、桥梁和桩基均处于正常状态,解决了高速铁路大断面黄土隧道近距离下穿既有公路桥梁桩基施工安全,形成了一套大断面黄土隧道近距离下穿桥梁桩基变形控制技术,可为类似工程施工提供技术借鉴。Taking the Luochuan Tunnel of the West Extension Railway through the S304 Provincial Highway Heimugou Middle Bridge as an example,for high-speed railway large-section loess tunnels when they penetrate the bridge pile foundation at close range.The characteristics of difficult construction deformation control and large construction risk.Measures such as the guidance and modification of the passage road,the use of the three-step temporary arch method(waist beam type)for tunnel excavation,the strengthening of the inner support and the anchor pipe with lock feet are proposed.The on-site monitoring and measurement data showed that there was no first-level warning state,the surface,bridges and pile foundations are in normal condition,it solves the safety of pile foundation construction of existing highway bridges under the close-range undersection of high-speed railway large-section loess tunnels,A set of large-section loess tunnel close down bridge pile foundation deformation control technology was formed,it can provide technical reference for similar engineering construction.

关 键 词：大断面黄土隧道 近距离下穿 桥梁桩基 变形控制 

分 类 号：U443.15[建筑科学—桥梁与隧道工程]