西安地铁车站深基坑变形规律FLAC模拟研究  

Research on the Deformation Law of Deep Foundation Pit of Metro Station in Xi'an by FLAC Simulation

作　　者：任建喜[1] 张引合[1] 张琨[1] 高丙丽[1] 

机构地区：[1]西安科技大学,西安710054

出　　处：《铁道工程学报》2011年第3期90-93,共4页Journal of Railway Engineering Society

基　　金：陕西省教育厅科研计划资助项目资助(2010JK667);高等学校博士学科点专项科研基金资助(20096121110004)

摘　　要：研究目的:西安是西北黄土地区第一个修建地铁的城市,地铁车站深基坑的开挖平面尺寸大、基坑暴露时间长、基坑变形控制等级高,西安又处于特殊的黄土地区,基坑壁岩土体主要为黄土及黄土状土,上部具有湿陷性,与国内外已开挖建成的地铁车站的城市的地质差异较大,车站深基坑围护设计可借鉴的经验较少。因此,急需开展地铁车站深基坑变形规律研究,为西安地铁其它车站深基坑围护结构设计与优化提供帮助。研究结论:以西安地铁2号线北大街车站深基坑工程为背景,建立了深基坑围护结构施工过程FLAC模拟计算模型,制定了车站深基坑施工监测方案,分析了围护桩的变形、钢支撑轴力变化和锚索受力变化的规律。结果表明,桩体位移是围护结构变形特性的直接反映,而钢支撑和锚索对深基坑变形有明显的限制作用。计算结果和监测结果基本一致。Research purposes：Xi＇an is the first city to build the urban metro in loess area in the northwest area in China.The deep foundation pit of metro station has the following features：big excavation plane size,long exposure time of foundation pit and high grade of controlling the foundation deformation.And Xi＇an is in the special loess area,and the rock-soil mass of the foundation wall is mainly of loess and loess-like soil with the collapsibility on the top,so Xi＇an is big different in geology from the city where metro station have been built at home and abroad,and there is little experience of supporting design of deep foundation pit of metro station to learn.Thus,it is necessary to do the research on the deformation law of deep foundation pit of metro station for the purpose of offering helps to design and optimize the supporting structure of the foundation pit of other metro stations in Xi＇an. Research conclusions：The simulation of the on excavation process of the deep foundation pit of Beidajie Metro Station of Line 2 of Xi＇an metrol was made with FLAC software to work out the monitoring plan of the deep foundation pit of the station.The analysis of the horizontal deformation of the retaining piles,the axial force changes of steel support,the change law of load bearing of the cables was made.The results showed that the displacement of pile directly reflected deformation characteristics of the retaining structure,while the steel support and cables obviously limited the deformation of foundation pit.The calculation results was basically in accordance with the monitoring results.

关 键 词：地铁车站 深基坑 围护结构 变形规律 FLAC模拟 现场监测 

分 类 号：U121[交通运输工程]