摘要
为研究湿陷性黄土公路隧道上跨施工对既有铁路隧道结构变形的影响,以崤函大道公路工程重丘2号隧道上跨蒙华铁路新乔隧道为工程背景,应用有限元软件Midas GTS NX建立三维数值模型并模拟其施工过程。首先选用灰土挤密桩加固湿陷性黄土隧道基底,以满足地基的承载力要求;然后,分析新建隧道上跨施工过程对既有隧道范围影响;最后,采用Midas GTS NX建立数值模型分析既有隧道结构受力与竖向位移变化规律。结果表明:灰土挤密桩可有效提高隧道基底承载力,满足施工要求;新建隧道上跨既有隧道施工要注重既有隧道各敏感部位隆起量,并需及时调整支护方案;所采用的重丘2号隧道施工方法合理可行,新乔隧道结构变形与沉降都在允许范围之内,既有隧道可正常运行,为类似空间结构隧道施工提供参考依据。
In order to study the influence of the upper span construction of collapsible loess tunnel on the structural deformation of the existing tunnel,taking the Xinqiao tunnel of Menghua Railway on Chongqiu No.2 tunnel of Xiaohan Avenue Road project as the engineering background,a three-dimensional numerical model is established and its construction process is simulated by using the finite element software Midas GTS NX.Firstly,lime soil compaction pile is selected to strengthen the foundation of collapsible loess tunnel to meet the requirements of foundation bearing capacity;Then,the influence of the construction process of the upper span of the new tunnel on the scope of the existing tunnel is analyzed empirically;Finally,Midas GTS NX is used to establish a numerical model to analyze the variation law of stress and vertical displacement of the existing tunnel structure.The results show that:Lime soil compaction pile can effectively improve the bearing capacity of tunnel foundation and meet the construction requirements;In the construction of the new tunnel over the existing tunnel,attention should be paid to the uplift of each sensitive part of the existing tunnel and the support scheme should be adjusted in time;The construction method of Chongqiu No.2 tunnel is reasonable and feasible.The structural deformation and settlement of Xinqiao tunnel are within the allowable range,and the existing tunnel can operate normally.
作者
于力昌
张鹏
李永靖
王松
YU Lichang;ZHANG Peng;LI Yongjing;WANG Song(No.5 Engineering Co.,Ltd.,CCCC First Engineering Bureau,Zhengzhou 451450,China;School of Civil Engineering,Liaoning Technical University,Fuxin 123000,China)
出处
《建筑结构》
CSCD
北大核心
2022年第S01期3148-3153,共6页
Building Structure
基金
国家自然科学基金资助项目(51974146、52174078)
关键词
湿陷性
灰土挤密桩
上跨施工
数值模拟
结构变形
collapsibility
lime-soil compaction pile
over-span construction
numerical model
structural deformation
