摘要
以银西铁路某隧道为依托,利用现场测试、数值模拟方法对大断面土质隧道围岩压力、二次衬砌内力、拱架应力、混凝土内力展开研究。结果表明:大断面土质隧道围岩压力大致分为急剧增长、减速增长、趋于平缓三个阶段,在空间分布上,表现为左侧>右侧、拱顶>仰拱的变化规律;围岩接触压力在空间范围内表现为拱顶、拱底较大。初支混凝土变化曲线基本呈受压状态,拱顶处围岩压力值较大;随着初期支护闭合成环,围岩应力与位移均表现出随时间增加而减少的趋势,建议施工过程应及时将衬砌结构封闭成环以改善结构整体应力及位移状态。
Based on a tunnel of Yinchuan-Xi’an High-speed Railway,the research methods of field test and numerical simulation are used to study the surrounding rock pressure,secondary lining internal force,arch stress and concrete internal force of large section soil tunnel.It is concluded that the surrounding rock pressure of large section soil tunnel can be roughly divided into three stages:rapid growth,deceleration growth and flattening.In terms of spatial distribution,it shows the change law of left side>right side,arch crown>inverted arch;the contact pressure of surrounding rock shows that the arch crown and arch bottom are large in space.The variation curve of the initially supported concrete basically presents the state of compression,and the pressure value of the surrounding rock at the arch crown is large;with the initial support closed into a ring,the stress and displacement of surrounding rock show a decreasing trend with the increase of time.Therefore,it is suggested to close the lining structure into a ring as soon as possible in the construction process to improve the overall stress and displacement state of the structure.
作者
范志远
FAN Zhiyuan(China Railway 12^(th) Bureau Group 4^(th) Engineering Co.Ltd.,Xi’an Shaanxi 710054,China)
出处
《铁道建筑技术》
2021年第10期40-44,共5页
Railway Construction Technology
基金
中国铁路总公司科技研究开发计划(2017G007-G)。
关键词
大断面土质隧道
围岩压力
复合衬砌
时空效应
数值分析
现场监测
large section soil tunnel
surrounding rock pressure
composite lining
time-space effect
numerical analysis
field monitoring
