沈阳站地下通道开挖对下部盾构隧道的影响研究

发布时间：2018-01-09 20:24

本文关键词：沈阳站地下通道开挖对下部盾构隧道的影响研究　出处：《东北大学》2013年硕士论文　论文类型：学位论文

【摘要】：随着城市地铁建设的发展,地铁线路的网络系统将越来越完善。在地铁沿线开挖基坑将不可避免。基坑开挖使下部地铁隧道和车站的原有受力平衡被打破,必然引起应力的重新分布,从而引起地铁隧道产生相应的内力变化和变形。论文结合哈大客专沈阳站地下通道改造工程沈阳地铁一号线沈阳站站-云峰北街站监测项目,研究基坑开挖对下部既有盾构隧道管片的影响。首先对盾构隧道等效连续化模型进行了研究,并引入风险分析的相关概念对差异沉降做了重点研究。然后,对哈大客专沈阳站地下通道改造工程沈阳地铁一号线沈阳站站-云峰北街站监测项目进行了实测分析：在东侧基坑开挖过程中,盾构隧道道床实测最大累计上浮值发生在上部土体卸载完毕时,于东侧基坑中心断面位置,值为4.39mm；在西侧基坑及暗挖段开挖过程中,盾构隧道道床实测最大累计上浮值发生在上部土体卸载完毕时,于暗挖段与西侧基坑过渡位置,值为5.64mm。论文根据哈大客专沈阳站地下通道实际工况进行了数值模拟分析并总结了下部隧道管片的变形规律：在地下通道开挖过程中,下部盾构隧道横向断面产生竖鸭蛋形状的平面变形。管片纵向变形曲线呈正态分布；对于基坑中心断面,卸载完毕管片拱顶隆起乎均值为6.31mm,约为土体回弹平均值的36.97%；管片拱底隆起平均值为2.40mm,约为拱顶隆起平均值的38.35%；卸载完毕管片变形纵向影响范围约为基坑开挖长度的2.5倍。最后,通过不同工况的对比分析得出：暗挖段桩基托换对下部盾构隧道管片影响不大可忽略不计。
[Abstract]:With the development of urban subway construction, the network system of subway line will be more and more perfect. The excavation of foundation pit along the subway line will be inevitable. The excavation of foundation pit will break the original force balance of the lower subway tunnel and station. The redistribution of stress is inevitable. In order to cause the subway tunnel to produce the corresponding internal force changes and deformations. This paper combined with the transformation of underground passage project Shenyang Metro Line 1 Shenyang Station-Yunfeng North Street Station monitoring project. The influence of foundation pit excavation on the segment of the existing shield tunnel is studied. Firstly, the equivalent continuum model of shield tunnel is studied, and the related concept of risk analysis is introduced to study the differential settlement. The monitoring project of Shenyang Station-Yunfeng North Street Station of Shenyang Metro Line 1 is analyzed: in the course of excavation of foundation pit on the east side. The maximum accumulated floating value of shield tunnel bed occurred when the upper soil was unloaded, and the value was 4.39 mm at the center section of the eastern foundation pit. During the excavation process of the west excavation and the excavated section, the maximum accumulated floating value of shield tunnel bed occurred when the upper soil was unloaded, and the transition position between the excavated section and the west foundation pit was taken place. The value is 5.64mm. according to the actual working conditions of the underground passage of the Hada Ke special Shenyang station, the paper carries on the numerical simulation analysis and summarizes the deformation law of the lower tunnel segment: in the excavation process of the underground tunnel. The horizontal deformation of the vertical duck egg is produced in the transverse section of the lower shield tunnel. The longitudinal deformation curve of the segment is normal distribution. For the central section of the foundation pit, the average uplift of the arch is about 6.31 mm, which is about 36.97 of the average value of the soil springback. The average value of segment arch uplift is 2.40 mm, which is 38.35 mm of the average value of arch top uplift; The longitudinal influence range of segment deformation after unloading is about 2.5 times of excavation length. Finally. Through the comparison and analysis of different working conditions, it is concluded that the influence of pile foundation underpinning on the lower shield tunnel segment is not negligible.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU94;U455.43

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