【作者】 李然；

【导师】 刘润；

【作者基本信息】 天津大学 ， 岩土工程， 2014， 硕士

【摘要】 地铁作为城市公共交通线路的重要组成部分，近年来在我国处于高速发展阶段，但由于地铁隧道多于城市中进行修建，地上及地下构筑物分布较为密集，穿越施工涉及区域情况较为复杂，影响因素的多样性导致建设过程对周边土体的影响效果会随隧道的具体设计建造情况存在明显差别，确定实际方案时需对多种设计指标进行综合评估，以达到建设过程对周边结构物和正常社会秩序影响最小的目的。对单一影响因素作用下的土体响应变化规律进行更全面的认识是综合评估各项影响因素作用的前提。因此，地铁建设中普遍存在的主要影响因素及其对土体作用效果影响的变化规律需进一步进行研究整理。本文应用有限元模拟方法，针对影响暗挖隧道建设过程对周边土体作用效果的重要因素，系统研究了土体受影响导致变形的变化规律，以对实际工程的设计与评估工作提供参考建议。主要研究内容和结论如下：1.归纳相关研究进展，总结了地铁工程施工常用技术，整理了国内外关于地下工程建设对土体影响的研究手段，以有限元模拟方法对暗挖隧道建设对周边土体产生的影响进行了建模分析研究。2.研究了暗挖隧道施工中开挖沿线土体对隧道半径、埋深等影响因素的响应情况，利用数据结果揭示了暗挖隧道开挖支护过程中土体典型位置的位移发展历程，结果表明：隧道支护结构刚度不变情况下，当开挖步距与隧道埋深均相同时，隧道轴线上方地表土体沉降量随隧道半径增大而不断增大；当开挖步距与隧道半径均相同时，隧道轴线上方地表土体沉降量随埋深增大不断增大。且分析了这种土体变形变化规律的形成原因。3.通过数值模拟方法证明平行隧道暗挖施工所造成的土体变形与简单单孔隧道暗挖变形在影响因素方面存在很大差别，分析了平行隧道建设中不同隧道间距及埋深下土体代表性位置的最终位移情况，为实际工程问题的解决提供参考。4.针对南京地铁四号线工程实例，利用分析所得规律性结论确定开挖施工步骤及针对性的土体加固手段，通过有限元分析软件对实际工程进行建模分析，证实了所选工程手段的合理性与有效性，为施工建设提供了有价值的指导。更多还原

【Abstract】 As an important part of urban public traffic line, subway is rapidly developing inour country in recent years. But because of the complex environment of subwayconstruction, there would be distinct differences between the results caused bydifferent design schemes on the settlement of soil. In order to achieve the purpose ofminimum effects on soil and structures, analyses on the effects of influencing factorsare needed. Systematically researches are made in the paper on different effects onsoil settlement caused by the change of influencing factors by the way of numericalsimulation analysis. The study work is summarized as follows:1. The common techniques of subway construction are summarized in the paper.On the basis of summarizing the relevant research progress at home and abroad, theeffects on the soil settlement caused by different influencing factors are studied by theway of numerical simulation analysis.2. Researches are made on the rules of settlement changing affected by differentinfluencing factors such as the radius and the buried depth of tunnel. The results showthat the soil settlement on the surface above the tunnel will increase with the growthof tunnel radius when other influencing factors remain the same. And the soilsettlement on the surface above the tunnel will also increase with the growth of burieddepth when other factors remain the same. And the causes of these phenomenons havealso been analyzed.3. It has been proved that the soil settlement caused by the construction ofparallel bored tunnels is different from that caused by the construction of single boredtunnel. The settlement at the representative position of soil has also been analyzed toprovide a reference for actual project.4. The soil reinforcement methods and construction sequence of Gulou station ofNanjing subway line4are determined by using the aforementioned results. And theeffectiveness of the methods has been proved by numerical simulation analysis.更多还原