新人工填筑土大断面隧道施工地层变形规律及控制技术

发布时间：2018-06-04 12:35

本文选题：新人工填筑土 + 超大断面隧道　；参考：《西南交通大学》2017年硕士论文

【摘要】：以贵阳铁路枢纽工程龙洞堡机场隧道为背景,综合运用现场测试、模型试验及数值计算方法,对超厚新人工填筑土地层超大断面隧道施工土体变形规律及其施工对策进行了研究。在对新人工填筑土自身固结特性研究的基础上,进一步研究了新人工填筑土条件下大断面隧道施工引起的土体变形规律,并据此提出了相应的施工控制对策。通过研究和总结取得以下成果:(1)通过理论分析及室内试验,初步认识了新人工填筑土的固结特性,在此基础上得到了龙洞堡机场隧道上覆新人工填筑土的固结沉降量。(2)综合应用现场测试、模型试验以及数值计算等技术手段,研究得到了新人工填筑土条件下隧道开挖引起的拱顶下沉与地表沉降之间的关系,并指出龙洞堡机场隧道上覆新人工填筑土的沉降主要是由于土体自身固结引起的。(3)以龙洞堡机场隧道为依托,基于大拱脚弧形导坑预留核心土台阶开挖法,研究了单一加固技术措施对控制新人工填筑土条件下暗挖大断面隧道地表沉降的作用效果,得到为控制沉降各种支护措施应综合采用:首先应进行超前支护,确保隧道开挖过程中的围岩稳定,同时应对隧道轮廓外侧全环加固,在此基础上,二次衬砌尽可能地紧跟初期支护施作。该研究成果直接指导了龙洞堡机场隧道下穿新人工填筑土段的修建,为进一步拓展软土地层中的隧道修建技术积累了经验。
[Abstract]:Taking the Longdongbao Airport Tunnel of Guiyang Railway Hub Project as the background, the field test, model test and numerical calculation method are used synthetically. In this paper, the deformation law of soil mass and its construction countermeasures are studied in the construction of super thick new artificial fill soil layer tunnel with super section. Based on the study of the consolidation characteristics of the new artificial filling soil, the deformation law of soil mass caused by the construction of large section tunnel under the condition of new artificial filling soil is further studied, and the corresponding construction control measures are put forward. By studying and summarizing the following results: 1) through theoretical analysis and laboratory tests, the consolidation characteristics of the new artificial soil are preliminarily understood. On the basis of this, the consolidation settlement of the newly constructed soil on the tunnel of Longdongbao Airport is obtained. The comprehensive application of field test, model test and numerical calculation are obtained, and some technical means, such as field test, model test and numerical calculation, are obtained. The relationship between the dome subsidence caused by tunnel excavation and the surface settlement under the condition of new artificial soil filling is obtained. It is also pointed out that the settlement of the newly constructed soil on the Longdongbao Airport Tunnel is mainly caused by the consolidation of the soil itself. The settlement is based on the Longdongbao Airport Tunnel and the excavation method of reserved core soil step based on the arc shaped guide pit with large arch foot. This paper studies the effect of single reinforcement technique on controlling the surface subsidence of large tunnel with large section excavated under the condition of new artificial soil filling. It is concluded that various supporting measures should be adopted comprehensively to control settlement: firstly, advance support should be carried out. In order to ensure the stability of surrounding rock during tunnel excavation, the surrounding rock should be strengthened outside the tunnel contour at the same time. On this basis, the secondary lining should be as close as possible to the initial support. The research results directly guide the construction of the new artificial fill section under the Longdongbao Airport Tunnel and accumulate experience for further developing the tunnel construction technology in the soft soil layer.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U455.4

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