大断面软岩隧道近距离下穿滑坡段支护结构及围岩变形控制技术研究

发布时间：2018-03-08 06:40

本文选题：隧道　切入点：滑坡　出处：《西南交通大学》2015年硕士论文　论文类型：学位论文

【摘要】：滑坡及软弱围岩的存在给隧道的建设及后期的运营带来了较大的挑战,如何对软弱围岩的变形进行有效的控制,确保隧道—滑坡体系在施工及运营过程中的安全是工程设计与施工面临的一个难题。本文以渭河隧道下穿北山滑坡段为背景,针对隧道下穿巨型滑坡与软岩大断面的工程特点,通过资料调查,工程类比,数值模拟,现场监控量测等方法和手段,展开对围岩变形控制技术与隧道—滑坡相互作用关系的研究,最终提出了一套有效的软弱围岩变形控制施工方法。主要研究内容及成果如下：(1)通过对工程文献资料的调查研究,总结了软岩隧道及类似工程常用开挖支护方法的特点和应用现状。(2)通过隧道开挖与支护对围岩稳定影响的理论分析,结合软岩的力学特征与渭河隧道下穿滑坡施工段的工程特点,对隧道开挖后可能出现的问题进行了预测,并针对以上可能出现的问题提出了3种开挖支护方案。(3)结合渭河隧道下穿滑坡段的实际工程情况,对本文提出的3种开挖支护方案的地层—结构力学行为特征进行了数值模拟分析,表明“双侧壁导坑—加强型复合式衬砌结构”方案在控制围岩变形,保证支护结构安全方面具有明显的优势,因此,推荐该方案作为渭河隧道下穿滑坡段施工的优选方案。(4)通过数值模拟结果,分析了隧道—滑坡体系相互作用的两种表现形式,并指出在渭河隧道下穿滑坡施工段,隧道开挖对滑坡体的影响较小,而极端条件下的降雨会对滑坡体的稳定造成较大影响,应该作为安全控制的重点。(5)对渭河隧道下穿滑坡施工段进行了现场监控量测,监测结果表明：本文提出的“双侧壁导坑—加强型复合式衬砌结构”方案对软弱围岩的变形能起到较好的控制作用。同时,通过监测数据与数值模拟结果的比较,证明了本文采用的数值模拟方法是可行的,能基本反映工程的实际情况。
[Abstract]:The existence of landslide and soft surrounding rock brings great challenge to tunnel construction and later operation. How to control the deformation of soft surrounding rock effectively, It is a difficult problem for engineering design and construction to ensure the safety of tunnel-landslide system during construction and operation. This paper takes the Weihe tunnel under the Beishan landslide as the background, aiming at the engineering characteristics of giant landslide and large section of soft rock under the tunnel. Through the methods and means of data investigation, engineering analogy, numerical simulation, field monitoring and measurement, the study on the relationship between the deformation control technology of surrounding rock and the interaction between tunnel and landslide is carried out. Finally, a set of effective construction methods for controlling the deformation of weak surrounding rock are put forward. The main research contents and results are as follows: 1) through the investigation and study of engineering literature, This paper summarizes the characteristics and application status of common excavation and support methods for soft rock tunnel and similar projects. The influence of tunnel excavation and support on the stability of surrounding rock is analyzed theoretically. Combined with the mechanical characteristics of soft rock and the engineering characteristics of the construction section of Weihe tunnel through landslide, the possible problems after tunnel excavation are forecasted. In view of the above possible problems, three kinds of excavation and support schemes are put forward, which are combined with the actual engineering situation of the landslide section under the Weihe tunnel. In this paper, the characteristics of stratigraphic and structural mechanical behavior of three kinds of excavation and support schemes proposed in this paper are numerically simulated and analyzed. The results show that the scheme of "double sidewall guide pit reinforced composite lining structure" is used to control the deformation of surrounding rock. In order to ensure the safety of the supporting structure, it is recommended that the scheme should be used as the optimal scheme for the construction of the underpass landslide section of the Weihe tunnel. Through the numerical simulation results, the two forms of the interaction between the tunnel and the landslide system are analyzed. It is also pointed out that the influence of tunnel excavation on landslide is relatively small, while rainfall under extreme conditions will have a great impact on the stability of landslide. It should be regarded as the key point of safety control.) the construction section of Weihe tunnel under the landslide is monitored and measured on the spot. The monitoring results show that the "double-sidewall guide pit reinforced composite lining structure" scheme proposed in this paper can control the deformation of soft surrounding rock better. At the same time, through the comparison of monitoring data and numerical simulation results, It is proved that the numerical simulation method used in this paper is feasible and can basically reflect the actual situation of the project.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.49

【相似文献】