基于岩土控制变形分析法的软弱围岩隧道开挖变形控制技术

发布时间：2018-01-07 13:05

本文关键词：基于岩土控制变形分析法的软弱围岩隧道开挖变形控制技术　出处：《长安大学》2015年硕士论文　论文类型：学位论文

【摘要】：随着19世纪现代高能炸药的出现以及爆破、风钻技术的发展,隧道机械化开挖取得了长足进步,基于岩承理论的新奥地利隧道修建法(NATM)的诞生及其在世界范围盛行标志着地下工程设计施工技术理论趋向成熟。隧道工程主要是开挖与支护的问题,即如何安全地开挖、合理地支护以保证围岩-支护体系的安全,并确保其长期稳定性。随着隧道的发展,传统方法对复杂地质软弱围岩环境及长大规模隧道的安全开挖掘进已显得有些乏力,我国地下工程事故发生率也较高,其中地下水及围岩环境、地质情况和人为失误等占主要原因,软弱围岩环境下的隧道开挖一般变形大、工期长、成本高、易发生事故。岩土控制变形分析法(ADECO-RS,新意法)利用对掌子面-超前核心土的预加固及洞室预约束等措施保证极困难围岩条件下的洞室稳定性问题,事实也证明:控制了隧道预收敛及挤出变形,即控制了洞室在开挖过程中变形的最初原因,也就控制了洞室变形,能够保证隧道掘进过程中的安全。论文统计分析了截止2013年底我国在建及已建成特长公路隧道的施工事故,归纳分析了我国公路隧道施工过程中事故类型、发生原因及对策;基于岩土控制变形分析法提出了软弱围岩的定义,总结了软弱围岩的特性及各类围岩在隧道开挖过程中的力学特性、变形情况及工程影响,进而对软弱围岩进行了细化分级,并根据围岩分级和亚分级标准提出了不同类别的软弱围岩工程对策;根据收敛约束法和对数螺旋线法,分析掌子面及洞室在开挖过程中的稳定性,以及围岩亚分级标准下方案的可施工性,并基于围岩亚分级标准给出各级围岩环境下洞室开挖的合理工法与支护措施;总结新奥法及岩土控制变性分析法在软弱围岩环境下的典型开挖方法,认为在软弱围岩环境下的隧道开挖,洞室掌子面无法自稳,应当采取预约束/加固措施,并以IV2级亚分级为软弱围岩分级分界线,高于此级别的围岩环境下隧道开挖较安全,而低于此分级级别的围岩在开挖过程中应在约束、加固,或干预措施上予以充分重视。
[Abstract]:With the advent of the nineteenth Century modern high explosives and blasting, the development of pneumatic technology, tunnel excavation mechanization has made considerable progress, construction method based on the theory of new Austria bearing rock tunnel (NATM) and its marks of underground engineering design and construction techniques and theories tend to mature in the world. The prevalence of tunnel engineering is mainly excavation and supporting the problem is how to safely and reasonable supporting excavation, in order to ensure the safety of surrounding rock supporting system, and ensure the long-term stability of the tunnel. With the development of the traditional method of complex geological weak surrounding rock and long large-scale tunnel safety excavation has been somewhat weak, underground engineering accidents in our country also has a high incidence rate, the groundwater and surrounding environment, geological conditions and human errors accounted for the main reason, the general deformation, the weak surrounding rock tunnel excavation of long period, high cost, easy hair The accident analysis method. To control the deformation of rock and soil (ADECO-RS new method) to ensure stability of the surrounding rock cavern extremely difficult conditions by using the tunnel face - ahead of the core soil reinforcement and excavation appointment beam and other measures, also proved: control the convergence of tunnel and pre extrusion deformation, namely the control of the initial cause of deformation in tunnel in the process of excavation, we can control the tunnel deformation, to ensure the safety in the process of tunnel excavation. The statistical analysis by the end of 2013 in China and has built a construction accident in highway tunnel, analyzes the types of accidents in our country highway tunnel construction process, causes and countermeasures; geotechnical control deformation analysis method is proposed based on the definition of soft rock, summarizes the characteristics of surrounding rock and all kinds of soft rock in tunnel excavation mechanics characteristics during deformation, and the effects of soft rock in engineering. For detailed classification, and puts forward the Countermeasures of different types of soft rock engineering based on surrounding rock classification and sub classification standard; according to the convergence confinement method and logarithmic spiral method, stability analysis of tunnel face and tunnel during excavation, and the surrounding rock sub classification standard under the scheme of construction, and based on the reasonable method of surrounding rock sub classification the standard given levels of surrounding rock excavation and supporting measures; the typical methods of NATM excavation and geotechnical control degeneration analysis method in weak surrounding rock, that in the weak surrounding rock tunnel excavation, excavation face cannot be stabilized, should take an appointment / beam reinforcement measures, and to grade IV2 the sub level for weak surrounding rock classification boundaries, higher than this level of surrounding rock tunnel excavation is relatively safe, but lower than that of the surrounding this grading level should be constrained, reinforcement in the excavation process, or intervention. Give full attention to the application.

【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U455.4

【参考文献】