下穿高层建筑群浅埋暗挖小净距隧道施工力学与安全控制技术研究

发布时间：2018-03-04 04:18

本文选题：小净距　切入点：下穿　出处：《重庆交通大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着城市化的发展，城市人口将越来越密集，特别是大城市，地面交通已不能满足现有交通需要，城市交通地下化是未来发展的大方向。城市浅埋隧道建设以后会越来越普遍，所以对隧道开挖下穿高层建筑的施工力学研究为未来地下交通建设提供指导作用，具有非常现实的意义，本文以渝中连接隧道下穿农业银行住宅楼和办公楼小净距段为研究背景，采用理论分析和数值模拟的方法，重点对小净距隧道下穿农业银行两栋建筑全开挖过程进行力学分析，重点对各排基础下洞内断面拱顶竖向位移和拱腰水平位移，最大压应力，塑性区的开展，初支和二衬受力特征，地表沉降，房屋基础沉降和倾斜情况进行分析，同时对比改变开挖步序，先开挖左洞时以上各指标的数值变化情况，最后建立无房情况和先开挖隧道后在正上方建房的情况，以此分析由于房屋的存在，隧道开挖围岩变形与初支二衬受力情况及房屋的修建对先建隧道造成的影响。主要内容有以下几个方面： ①系统论述了国内外近接施工的施工方法，周边建筑与隧道相互影响分区及加固方案等各项研究成果，探讨目前存在的问题。 ②对近接施工进行理论研究，分析了近接施工隧道开挖，地层变形和受力特征及其传递规律，隧道开挖的影响范围及其诱发的地表沉降槽，地层变形特点及其控制原理，隧道-岩土体-结构的同台作用体系及其变形破坏特征分析 ③对小净距隧道下穿农业银行段进行全过程开挖分析，建立下穿段的三维有限元模型，，分析开挖过程中各排基础下洞内断面围岩的变形特点，塑性区的开展，初期支护和二衬的受力，地表沉降特征，房屋的基础沉降和倾斜情况，验证了现有设计支护方案完全能够满足结构自身及周边建筑的稳定性要求，得出了围岩的应力重分布特征，初支与二衬的受力特点，房屋的变形特点，并找出了开挖过程中的关键施工步及施工中应注意采取的措施。 ④对比分析改变开挖步序隧道自身及周边建筑的变形情况，得出在正穿高层建筑时，先开挖上方荷载较小一侧洞再开挖竖向荷载较大一侧洞室的原因。 ⑤对比分析在先有房后建隧道，无房及在先有隧道后建房三种工况下围岩、初支与二衬的受力特点，得出了在有房与无房时开挖隧道，房屋对洞室影响的范围及由于房屋存在两洞之间的相互影响程度，由于房屋的存在围岩变形，初支与二衬受力增长情况。同时得出了在先开挖隧道后建房，房屋对洞室的影响情况。 ⑥详细介绍近接施工中，从隧道施工、地层加固、房屋基础注浆和结构加固等方面稳定地层及结构的施工措施。
[Abstract]:With the development of urbanization, urban population will become more and more dense, especially in large cities, the ground traffic can no longer meet the existing traffic needs, urban traffic underground is the main direction of future development. The construction of shallow buried tunnels will become more and more common after the construction of urban shallow tunnels. Therefore, the study on the construction mechanics of the high-rise building under tunnel excavation provides guidance for the future underground traffic construction, which has very practical significance. In this paper, based on the research background of Yuzhong connecting tunnel through the residential building and office building of Agricultural Bank of China, using the method of theoretical analysis and numerical simulation, this paper focuses on the mechanical analysis of the whole excavation process of two buildings of Agricultural Bank of China under the tunnel of small clear distance. The vertical displacement of arch roof and horizontal displacement of arch waist, the maximum compressive stress, the development of plastic zone, the stress characteristics of initial support and second liner, the surface settlement, the settlement of building foundation and the situation of inclination are analyzed in detail. At the same time, by comparing and changing the order of excavation, the numerical changes of the above indexes during excavation of the left hole are first made. Finally, the situation of no house and the situation of constructing the house above the tunnel after excavation are established, so as to analyze the existence of the house. The deformation of surrounding rock in tunnel excavation and the stress situation of the first support and the second lining and the influence of building construction on the first construction of tunnel. The main contents are as follows:. The main contents are as follows: 1. This paper systematically discusses the construction methods of the adjacent construction at home and abroad, the interaction between the surrounding buildings and the tunnel and the reinforcement scheme, etc., and discusses the existing problems. (2) the theoretical study on the near-junction construction is carried out, and the characteristics of the tunnel excavation, the deformation and stress characteristics of the stratum and the law of its transmission, the influence range of the tunnel excavation and the induced surface subsidence trough, the characteristics of the formation deformation and the control principle are analyzed. Analysis of the coplatform action system and its deformation and failure characteristics of tunnel rock-soil-structure. (3) analyze the whole process of excavation of the small clear distance tunnel through Agricultural Bank, establish the three-dimensional finite element model of the lower section, analyze the deformation characteristics of the surrounding rock and the development of the plastic zone in each row of foundation during the excavation. The initial support and secondary lining force, the surface settlement characteristics, the foundation settlement and the slope of the building verify that the existing design support scheme can fully meet the stability requirements of the structure itself and the surrounding buildings. The stress redistribution characteristics of surrounding rock, the stress characteristics of the first and second linings and the deformation characteristics of the building are obtained. The key construction steps in the excavation process and the measures to be taken in the construction are also found out. (4) by comparing and analyzing the deformation of the tunnel itself and its surrounding buildings, it is concluded that when the tunnel passes through the high-rise building, the reason of excavation of the upper side of the tunnel with less load and then the larger vertical load of the tunnel is obtained. (5) comparing and analyzing the mechanical characteristics of surrounding rock under three working conditions of building tunnel after building first house, without house and building house after building first, the stress characteristics of initial branch and second lining are analyzed, and the excavation of tunnel is obtained when there is room and no room. The scope of the influence of the building on the tunnel and the degree of interaction between the two holes in the house, the deformation of the surrounding rock of the house, the increase of the initial support and the second lining force are obtained. At the same time, the excavation of the tunnel before the construction of the house is obtained. The influence of the house on the cave. 6. The construction measures of stabilizing stratum and structure from tunnel construction, stratum reinforcement, building foundation grouting and structure strengthening are introduced in detail.
【学位授予单位】：重庆交通大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U455.49;U451

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