大断面城市隧道穿越复杂建筑物群的安全性控制研究

发布时间：2018-11-23 19:48

【摘要】：城市地下隧道工程施工对周边环境的影响一直以来是城市隧道工程施工需要解决的一个关键科学问题。采用浅埋暗挖法进行城市大断面隧道施工时,隧道施工必然会对周边环境(如建构筑物、地下管线、桥基等)产生一定程度的扰动,进而对其正常使用及结构安全及造成一定的影响。近几年来,随着我国城市地下工程建设高潮的兴起,这种工程将会越来越多,所带来的问题也将更加突出。因此,研究城市大断面浅埋暗挖隧道施工对邻近建筑群的影响及其控制具有重要的现实意义,其核心科学技术将会为类似工程的实施提供指导性作用。本论文在对国内外相关文献资料进行广泛调研的基础上,以厦门机场路一期工程莲前西路JC3标段大断面城市公路隧道穿越地表复杂建筑物群工程对象为研究背景,采用理论分析、数值模拟及现场实测、现场原位试验多种手段相结合的方法,对城市大断面浅埋暗挖隧道穿越既有建筑群工程所涉及的基础理论及关键技术等核心问题进行了深入研究,取得了以下主要成果： (1)针对大断面隧道下穿重要既有建筑物施工特点,根据隧道—地层—建筑物的相互作用关系,明确了隧道围岩地层变形是隧道穿越施工过程中建筑物安全性控制的关键点,因此在隧道施工过程中采取注浆加固地层(洞内和地表)是城市大断面隧道穿越建筑群的关键施工工序。 (2)根据本论文被研究对象的工程特点及周边环境特点,从建筑物的基础形式、建筑物与隧道的位置关系、建筑物的结构类型等方面,对建筑物群进行安全等级分类,提出了一种建筑物的安全等级分类方法,并为建筑物的控制标准建立提供依据。 (3)建筑物及围岩地层的控制标准是隧道施工变形过程控制的基础,本文以建筑物变位控制标准的研究为重点,提出了控制指标系统化的思想和方法,在此基础上,通过数值模型计算,得出了地层变形及建筑物变形的控制标准。在已有建筑物控制标准的基础上,根据现场实测结果,进一步引进建筑物裂缝的变化来确定地表沉降控制标准,为城市地下工程施工的地层变形控制标准体系的建立提供了一条新思路。 (4)根据本论文研究对象的建筑物的结构特点,认为隧道施工影响范围内的建筑物大多数为砌体结构,整体刚度小、柔性大,基本上能够与地表实现协同变形,在此基础上,根据建筑物与隧道之间的空间位置关系特点,在假定建筑物与地层协调变形的基础上,从理论上提出了砌体建筑结构与隧道相互作用的理论力学计算模型。 (5)以现场实际楼房为试验对象,对隧道下穿重要建筑物的相关计算参数的设计进行原位的注浆抬升试验和过程控制试验,建立以隧道围岩地层及建筑物结构变位的过程控制和以注浆抬升为主要途径的过程恢复,通过工程实践应用对上述理论进行印证,为类似工程提供参考。
[Abstract]:The influence of urban underground tunnel construction on the surrounding environment has always been a key scientific problem to be solved in urban tunnel construction. When the shallow excavation method is used in the construction of large section tunnel in the city, the tunnel construction will inevitably cause some disturbance to the surrounding environment (such as construction structure, underground pipeline, bridge foundation, etc.). Furthermore, it has a certain influence on its normal use and structural safety. In recent years, with the rise of the construction climax of urban underground engineering in our country, more and more such projects will be brought, and the problems will become more prominent. Therefore, it is of great practical significance to study the influence and control of shallow excavation tunnel construction on adjacent buildings, and its core science and technology will provide guidance for the implementation of similar projects. On the basis of extensive investigation of relevant documents at home and abroad, this paper takes the large cross-section urban highway tunnel of Lianqian West Road JC3 section of Xiamen Airport Road as the research background. By means of theoretical analysis, numerical simulation, field measurement and field in-situ test, In this paper, the basic theory and key technologies involved in the tunnel crossing through the existing buildings with large cross-section and shallow buried tunnels are deeply studied. The main achievements are as follows: (1) in view of the construction characteristics of the important existing buildings under the large section tunnel, according to the relationship between tunnel, stratum and building, It is clear that the deformation of surrounding rock stratum is the key point of building safety control in the process of tunnel crossing construction. Therefore, it is a key construction procedure for large section tunnels to use grouting to reinforce the strata (inside and on the ground) during the tunnel construction. (2) according to the engineering characteristics and the surrounding environment characteristics of the object studied in this paper, the safety grade classification of the building group is carried out from the aspects of the basic form of the building, the position relationship between the building and the tunnel, the structure type of the building, and so on. This paper presents a classification method of building safety grade, and provides the basis for building control standard. (3) the control standard of building and surrounding rock stratum is the foundation of deformation control in tunnel construction. This paper puts forward the idea and method of systematization of control index based on the research of building displacement control standard. Through numerical model calculation, the control standard of formation deformation and building deformation is obtained. On the basis of the existing building control standards, and based on the field measured results, the changes of building cracks are further introduced to determine the control standards of ground subsidence. It provides a new idea for the establishment of the control standard system of formation deformation in urban underground engineering construction. (4) according to the structural characteristics of the buildings studied in this paper, it is considered that most of the buildings in the influence area of tunnel construction are masonry structures, the overall stiffness is small, the flexibility is large, and the deformation can be realized in coordination with the surface basically. According to the characteristics of the spatial position relationship between the building and the tunnel, the theoretical mechanical calculation model of the interaction between the masonry structure and the tunnel is put forward theoretically on the basis of the assumption of the harmonious deformation between the building and the stratum. (5) the in-situ grouting uplift test and process control test are carried out for the design of the relevant calculation parameters of the important building under the tunnel, taking the actual building on site as the test object. In this paper, the process control of the displacement of tunnel surrounding rock strata and building structure and the process recovery of grouting uplift are established. The above theory is verified by engineering practice, which provides a reference for similar projects.
【学位授予单位】：北京交通大学
【学位级别】：博士
【学位授予年份】：2015
【分类号】：U455

【参考文献】