跨线桥桩基施工对既有高铁隧道的影响研究

发布时间：2018-06-09 03:07

本文选题：桩基础施工 + 高铁隧道　；参考：《湖南科技大学》2016年硕士论文

【摘要】：近年随着高铁建设的蓬勃发展,新建桥梁由于受线路规划、地理空间等原因,有时不可避免地需要跨越高铁隧道。而大多数桥梁采用桩基础,这些桩基础可能位于隧道侧面甚至上方。桩基础在施工时会扰动桩周土体,使周围土体和隧道发生相互作用,严重者将引起铁路轨道倾斜,围岩变形衬砌开裂渗水,发生重大工程事故。而目前国内外对这方面的研究较少,因此研究桩基础施工对既有高铁隧道的影响具有十分重要的工程意义。本文以跨九华大道K2+942.244处苞谷垄隧道桥桩基施工工程为依托,针对以上问题,采用工程设计、数值分析、现场监测等方法进行研究,具体内容如下:1.根据现有研究成果分析路基工作区影响深度对既有隧道结构的影响,得出架桥跨越隧道的可行性,并按规范要求进行桥梁上下部结构设计。2.根据依托工程地形地貌特征和地质分布情况,运用ANSYS软件建立三维数学分析模型,用FLAC3D软件动态模拟桩基施工对既有高铁隧道结构的受力与变形影响,得出隧道结构变形、桩周土体水平位移规律,判断隧道所处的安全状态。并指导桩基施工,优化监控量测方案。3.根据数值模拟分析结果,结合本工程特点和相关规范,对监测方案进行优化布置,包括监测项目、监测手段、监测点及断面、监测频率等。并将监测数据与数值模拟结果进行对比分析,更准确的判断隧道所处的安全状况。分析表明两者在隧道结构变形规律等方面具有一致性,影响隧道结构变形的主要原因是桩基与隧道结构间距。
[Abstract]:In recent years, with the rapid development of high-speed railway construction, new bridges are sometimes inevitably needed to cross high-speed railway tunnels due to line planning, geographical space and other reasons. Most bridges use pile foundations, which may be located on or above the side of the tunnel. The soil around the pile will be disturbed during the construction of the pile foundation, and the interaction between the surrounding soil and the tunnel will take place. In the serious case, the railway track will tilt, the surrounding rock deformation and lining will crack and seepage, and serious engineering accidents will occur. However, there is little research on this aspect at home and abroad, so it is of great engineering significance to study the influence of pile foundation construction on the existing high-speed railway tunnel. In this paper, based on the construction project of pile foundation of Baogu Ridge tunnel bridge across K2 942.244 of Jiuhua Avenue, the engineering design, numerical analysis and site monitoring are adopted to study the above problems. The concrete contents are as follows: 1. According to the existing research results, the influence of the influence depth of the subgrade working area on the existing tunnel structure is analyzed, the feasibility of the bridge crossing tunnel is obtained, and the structural design of the upper and lower parts of the bridge is carried out according to the specifications. According to the topographic and geomorphological characteristics and geological distribution of the engineering, the 3D mathematical analysis model is established by using ANSYS software, and the influence of pile foundation construction on the structure of existing high-speed railway tunnel is simulated dynamically by FLAC3D software, and the deformation of tunnel structure is obtained. The horizontal displacement law of soil around pile is used to judge the safe state of tunnel. And guide the construction of pile foundation, optimize the monitoring and measurement scheme. 3. According to the results of numerical simulation analysis, combined with the characteristics of the project and the relevant specifications, the monitoring scheme is optimized and arranged, including monitoring items, monitoring means, monitoring points and sections, monitoring frequency and so on. The monitoring data and the numerical simulation results are compared and analyzed to judge the safety condition of the tunnel more accurately. The analysis shows that both of them are consistent in the deformation law of tunnel structure, and the main reason of affecting the deformation of tunnel structure is the distance between pile foundation and tunnel structure.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：U456.3;U445.551

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