公路隧道结构变形的数值模拟与光纤光栅监测研究

发布时间：2018-05-21 01:40

本文选题：隧道工程 + 结构变形　；参考：《昆明理工大学》2014年硕士论文

【摘要】：随着以公路建设为主的基础设施建设在我国的空前发展,西部地区山岭公路隧道工程数量不断增长,建设速度不断加快,但因地质条件及施工等原因,国内己建或在建的大部分公路隧道都存在不同程度的隧道病害问题。因此,在隧道施工及运营过程中对围岩与支护结构的受力状态进行分析与监测,对隧道可能出现病害的位置准确预警,在保证隧道结构安全及工程质量方面具有重要的作用。本文以云南省田心隧道为研究对象,为确保其施工及运营安全,对围岩与支护结构受力状态进行了有限元数值模拟与现场监测对比研究。主要包括以下几方面的工作： 1.研究分析了隧道施工数值模拟理论及其在ANSYS中的实现。根据田心隧道工程概况,利用有限元法建立其平面应变计算模型,并采用施加虚拟支撑力逐步释放法与单元生死技术模拟台阶法施工过程。 2.分析有限元数值模拟所得围岩位移场、围岩应力场与二次衬砌内力,得出隧道结构变形与受力规律。 3.根据有限元数值模拟结果,确定了光纤光栅监测方案,利用FBG传感器建立了由二次衬砌应变监测子系统与围岩压力监测子系统组成的光纤Bragg光栅传感网,对隧道健康状态进行长期监测。 4.监测数据与模拟结果对比表明,除拱顶二次衬砌应变外,其余位置二次衬砌应变及围岩压力监测值与数值模拟所得隧道受力状态基本一致,应变监测值约为模拟值的60%～70%,围岩压力监测值与模拟值吻合；拱顶应变监测值(309.83με～327.23με)大于应变模拟值(209.37με),与现场拱顶部位开裂现象一致,是长期监控的重点。 5.将数值模拟与现场监测相结合的分析方法应用于隧道工程可准确预警隧道病害位置,克服了单一现场监测方法存在的预见性较弱等缺陷,充分说明该方法在确保隧道施工及运营安全方面是行之有效的。
[Abstract]:With the unprecedented development of the infrastructure construction based on highway construction in China, the number of mountain highway tunnel projects in the western region is increasing and the construction speed is speeding up, but due to geological conditions and construction and other reasons, Most highway tunnels built or under construction in China have different degree of tunnel disease. Therefore, in the course of tunnel construction and operation, the stress state of surrounding rock and supporting structure is analyzed and monitored, and the location of possible tunnel diseases is accurately forewarned, which plays an important role in ensuring the safety of tunnel structure and engineering quality. In order to ensure the safety of construction and operation of Tianxin Tunnel in Yunnan Province, the finite element numerical simulation and field monitoring of surrounding rock and supporting structure are carried out in this paper. This includes the following areas of work: 1. The numerical simulation theory of tunnel construction and its realization in ANSYS are studied and analyzed. According to the general situation of Tianxin tunnel project, the plane strain calculation model is established by using finite element method, and the step method construction process is simulated by applying virtual supporting force step by step release method and element birth and death technique. 2. The displacement field, stress field of surrounding rock and internal force of secondary lining are obtained by finite element numerical simulation, and the deformation and force law of tunnel structure are obtained. 3. According to the results of finite element numerical simulation, the fiber Bragg grating (FBG) monitoring scheme is determined. The fiber Bragg grating sensing network is established by using the FBG sensor, which consists of the secondary lining strain monitoring subsystem and the surrounding rock pressure monitoring subsystem. Long-term monitoring of tunnel health status was carried out. 4. The comparison between the monitoring data and the simulation results shows that the monitoring values of the secondary lining strain and surrounding rock pressure at the other locations, except for the secondary lining strain of the arch roof, are basically consistent with the numerical simulation results. The strain monitoring value is about 60 / 70 of the simulated value, the monitoring value of surrounding rock pressure is in agreement with the simulated value, and the strain monitoring value of arch roof is 309.83 渭蔚 ~ 327.23 渭蔚), which is larger than the strain simulation value of 209.37 渭蔚, which is consistent with the cracking phenomenon at the site of the vault, and is the focus of long-term monitoring. 5. The method of numerical simulation combined with field monitoring is applied to the tunnel engineering to accurately warn the location of tunnel disease, which overcomes the shortcomings of the single field monitoring method such as weak predictability, etc. It is fully explained that the method is effective in ensuring the safety of tunnel construction and operation.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U456.3

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