【作者】 刘强；

【导师】 施成华； 彭立敏；

【作者基本信息】 中南大学 ， 土木工程， 2014， 硕士

【摘要】 随着我国地铁建设快速发展,已经运营地铁里程逐年增加,地铁隧道服役时间逐渐增长。长期的高密度行车运行,以及修建过程中存在的一些初始缺陷,地铁隧道不可避免的会出现一系列的病害问题,影响其正常使用功能,严重的将危及行车安全。为了满足规范中设计使用寿命100年的要求,开展地铁隧道管片疲劳寿命预测显得尤为重要。本文依托国家重点基础研究发展计划973项目(2011CB013802),运用数值计算方法,对盾构隧道管片及接头动力响应规律及其疲劳寿命预测问题进行了深入研究。主要研究内容及成果如下：(1)分析了结构疲劳破坏发生的机理,详细介绍了常用的疲劳寿命分析方法,归纳总结了已有的疲劳累积损伤理论以及应力-寿命曲线(S-N)确定了适合于盾构隧道的疲劳寿命预测方程。(2)针对地铁盾构隧道管片结构形式,结合隧道-围岩体系振动理论,建立不同埋深错缝拼装的盾构隧道管片精细化模型。从竖向位移、竖向加速度、动应力三个方面分析了列车振动在盾构隧道管片环向的传递规律,明确了衬砌受列车振动影响较大部位。同时分析了不同埋深情况下衬砌结构不同部位动应力响应变化规律。(3)建立基底出现脱空的盾构隧道计算模型,分析了不同基底脱空范围对衬砌结构不同部位动应力响应的影响规律及其受影响程度,并将其与埋深造成的影响进行对比分析。(4)应用疲劳寿命分析软件,对不同埋深、不同基底脱空条件下,盾构隧道疲劳危险部位进行了寿命计算与分析,根据设计寿命要求,对结构是否满足要求进行了判断。更多还原

【Abstract】 With the rapid development of subway construction in China, the operating mileage keeps increasing every year with its service time increasing gradually. Because of long-term high-density operation, and some initial imperfections in the construction, a series of subway tunnel diseases will appear inevitably, affecting the normal use function, and even the running safety when seriously. In order to meet the requirements for the useful life of100years, prediction of fatigue life of the subway tunnel will be particularly important. According to the long-term service lifetime of subway shield tunnel, this dissertation is granted from the National Basic Research Program of China (973:2011CB013802), the dynamic response rule of the shield tunnel under different formation conditions is analyzed, and also the fatigue lifetime of the fatigue dangerous position is predicted by using numerical calculation method. The main research contents and conclusions are as follows:(1) The mechanism of structural fatigue damage is analyzed, some common methods of fatigue lifetime analysis are introduced, the existing fatigue cumulative damage theory and stress-life curve (S-N curve) are summarized, and the prediction equation of the fatigue time suitable for this paper is determined.(2) For the structure of the shield tunnel segment, combining with tunnel-surrounding rock system vibration theory, shield tunnel segment detailed models with different depth under the staggered assembling are built. The law of the train vibration propagation in lining direction is analyzed from vertical displacement, vertical acceleration and dynamic stress. The position greatly influenced by vibration is defined. And the change rule of dynamic response at different part of the lining structure under different depth.(3) When the basement void appears, the influence law and its degree of dynamic stress response of different part in the lining structure affected by void range are analyzed, and comparison analysis with the influence of depth is made.(4) For different depth and condition of basement void, the fatigue lifetime in the dangerous part of shield tunnel is calculated and analyzed by Fe-Safe. According to the requirement of the lifetime, and whether the structure meets it is estimated.更多还原