【作者】 徐劲；

【导师】 谢伟平；

【作者基本信息】 武汉理工大学 ， 结构工程， 2002， 硕士

【摘要】 列车在运行时产生的振动会通过周围地层向外传播，并进一步诱发建筑物的二次振动，对建筑物以及其中居民的工作和日常生活产生了很大的影响。如何减小振动造成的环境污染已经成为一个很重要的课题。 要做出正确、适当的环境振动评价，首先要掌握列车运行时振动产生的机理。轨道系统由铁轨、枕木和碎石垫层组成，列车在运行时车轮与轨道系统会产生相互作用，由于轮重的作用使轨道产生弯曲变形，这一弯曲波通过周围地层向外传播。然后轨道的变形转化成作用在地基上的荷载，由此计算地基内波动的产生与传播。 本文基于振动产生及传播的机理，将轨道系统简化为弹性地基梁模型，将运行的列车模拟成一个作用在梁上的移动荷载，以新干线、TGV、在来线以及国内的武汉轻轨等四种轨道系统为研究对象，对移动荷载作用下轨道系统的振动传播模型进行了评价。对于振动在地基中的传播采用分层法的解析算法，得到了地基土在移动荷载作用下的时程分析曲线、加速度变化曲线以及在不同地质条件下的传递函数反应谱等，并对计算结果进行了分析，在实际工程计算当中，这一方法也是广泛被采用的。在考虑轨道系统与地基土的协同工作原理的基础上，本文分别对轨道系统和地基的频率响应特征进行了分析，并和以前所作的研究工作进行了比较，得到了一些有益的结论。对于轨道一高架桥一地基系统，本文采用二次梁计算模型来计算它在移动荷载作用下的动力响应，分析了振动在系统中的产生与传播过程。 最后，在全面总结论文工作的基础上，提出本课题尚待深入研究的若干问题。更多还原

【Abstract】 The train-induced vibration will spread outward through the medium of around strata, and induce the secondary vibration of construction in further, which brings great influence to construction and people’s daily life. How to diminish the environment pollution cased by vibration has become a very important problem.To get right proper evaluation of environment vibration, first of all we should master the mechanism of how the train induced vibration came into being .The track system is composed of rail sleeper ballast and substrate. When the train moves, the wheel and the track system will interact each other. Because of the action of the wheel, the track may bright bent transformation, and the transformation spread in the ground. Then the transformation changes into load which act on the foundation, thereof we calculate the wave’s propagation in the ground.The present paper based on the mechanism of the vibration’s production and transmission, simplifying the track system as elastic foundation beam model, and using a moving load which act on the beam to simulate the train, regarding four sorts of track system as research object, to evaluate the model of the vibration propagating of the track system under the moving load. Using the analytic method of finite elastic layer to calculate the transmission of the ground vibration, we get the displacement-time curve, acceleration-time curve and transfer function spectrum of ground under moving load, and analyze the result. In practice engineering calculation, this method is wildly used. Considering the cooperation of track system and ground, the present paper analyses the frequency response of track system and ground, and compares with the formerly research, getting some useful conclusion. For the track-viaduct-ground system, we use double-beam model to calculate its dynamic response under moving load, and analyze the transmission of the vibration in the system.At last, some problems about this research worth to be studied afterward are put up.更多还原