The elucidation of the long-distance spread mechanism of a low frequency ground vibration to originate in the elevated road

它在长距离内传播，并且在房屋中引起共振现象，并且在软土地基中引起麻烦而不进行距离下降，因为使这些高架桥成为发生源的振动是3- 5 Hz附近的低频振动。本研究从模型试验和数值模拟分析两方面考虑，明确了地面振动的远距离传播特性。考虑到模型与真实的物的相似规律，模型试验中设置在实桥1/100缩尺的48 cm桥头处。利用激励时机对模型进行激励实验，可以得到比期望值更接近期望值的值，可以证实与真实的事物几乎可以再现一种现象。并对房屋的振动因素等进行了二维有限元数值模拟分析。通过<st>对建立在5.8Hz的2阶振型下的地基模型进行分析<nd>，发现在适用的地基中，13.5Hz的1阶振型是最容易传播的振型数。至于在波动传播路径中中断这种地面振动的对策方法，也进行了研究。设计了一种以混凝土、EPS和废旧轮胎为主要材料的复合墙体作为隔震墙体，并进行了局部试验和室内试验。通过对低频阶段的地面振动的研究，使其成为本研究的对象。

It spreads in the long distance, and resonance phenomenon is caused in the house, and causes a trouble in soft ground without doing a distance decline because the vibration which makes these elevated bridges a source of occurrence is the vibration of the low frequency in the neighborhood 3-5Hz. A consideration was done from the model experiment and the numerical simulation analysis by this research to clear the long-distance spread character of the ground vibration. It was set at a bridge head 48cm of 1/100 scale of the actual bridge in the model experiment in consideration of similar rule of the model and the real thing. The value which was close to the desired value than the result that exciting experiment was done with model by exciting opportunity could get it, and it could confirm that a phenomenon with the real thing could be almost reproduced. Furthermore, it is analyzed about the vibration factor of the house and so on two dimensional FEM numerical simulation analysis. It found that it was the number of vibration to spread easily in the applicable ground 13.5Hz with the 1^<st> mode by the analysis with the ground model set up in 5.8Hz the 2^<nd> mode. As for the countermeasure method as well which interrupted such a ground vibration in the spread route of the wave motion, it was examined. The isolation wall which a composition wall with concrete and EPS and a scrap tire were used for was devised, and a local experiment and an indoor experiment were done as a material of isolation wall. Through it faced the ground vibration in the low frequency stage being made the target by this research.