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

由于使这些高架桥成为振源的振动是附近3-5赫兹的低频振动，所以它在远距离传播时会在房屋内引起共振现象，在软弱地基上不做距离衰减就会引起故障。通过模型试验和数值模拟分析，明确了地面振动的远距离传播特征。在模型试验中，考虑到模型与实桥的相似规律，将其设置在实桥1/100比例尺的桥头48 cm处。与用模型通过激发机会进行激发实验的结果相比，接近期望值的值可以得到它，并且可以证实与真实事物几乎可以重现的现象。并对房屋的振动因素进行了二维有限元数值模拟分析。通过对5.8赫兹的地面模型进行分析，发现在适用的13.5赫兹的地面上，容易传播的振动个数为1^lt；st；st；对于在波动传播路径中阻断这种地面振动的对策方法也进行了研究。设计了混凝土与EPS复合墙体和废旧轮胎作为隔震墙材料的隔震墙，并进行了现场试验和室内试验。通过它面对地面在低频阶段的振动，成为本研究的目标。

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.