Development of CounterVibration Measure by Tire Fill-in WIB Method

本研究旨在揭示列车振动从列车到附近地面的传递机理，并在此基础上开发出一种有效的防振措施--带轮胎填充的蜂窝WIB。开展了以下工作。(1)列车和交通振动预测计算机仿真系统的研制考虑移动荷载的影响，对轨道-地面系统进行了动力分析。在求解过程中采用了2.5维解的方法，计算效率高。基于波场知识，推导出蜂窝状波障的基本设计公式。(2)现场测量通过对列车轨道振动的测量，观测到列车轨道振动在地面的传播。并以资料为依据进行了理论解释。现场检测结构振动和地面振动，并与结构固有频率和地面波的频散特性进行比较。(3)现场试验研究了冲击载荷和简谐载荷作用下轮胎填充层的动力学特性。对该措施在桩基附近施工时的减振效果进行了评价。并与计算机模拟结果进行了比较。

This study aimed first at revealing the vibration transmission mechanism from the train to nearby ground, and then at developing effective vibration counter measure called honeycomb WIB with tire fill-in based on the former knowledge. The following works have been conducted. :(1) Development of the computer simulation system for predicting the vibrations induced by train and trafficThe dynamic analysis for a track and ground system is investigated with due consideration of the moving load effect. The 2.5 dimensional solution method is taken for the effective and efficient procedure. The fundamental design formula of a honeycomb wave impeding barrier (WIB) is developed based on the knowledge of the wave field.(2) Field measurementsFrom the vibration measurement along a train track, the vibration transmission from train track through the ground was observed. The theoretical interpretation is made based on the data. The structural borne vibration and the ground borne vibration are then detected in comparison with the structural natural frequencies and the wave dispersion characteristic of the ground at site.(3) Field experimentThe dynamics of the tire fill-in WIB are investigated by the impact loading and harmonic loading. The vibration reduction of this measure is evaluated when it is constructed in the vicinity of a pile foundation. The results are also compared with the computer simulation.