城市交通诱发地面振动测试时域分析

针对日益严重的城市交通所引起的环境振动问题,主要基于广州火车站附近高架路诱发沿线地面振动的现场实测,并包括动车组通过时的测试,通过对实测数据进行深入分析,总结出高架路诱发环境振地的传播规律,在最小二乘准则条件下,提出了更加符合环境振动实际传播特征的衰减经验公式。分析结果表明:竖向振动幅值高出水平向较多,在评价环境振动时,应以竖向振动为主;高架路诱发环境振动和动车组诱发环境振动均呈现脉冲响应特征;高架路诱发环境振动随距桥墩距离增加,脉冲响应特征快速消失,而动车组诱发环境振动的这个特征则相对不明显;存在局部振动放大区域;相比传统经验衰减公式,本文提出的环境振动经验衰减公式更能反映实际环境振动波的传播特点。

In Situ Measurement and Analysis for Environmental Vibration Induced by Urban Traffic in Time Domain

To study increasingly severe vibrations problem induced by urban traffic,field tests of ground vibration were carried out nearby an elevated bridge at GuangZhou railway station,including during a train-set moving.Based on the test data,the propagation laws of environmental vibration were summarized.The mathematical statistics method under the criterion of least-squares was employed to establish the empirical attenuation formula of vertical ground vibration.It is shown that the vertical ground vibration amplitude is much higher than the horizontal one.So the vertical vibration is the most insignificant aspect on evaluation the environmental vibration on ground.The ground vibration induced by the elevated bridge and the train-set all have the characteristic of impulse.Compared to the ground vibration induced by train-set,the characteristics of impulse for ground vibration induced by elevated bridge disappeared more quickly.There is a local amplification region when the vibration induced by urban traffic propagates.Compared to the traditional empirical attenuation formula of ground vibration,the empirical attenuation formula proposed by the author can reflect the actual attenuation characteristics of the ground vibration induced by urban traffic.