成灌快铁桥墩处环境振动测试分析

Measurement and Analysis of Environmental Vibration in a Bridge Pier of Cheng-Guan High-speed Railway

为研究桥墩处的环境振动特性,采用现场实测的方法对成灌快速铁路桥墩处环境振动进行测试。分析桥墩处环境振动的时程曲线、频谱曲线数据,初步得出地面竖向环境振动特性,并采用回归分析方法,拟合出竖向振动的衰减公式。结果表明:随着距线路中心距离的增加,振动加速度逐渐减小,地面振动持续时间较短,约为6 s;环境振动在衰减过程中,近振源处的衰减速度大于远振源处的衰减速度;环境振动的能量主要集中在10 Hz^63 Hz之间;桥墩处的竖向环境振动最大值符合指数衰减规律。

In-situ tests are conducted in a bridge pier ground of Cheng-Guan high-speed railway and the environmental vibration characteristic of the pier is preliminarily revealed.By using regression analysis and curve-fitting method,the attenuation formula of vertical vibration is obtained.The results show that the vibration acceleration decreases gradually with the increase of the distance from the center of the track,and the duration of ground vibration is about6s.The decay rate of the environment vibration near the vibration source is greater than that far away from the vibration source.The energy of the environmental vibration is mainly concentrated on in10Hz-63Hz frequency range.The maximum of the vertical vibration of the bridge pier decays in an exponential law.