成灌快铁桥墩处环境振动测试分析

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。

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

In-situ tests have been conducted on the bridge pier ground and preliminary revealed the environmental vibration characteristic of Cheng-guan high-speed railway. By using regression analysis method, the attenuation formula of vertical vibration is fitted. The results shows that the vibration acceleration decrease gradually with the increase of the distance from the center of the line and the duration of ground vibration is about 6s.Secondly, the decay rate of the near source attenuation speed is greater than the far source and the energy of environmental vibration is mainly concentrated in 10-63 Hz. Finally, the max vertical vibration value of the bridge pier is in accordance with the exponential decay law.