重载铁路列车运行诱发场地振动特性的测试与分析

Testing and Analysis of the Vibration Characteristics of the Site Induced by the Operation of Heavy-haul Freight Trains

为了研究重载列车在路基段运行诱发的地面振动传播与衰减规律,本文通过现场实测得到了不同车型、不同车速的列车通过测试区时,地面不同距离测点的三个方向的振动数据,分析测点振动速度的幅值、振级与频谱特性,得到了地面振动与车速、轴重、振源距离之间的关系。研究发现,近轨7.5m处的竖向振动呈现宽频特征,随着距离增加,50Hz以上的高频振动迅速衰减,对比不同方向的振动,竖向振动随距离衰减呈现明显的幂函数特征,14m以后衰减相对缓慢,而纵向振动呈线性衰减,且振动随距离衰减的过程中存在局部放大现象。车速和轴重对峰值振动速度均有较大影响,振动随车速、轴重的增大而增大。

In order to study the propagation and attenuation law of ground vibration induced by the operation of heavy-haul trains in roadbed section,the vibration data in three direc-tions of ground measurement points at different distances was obtained through field test,when the different vehicle type and speed trains pass through the testing area.The ampli-tude,level,and frequency characteristics of the vibration velocity were analyzed,the relation-ship between ground vibration and vehicle speed,axle load,and the distance to the vibra-tion source was obtained.The test results show that the vertical vibration at 7.5m near the railway track exhibits broadband characteristics,and as the distance increases,the high-fre-quency vibration above 50Hz attenuates rapidly.Compared with vibrations in different direc-tions,the vertical vibration exhibits obvious power function characteristics with distance de-cay,and the attenuation is relatively slow after 14m,while the longitudinal vibration attenu-ates linearly,and there is local amplification in the process of vibration attenuation with dis-tance decay.The vehicle speed and axle load have great effects on the peak vibration speed,and the vibration increases with the increase of vehicle speed and axle load.