成渝高速铁路某路堤段地面三向振动测试分析

为研究高速铁路路堤段地面振动的传播和衰减规律,选择成渝高速铁路某路堤段进行现场地面三向振动测试。在时域和频域内分析地面三向振动的时程特征和频谱特征,以及垂向振动、水平向振动随距离的传播特性。结果表明,在距离线路纵向中心线同一距离处,横向(Y)、纵向(X)振动加速度最大值及有效值均大于垂向(Z),随距离的增加,加速度最大值及有效值均呈衰减趋势;随着距离的增大,三向振动的频率带宽均越来越窄,远场垂向和纵向振动主频均基本集中在33.6 Hz左右,横向优势频率集中在9.6 Hz。计权后的垂向振级高于水平向振级,未计权的水平向振级均大于垂向振级,未计权三向加速度级和计权三向振级随距离的传播近似符合负指数规律。

Tri-axial vibration measurements and analysis of the high-speed train induced ground-borne vibration on embankment of Chengdu-Chongqing high-speed railway

Ground-borne vibration is one of the major environmental problems generated during the operation of high-speed railway.This work tested the three-dimensional ground-borne vibration of an embankment section of Chengdu-Chongqing high-speed railway for the purpose of investigating the propagation and attenuation characteristics.This study analyzed the time and spectrum characteristics of the three-dimensional ground-borne vibration in the time and frequency domain,as well as the propagation of lateral(Y)and longitudinal(X)vibration and vertical(Z)vibration as a function of distance.The value of maximum acceleration and effective acceleration attenuated with increasing distance,while greater values of maximum acceleration and effective acceleration were obtained from lateral(Y)and longitudinal(X)vibration than from vertical(Z)vibration at the same distance from the longitudinal center line of the embankment.The frequency width of the three-dimensional vibration narrowed with the increase of distance,where in the far field the value of main frequency of the vertical and longitudinal vibration was around 33.6 Hz,and the value of lateral vibration was approximately 9.6 Hz.The unweighted horizontal vibration level was greater than the vertical unweighted vibration level,however,weighted vertical vibration level was greater than the weighted horizontal vibration level.The propagation of unweighted and weighted vibration level with distance approximately follows the negative exponential law.