随机轮轨力作用下基于2.5维离散支撑模型的轨道垂向振动分析  

Analysis on Vertical Random Vibration of 2.5D Discrete Support Track Model under Wheel-rail Force Effect

作　　者：朱志辉[1,2] 王凡 罗思慧 李奇[3] 蒋丽忠[1] ZHU Zhihui;WANG Fan;LUO Sihui;LI Qi;JIANG Lizhong(School of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Laboratory for High Speed Railway Construction,Changsha 410075,China;School of Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中南大学高速铁路建造技术国家工程实验室,湖南长沙410075 [3]同济大学土木工程学院,上海200092

出　　处：《铁道学报》2021年第6期104-111,共8页Journal of the China Railway Society

基　　金：国家自然科学基金(52078498,51678576,51878501);国家重点研发计划(2017YFB1201204)。

摘　　要：针对轨道随机不平顺引起的钢轨高频振动响应问题,建立2.5维有限元离散支撑轨道动力学实体模型。首先结合高速车辆模型建立耦合系统垂向振动模型,进而基于虚拟激励法得到由轨道不平顺引起的动态轮轨力功率谱;然后基于2.5维离散支撑轨道数值模型,将动态轮轨力功率谱作为激励,得到轨道系统的随机振动响应。通过与格林函数结果对比,验证了本文模型的正确性。结果表明:采用2.5维有限元法及荷载等效法可快速实现无限长离散支撑实体轨道模型全频域计算,可模型钢轨的横截面变形特征;以CRH3型高速动车为例,高于2800 Hz时轨道结构的横截面开始明显变形;低于50 Hz时四个轮对处的振动加速度功率谱密度差别显著;170~3000 Hz内垫板刚度对轨道结构振动加速度影响较大。In view of the high-frequency vibration response of the rail caused by the random irregularity of the track,a 2.5D finite element discrete support track dynamic solid model was established.The vertical vibration model of coupling system was established based on the high-speed vehicle model.The wheel-rail force power spectrum was obtained quickly by using pseudo-excitation method and superposition.Based on the 2.5D discrete support track numerical model,the dynamic wheel rail force power spectrum was used as the excitation to obtain the random vibration response of the track system.By comparing with the results of green function method,the correctness of the model was verified.The results show that the full frequency domain calculation of the infinite length discrete support solid track model can be realized quickly by using the 2.5D finite element method and the load equivalent method,which can model the cross-sectional deformation characteristics of the rail.In the case of CRH3 high-speed EMU,above 2800 Hz,the cross-section of the track structure begins to show significant deformation.Below 50 Hz,the power spectral density of vibration acceleration of the track at the four wheelsets is significantly different.In the range of 170-3000 Hz,the stiffness of the pad has a great influence on the vibration acceleration of the track structure.

关 键 词：离散支撑轨道 2.5维有限元法 随机振动 车辆-轨道耦合系统 虚拟激励法 

分 类 号：U211[交通运输工程—道路与铁道工程]