基于环形试验台的钢轨短波长波磨产生机理研究OA北大核心CSTPCDEI
Mechanism of short wavelength corrugation generation on rail based on circular test rig
介绍一种具有小半径曲线轨道的环形试验台,并对其钢轨表面短波长波磨的形成原因进行分析.环形试验台上车辆运行6 000圈后,在低轨表面观察到钢轨波磨以3.31 mm的波长再现.通过力锤敲击对轨道动态特性进行频率响应函数测试,并在行车条件下对波磨附近处高低轨的振动加速度进行数据采样,采用短时傅里叶变换对采样数据在频域上进行分析.根据试验台的实际尺寸建立轨道三维实体有限元模型,并对其进行模态分析和频响分析.结合试验和仿真的结果分析轨道结构动态特性与钢轨波磨的相关性.结果表明,试验车辆运行速度为12 km/h时,3.3 mm波长波磨的通过频率为1 007 Hz.低轨的1阶垂向Pinned-Pinned频率为2 277 Hz,低轨的1阶横向Pinned-Pinned频率为1 015 Hz,与波磨通过频率相吻合.车辆通过小曲线半径时,低轨上的横向振动幅值远大于高轨上的振动幅值,且低轨上的横向Pinned-Pinned频率1 015 Hz容易被激发,形成与共振频率对应的波磨,且在不同行车速度下低轨被激发出来的横向Pinned-Pinned频率几乎不会受速度的影响,振动幅值随着速度的减小依次降低.低轨频率响应函数试验测试的结果和有限元仿真的结果相吻合,验证了所建立的有限元模型的准确性,且在白噪声的激励下,有限元模型中低轨的横向Pinned-Pinned频率极易被激发出来,其模态振型表现为以钢轨弹性扣件支撑点相对固定.轨道结构波磨的产生主要与轨道结构中高频固有特性相关,钢轨横向Pinned-Pinned模态被激发加剧了钢轨的横向振动是导致小曲线半径低轨钢轨波磨形成的原因.
This paper presented a circular test rig featuring a track with a small-radius curve and delves into the formation causes of short-wavelength corrugation on rail surfaces.Rail corrugation with a wavelength of 3.31 mm was observed on the low rail surface after 6 000 laps of vehicular operation on the test rig.The track's dynamic characteristics were assessed using a force hammer for frequency response function tests and by sampling vibration acceleration data on high and low rails near the corrugation under operational conditions.These data were analyzed in the frequency domain using short-time Fourier transform.A 3D solid finite element model of the track,congruent with the test rig's actual dimensions,was developed for modal and frequency response analyses.The correlation between the dynamic characteristics of the track structure and rail corrugation was investigated through a combination of experimental and simulation results.Conclusions are drawn as follows.At a vehicle speed of 12 km/h and a corrugation wavelength of 3.3 mm,the pass-through frequency is 1 007 Hz.The low rail's first-order vertical and lateral Pinned-Pinned frequencies are 2 277 Hz and 1 015 Hz respectively,with the latter aligning with the corrugation frequency.Lateral vibration amplitudes on the low rail significantly surpass those on the high rail when vehicles traverse small-radius curves.The low rail's lateral Pinned-Pinned frequency of 1 015 Hz is readily excited.This can result in corrugation at the resonant frequency.This frequency,and the associated vibration amplitudes,are minimally affected by speed variations,showing a decrease with reduced speeds.The experimental results from the low rail's frequency response function test correspond with the finite element simulation,affirming the finite element model's accuracy.According to the model,under white noise excitation,the low rail's first-order lateral Pinned-Pinned frequency is easily stimulated,exhibiting a modal shape where the steel rail's elastic fastener support points remain relatively static.The generation of rail corrugation in track structure is mainly related to the intrinsic properties of high and medium frequencies in track structures.The activation of the steel rail's lateral Pinned-Pinned mode intensifies its lateral vibrations,contributing to the formation of corrugation on the low rail in small curves.
汪梦寒;顾晓菡;王安斌
上海工程技术大学 城市轨道交通学院,上海 201620上海工程技术大学 城市轨道交通学院,上海 201620||上海轨道交通振动与噪声控制技术工程研究中心,上海 201620
交通运输
小半径曲线轨道环形试验台钢轨波磨轨道结构动态特性中高频固有特性
small radius curve trackcircular test rigrail corrugationdynamic characteristics of the track structuremid-to-high frequency intrinsic characteristics
《铁道科学与工程学报》 2024 (007)
2687-2698 / 12
国家自然科学基金资助项目(52178441);中国国家铁路集团科技研究开发计划项目(L2021G005)
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