Mechanism of short wavelength corrugation generation on rail based on circular test rig
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.
small radius curve trackcircular test rigrail corrugationdynamic characteristics of the track structuremid-to-high frequency intrinsic characteristics
国家科技期刊平台
NSTL
万方数据
