基于轨道振动理论的梯形轨枕轨道钢轨波磨研究

Study on the Rail Corrugation of the Ladder-type Sleepers Track Based on the Track Vibration Theory

研究半径为350 m梯形轨枕曲线轨道上波磨的成因。借助于现场观察和测量,获得波磨的特征参数。调查区段车辆运行速度在35 km/h左右,该波磨的主波长为60~100 mm,其通过频率为110~180 Hz;次波长为30 mm,其通过频率为324Hz。结合轨道结构振动理论对波磨成因进行预测分析。根据结构特征建立梯形轨枕轨道三维有限元实体模型,利用此模型分析轨道结构的固有特性与波磨通过频率的内在联系,对波磨的成因做出初步解释,利用该模型计算分析白噪声激励下轨道结构的频响特性,进一步揭示波磨形成的机理。将理论计算结果与现场测试数据比较,两者相吻合。研究表明,车辆通过梯形轨枕轨道时,容易引起钢轨相对于轨枕的垂横向弯曲振动,从而加剧轮轨粘滑振动,加速了该轨道曲线段波磨的形成和发展。

The mechanism of rail corrugation on 350 m tight curves of ladder-type sleepers＇ track is investigated.Field observations and measurements are conducted.The characteristics of corrugation are obtained.The dominant wavelength is 60-100 mm and the minor wavelength length is 30 mm.The vehicle speed is approximately 37 km/h.The corrugation-related frequency bands of the dominant and minor wavelength are 110-180 Hz and 324 Hz,respectively.The possible reason of the corrugation is analyzed according to the theory of track structure dynamics.A three dimensional finite element method（FEM） track model is established and it is utilized to analyze the relationship between rail corrugation and model shape and resonance frequency.The preliminary explanation of corrugation formation is obtained.The cause of corrugation is studied according to the response of track under the excitation of white noise.The theoretical results are in good agreement with the field measurements.The obtained results show that the vertical and lateral bending vibration of rail relative to the ladder-type sleepers can be easily excited when the vehicle passes the track.They exacerbate the wheel-rail stick-slip vibration and at last accelerate the formation and development of rail corrugation on curves of this track.