基于连续弹性基础梁模型的扣件动刚度测试方法

Test Method of Fastener Dynamic Stiffness Based on Continuous Elastic Foundation Beam Model

为确定服役状态下的轨道扣件动刚度,将钢轨视为置于连续弹性基础上的简支梁,推导扣件动刚度计算式,提出基于连续弹性基础梁模型的扣件动刚度测试方法,对某服役状态下的高铁线路轨道扣件动刚度进行测试。结果表明:扣件动刚度由钢轨1阶弯曲振动的频率和参振长度、钢轨的单位长度质量和抗弯刚度以及扣件的支承间距决定,当轨道结构确定时扣件动刚度可通过测试钢轨1阶弯曲振动频率求得,其计算式在振动频率小于450 Hz时计算结果的误差小于10%;某高铁线路CRTSⅡ型板式无砟轨道服役状态下的扣件动刚度为36.5kN·mm^(-1),约为垫板静刚度的1.62倍。

In order to determine the dynamic stiffness of the track fastener in service,the rail was regarded as a simply supported beam set on a continuous elastic foundation,and the calculation formula of fastener dynamic stiffness was deduced.A test method for the dynamic stiffness of fastener was proposed based on the continuous elastic foundation beam model and the track fastener dynamic stiffness of a high-speed railway line in service was tested.The results show that the fastener dynamic stiffness is determined by the frequency and vibration length of the rail first-order bending vibration,the mass per unit length and bending stiffness of the rail and the support spacing of the fastener.When the track structure is determined,the dynamic stiffness of the fastener can be obtained by testing the first-order bending vibration frequency of the rail,and the error of the calculation formula is less than 10%when the vibration frequency is less than 450 Hz.The fastener dynamic stiffness of CRTSⅡslab ballastless track in service of a high-speed railway line is 36.5 kN·mm^(-1),which is about 1.62 times of the static stiffness of the baseplate pad.