目的 研究高速铁路波磨激励下的轮轨瞬态响应。方法 建立了高速铁路轮轨系统瞬态滚动接触有限元模型，提出了一个改进的轮轨瞬态滚动接触模拟方案，改进的方案采用混合拉格朗日/欧拉方法在静态分析中为轮对施加转速，获得稳态滚动接触解，可以避免传统方案在动态分析中施加转速引起的强烈初始扰动。基于该模型研究了高速铁路钢轨波磨激励下轮轨垂向力、纵向力以及接触斑内应力的变化特征，并讨论了波磨波长和波深对轮轨瞬态响应的影响。结果 当速度提高到500 km/h时，轮轨接触解稳定所需的动态松弛区长度仅为1 250 mm。轮对以300 km/h的速度滚过65 mm的波磨时，轮轨垂向力和纵向力振动频率相同，但相位存在差异。在轮对通过波磨波峰和波谷之间的位置时，接触斑中心向靠近波磨几何一侧转移。波长为65 mm的波磨深度增长到105 μm时，轮重减载率为0.65。波磨波长为65 mm和125 mm时，轮轨垂向力和纵向力均呈现单波长特征。结论 改进的模拟方案在较短的动态松弛区内即可获得稳定的接触解;波磨会激起强烈的轮轨动作用力;波磨深度越大，激发的轮轨动作用力越强烈。垂向力和纵向力峰谷值与波磨深度成线性关系。波磨波长与轮轨力振动幅值不存在简单的线性关系。

Rail corrugation is the undulating wear on the surface of the rail, which has a fixed wavelength at a certain speed and will bring vibration and noise problems to the train-track system, resulting in the failure and shedding of system components and seriously affecting the safety and comfort of train operation. At present, the most effective measure to control rail corrugation is rail grinding. Determining the grinding limit of rail corrugation is the key to formulating an economical grinding strategy and implementing a grinding plan. Determining the grinding limit requires a systematic and in-depth study of the transient response of the wheel-rail system under rail corrugation excitation. The dynamic response of vehicle-track system under rail corrugation excitation is mainly studied by two methods of vehicle-track system dynamics model based on multi-body system dynamics theory and wheel-rail transient rolling contact model based on finite element. However, most of the vehicle-track system dynamics models based on the multi-body system dynamics theory assume that the wheel-rail contact is steady-state, which cannot consider the effect of the real wheel-rail contact geometry, and the wheel-rail contact is unsteady under the rail corrugation excitation. The traditional transient rolling contact model of the wheel-rail system based on finite element has a large initial disturbance and a long dynamic "relaxation zone", which further increases the element law of the model. A transient rolling contact model of the wheel-rail system of high-speed railway was established. An improved simulation scheme for the wheel-rail transient rolling contact was proposed, in which the rotation speed of the wheelset was applied in a static analysis based on mixed Lagrangian/Eulerian description to obtain the steady-state contact solutions. The improved method could avoid the initial disturbance caused by applying the rotation speed to the wheelset in a dynamic analysis. Based on the improved method, the variation characteristics of the wheel/rail vertical force, the longitudinal force and the stresses in the contact patch under the excitation of rail corrugation were studied. The effect of the wavelength and depth of rail corrugation on the transient response of the wheel-rail system was discussed. The improved method could provide a stable contact solution at the expense of a shorter dynamic relaxation zone. When the speed increased to 500 km/h, the required length of the dynamic relaxation zone was only 1 250 mm. Corrugation aroused strong wheel-rail dynamic interaction and the vertical and longitudinal wheel/rail force vibrated at the same frequency but with a phase difference. When the wheelset passed through the position between the crest and the trough of the corrugation, the center of the contact patch shifted to side close to the corrugation geometry. The deeper the corrugation, the stronger the dynamic wheel/rail forces. The peak and valley values of the vertical and longitudinal forces have a linear relationship with the corrugation depth. When depth of the corrugation with a wavelength of 65 mm increases to 105 μm, the wheel load reduction is 0.65. There is no simple linear relationship between the wavelength of the corrugation and the amplitude of the dynamic wheel-rail forces. Under the excitation of the corrugation with the wavelength of 65 mm and 125 mm, the vertical and longitudinal wheel-rail forces show the characteristics of single wavelength.