轮轨摩擦自激振动引起小半径曲线钢轨波磨的瞬态动力学

A Transient Dynamics Study on Wear-type Rail Corrugation on a Tight Curve due to the Friction-induced Self-excited Vibration of a Wheelset-track System

钢轨波磨问题一直困扰着地铁线路,对其产生机理的研究有着重要的理论和应用价值。基于轮轨摩擦自激振动引起钢轨波磨的观点,建立轮对稳态通过小半径曲线时由轮对-钢轨-轨枕组成的轮轨系统有限元弹性振动模型,在模型中假设轮轨蠕滑力饱和且等于法向力与摩擦因数的乘积。应用有限元软件ABAQUS分析该模型的运动稳定性,重点研究轮轨系统摩擦自激振动的瞬态动力学过程,获得了轮轨系统发生摩擦自激振动时轮轨振动和接触法向力的变化规律。结果显示内轮和内轨接触摩擦副发生严重的摩擦自激振动,并对这个摩擦自激振动引起钢轨波磨的机理进行了解释。

Rail corrugation has been perplexing metro tracks over the years.It is of great significance in both theory and application to study the generation mechanism for rail corrugation.Based on the viewpoint of friction-induced self-excited vibration of a wheelset-track system causing rail corrugation,an elastic vibration model of a wheelset-track system when a vehicle negotiates a tight curve at a steady state is established,which includes a wheelset,two rails and a series of sleepers.In the model,the creep forces between the wheels and rails are assumed to be saturated and equal to the normal contact forces multiplied by the friction coefficient.The motion stability of the model is analyzed and transient dynamics of friction-induced self-excited vibration of the wheelset-track system is simulated using ABAQUS package.Dynamic vibrations of the rails and time histories of the contact normal forces are obtained due to self-excited vibration of the wheel-track system.Results show that there is a serious fluctuation of the contact normal force between the inner wheel and low rail.The mechanism for the fluctuating contact normal force causing rail corrugation is discussed.