地铁先锋扣件地段钢轨波磨成因

为了研究先锋扣件地段钢轨波磨的成因并给出应对措施，基于摩擦自激振动引起钢轨波磨的理论，建立了包括导向轮对、轨道系统的自激振动有限元模型，使用复特征值法研究了轮对-轨道系统的动态稳定性；通过参数敏感性分析寻找影响钢轨波磨的主导因素，提出抑制乃至消除钢轨波磨的措施. 研究结果表明:轮轨间饱和的蠕滑力引起的轮对-轨道系统频率为319 Hz的自激振动是导致内侧钢轨严重的波磨的主要原因，模型预测的波磨波长为51.4 mm，与实测数据非常接近；参数敏感性分析表明，先锋扣件中的橡胶支承块的弹性模量和阻尼系数越大，钢轨波磨发生的可能性越低；采用弹性模量和阻尼系数有利于抑制乃至消除钢轨波磨，将阻尼系数提高到0.000 1可显著抑制钢轨波磨. 

Formation Mechanisim of Rail Corrugation Occurring on Tight Curved Track with Vanguard Fasteners

In order to study the formation mechanism and countermeasures of the rail corrugation on a tight curved track with vanguard fasteners. First, a self-excited vibration finite element model consisted of the leading wheelset and the track system was established based on the viewpoint of friction-induced vibration causing rail corrugation. The dynamic stability of the wheelset-track system was analyzed using the complex eigenvalue method. Then, the dominant factors affecting the rail corrugation were found through the parameter sensitivity analysis, and the countermeasures to suppress or eliminate the rail corrugation were put forward. The results show that the self-excited vibration of the wheelset-track system at 319 Hz induced by the saturated creep force between the wheel and the rail is the main cause of severe rail corrugation on the inner rail. The corrugation wavelength predicted by the model is 51.4 mm, which is closed to the measured data. The parameter sensitivity analysis shows that the modulus of elasticity and damping coefficient of the rubber rest pad in the vanguard fasteners have a great influence on the rail corrugation, the larger the elastic modulus and damping coefficient are, the lower the probability of rail corrugation occurrence is. The rubber rest pad with high modulus of elasticity and damping coefficient is beneficial to the suppression or even elimination of the rail corrugation. when the damping coefficient of the rubber rest pad is above 0.000 1, the rail corrugation can significantly be alleviated.