板式无砟轨道钢轨共振特性影响参数敏感性分析

为研究无砟轨道钢轨pinned-pinned共振影响因素,基于周期性支撑梁结构振动计算理论,建立板式无砟轨道振动实体有限元模型,采用单参数敏感性分析方法,分析了无砟轨道结构参数对钢轨pinned-pinned共振特性的影响,并计算了各参数的敏感度系数.研究结果表明:扣件间距的改变会引起钢轨pinned-pinned共振特性的明显改变,属于敏感参数.钢轨类型对钢轨pinned-pinned共振频率的敏感度系数相对较小,但仍在较敏感范围内.扣件刚度、阻尼及轨道板弹性模量对钢轨pinned-pinned共振频率几乎没有影响,属于不敏感参数.在钢轨表面附加约束阻尼结构会降低钢轨共振振幅,但几乎不改变钢轨的共振频率.受扣件间距的影响,无砟轨道钢轨pinned-pinned共振频率低于有砟轨道钢轨.

Sensitivity Analysis of Influence Parameters on Resonance Characteristics of Ballastless Track Rail

In order to study the influence factors on the pinned-pinned resonance of ballastless track rail, in this paper, based on the vibration calculation theory of periodically supported beam, the influence parameters of ballastless track on the pinned-pinned resonance of rail were analyzed by using the solid vibration analysis model established by FEM, and the sensitivity coefficients of those parameters were calculated through the single-dimensional sensitivity analysis method. The results show that the pinned-pinned resonance of rail is sensitive to the fastener span as the resonance frequencies vary remarkably with the increase of fastener span. Rail mass is a slightly sensitive parameter to the pinned-pinned frequency of rail, although its sensitivity coefficient is smaller than that of fastener span. The stiffness, damping of fastener and elastic modulus of track slab are all classified as insensitive parameters since they have little influence on the pinned-pinned frequency of rail. The constrained damper attached to the non-working surface of rail can reduce the vibration amplitude of the pinned-pinned resonance effectively, but hardly change the resonance frequencies. With the influence of fastener span, the pinned-pinned frequency of rail on ballastless track is lower than that on ballasted track.