弹性支承块式无碴轨道振动分析新模型

针对弹性支承块式无碴轨道结构特点,提出了一种新的用于竖向振动分析的有限元模型。在该模型中,钢轨模拟为弹性点支承Euler梁;钢轨下面的支承块视为刚体;轨道板视为弹性薄板,并且采用横向有限条与板段单元法对其进行位移插值;钢轨扣件模拟为线性弹簧和阻尼器;轨道板和混凝土底座下的路基模拟为连续分布面弹簧和阻尼器。在此基础上,基于弹性系统动力学总势能不变值原理和形成系统矩阵的"对号入座"法则,推导了弹性支承块式无碴轨道的竖向振动总势能,为建立弹性支承块式无碴轨道竖向振动方程,乃至进行弹性支承块式无碴轨道在高速列车作用下的动力响应分析奠定了良好基础。

New model for vibration analysis of low vibration track

In view of the characteristics of low vibration track(LVT),a new kind of finite element model for vertical vibration analysis was proposed.In this model,rails were regarded as Euler beams on discrete elastic supports,blocks under rails as rigid bodies,and track slabs as elastic plates.By use of the lateral finite strip and slab segment element method,the displacement mode of the slab was obtained.Rail fasteners were considered as linear springs and dampers,and the subgrade under track slabs and concrete roadbeds as planar linear springs and dampers.On the basis of the principle of total potential energy with stationary value in elastic system dynamics and the rule of "Set-in-right-position" for formulating system matrixes,the total potential energy of vertical vibration of LVT was derived.The results show that it can lay the good foundation for further researches such as establishment of vertical vibration equation set of LVT and dynamic response analysis of LVT subjected to high-speed train.