轨道交通中无砟轨道动力模型分析

Dynamic Model Analysis of Ballastless Track Structure in Urban Rail Transit

本文首先对轨道交通中广泛采用的无砟轨道结构的减振特点进行了分析,并在对其结构尺寸分析的基础上,针对预制式轨道板结构的特点,本文建立了预制式浮置板结构的动力分析模型,即结构的刚体振动模型。同时比较了现浇连续型轨道板的梁的振动分析模型,根据无砟轨道轨道板上述两种动力分析模型对计算结果的影响分析,确定了轨道板上述两种动力模型的应用范围:刚体模型在工程中一般适应于预制式无砟轨道结构,当轨道板的长厚比小于或等于25时,其动力模型取为刚体模型;反之,轨道板的长厚比大于25时其动力模型取为梁模型,梁模型一般适应于现浇的无砟轨道轨道板结构。

A coupling dynamic model for vehicle--ballastless track on bridge was derived based on the vehicle-ballastless track--bridge system coupling dynamics to analyze the dynamic performance of the ballastless tracks. In the model, the ballastless tracks with discrete slabs are regarded as the rigid bodies on elastic supports. The dynamic model of ballastless tracks with discrete slabs on the bridge was also derived. In the meantime, this model is compared with the dynamic one of ballastless track with continuous slabs, which is regarded as Bernoulli-Euler Beams on elastic supports. On the basis of difference of calculate results are aroused by the above two dynamic models, the applied range of the above two models is determined in urban rail transit. The model of slabs is regarded as Bernoulli-Euler beams when the ratio of its length and thickness is greater than 25, otherwise, which is regarded as the rigid body.