无砟轨道温度梯度荷载对列车-路基上板式无砟轨道系统动力特性的影响

摘要

在吸收国内外研究成果的基础上,建立能够考虑无砟轨道-路基系统各部件间接触状态非线性的列车-路基上板式无砟轨道三维有限元耦合动力学模型,并对建立的三维有限元耦合动力学模型进行相应验证.运用建立的耦合动力学模型,对列车在路基上板式无砟轨道线路上高速行驶时,在列车荷载和无砟轨道温度梯度荷裁共同作用下,列车-路基上板式无砟轨道耦合系统动力特性进行研究.研究结果表明:无砟轨道温度梯度荷载对列车-路基上板式无砟轨道耦合动力学系统轮轨力特性影响很小,但对无砟轨道各部件动力特性有显著影响,在进行无砟轨道各部件动力特性研究时,有必要考虑无砟轨道温度梯度荷载的不利影响；对于Ⅱ型板式无砟轨道,无砟轨道温度梯度荷载对列车-路基上板式无砟轨道耦合动力学系统动力特性影响与裂缝间距有很大关系,裂缝间距越小,其影响越小.%A vehicle-slab track-subgrade three-dimensional finite element coupling dynamic model which can take the nonlinear contact state of different parts of slab track-subgrade system into account was established based on the domestic and foreign research results,and the corresponding program was developed and verified.With the established dynamic model,by using high-speed trains passing slab track on subgrade as example,dynamic characteristics of train-slab track on subgrade system were theoretically studied under temperature gradient load of slab and train load.The calculated results show that temperature gradient load of slab has little influence on dynamic characteristics of wheel/rail vertical force,but it has significant effect on dynamic characteristics of different components of slab track,so the adverse influence of temperature gradientload cannot be ignored when studying the dynamic characteristics of different components of slab track.For Ⅱ-type slab track the influence of temperature gradient load of slab track on dynamic characteristic of train-slab track on subgrade system is greatly related to crack spacing,and the shorter the crack spacing,the smaller the influence of temperature gradient load of slab track.