凹形竖曲线上梯形轨道的稳定性研究

为了研究凹形竖曲线上梯形轨道的稳定性,以某城市轨道交通线为例,建立梯形轨道在凹形竖曲线上的叠合梁模型,计算分析在温度荷载、列车垂向荷载和制动力作用下,梯形轨道在凹形竖曲线上的力学特性以及扣件纵向阻力和缓冲垫刚度对轨道结构受力和变形的影响规律。计算表明:由于凸挡台的限位作用,轨道结构在竖曲线上较为稳定;扣件的纵向阻力对钢轨的纵向位移影响较大,为限制钢轨的纵向位移可适当增加扣件的纵向阻力;凸挡台缓冲垫刚度的提高能有效控制钢轨的纵向位移,但会减小缓冲作用,故应合理控制缓冲垫的刚度。

Study on the Stability of Ladder Track on Concave Vertical Curve

In order to analyze the stability of ladder track on the concave vertical curve,the paper refers to an urban rail transit to establish the folded beam model of ladder track on the concave vertical curve,analyze the dynamic characteristics of ladder track under temperature load and braking force and investigate the influencing laws of fastener longitudinal resistance and buffer stiffness to the force and deformation of track structure. The result shows that: due to the positive stop of the convex retaining platform,track structure on the concave vertical curve is stable. As the influence of fastener longitudinal resistance to the displacement of rail is very great,the longitudinal displacement of rail can be restricted by increasing the longitudinal resistance of the fastener as required. By increasing the stiffness of buffer,the longitudinal displacement of rail can be effectively decreased,but buffering effort may be reduced.Thus,the stiffness of buffer needs to be properly controlled.