Analysis Of Longitudinal Temperature Stress And Displacement Of Seamless Single Turnout Of Non-ballasted Track On Bridge

Seamlessly turnout of non-ballasted track on bridge switch not only a combination of ballasted track, CWR track as well as long-span bridges and other technical characteristics, but also spawned a new series of technical problems, that is another major technical challenges facing the rail engineering. Therefore, seamlessly turnout of non-ballasted track on bridge switch technology to become a major focuses on conten for railway institutions at home and abroad as well as the railway sector. Theoretical calculation and analysis of the seamlessly turnout on bridge structure,come to the various influencing parameters on the structure of the law and given a reasonable parameter range,it is of great significance to the design and construction of seamlessly turnout of non-ballasted track on bridge.In this paper, the ANSYS finite element software was used to establish a finite element model of18th single seamless turnout on the simple beam bridge, rail use beam element to simulate, range lines and rail fastener resistance using a linear spring element simulation, rail fastener in turnout area use the nonlinear spring element to simulate, limit stopper use the nonlinear spring element to simulate, spacing iron use a linear spring element to simulate, orbital plate use solid element to simulate, convex block use linear spring element to simulate, the concrete base use solid element to simulate, the bridge plate use solid element to simulate, supports use solid element to simulate,bridge piers use solid element to simulate. Imposed Longitudinal temperature force load and calculation, calculation results were compared with national experts’ calculate results, the force and displacement variation of the basic track is similar with the results of experts, verify the correctness and reliability of the proposed model.By the ANSYS finite element model,the following works are done in this article:(1)Analysis longitudinal force and deformation of18th a single seamless turnout structure on the simple beam bridge in the temperature loads, come to the force and deformation of the seamless turnout on bridge.(2)By calculate the operating conditions1to5, the analysis of the impact parameter for the rail temperature change rate、the fastener stiffness、the convex block stiffness、supports stiffness and bridge span length, obtained the various components force and deformation of the turnout on bridge in the action of these factors affect.Through the calculation and analysis of each impact parameter to draw the following conclusions:(1)The rail temperature change rate have significant impact on single seamless turnout on the simple beam bridge, so a reasonable set of rail locking temperature is required in the construction process of the actual track laying. Line conditions, turnout structures, rail temperature changes rate and other factors should be considered to determine the reasonable limit picture-block gap. To reduce the additional temperature force of the basic track, the limit stopper should be avoided to laying near the beam slit in the actual laying.(2)The basic rail of the seamlessly turnout of non-ballasted track on bridge is in a fixed area, less affected by the fastener stiffness, but Small stiffness of fastener will makes switch rail and heart rails have a greater displacement of telescopic, at the same time spacing iron and limit stopper have a larger force, this will be pass to the basic track a large additional temperature force, therefore, in conditions that ensure the rail strength, using the large stiffness of fasteners is more beneficial for the force and displacement of seamless turnout. But in the actual construction process, or to consider the overall structural strength and stability, select the appropriate type of fastener.(3)The stiffness of convex block has little effect on seamless turnout on bridge, through this calculation compared, the stiffness of convex block suitable around in600kN/mm.(4)Support stiffness changes has little effect on seamless turnout on bridge, select the appropriate supports stiffness should be considered in the actual construction process.(5)Simply supported beam bridge span length is longer, the greater influence will be effect on the force and deformation of the entire structure, but the bridge span length can not be unlimited reduce in the actual construction, a reasonable bridge span length should selected according to the actual situation.