高速铁路温度场作用下桥上无缝道岔与桥梁相互作用研究

Interaction between Seamless Turnout and Bridge of High Speed Railway under Temperature Field

采用通用有限元软件MIDAS/CIVIL建立郑西客运专线渭南北站桥上单开和渡线无缝道岔—桥梁有限元模型,研究温度场作用下无缝道岔与桥梁的相互作用。结果表明:在温度荷载作用下,单开道岔和渡线道岔区钢轨的纵向位移远大于横向位移,最大横向位移约为1~2mm,最大纵向位移约为20~30mm,但均小于钢轨位移允许限值40mm;单开道岔和渡线无缝道岔区钢轨的最大温度纵向力分别为1 303和1 340kN,均发生在连续梁梁缝附近约20m范围内,因此应加强该区域钢轨的监测和养护,防止出现夏季胀轨、冬季断轨的现象,且建议在梁缝处适当减小扣件阻力;单开道岔和渡线道岔区梁体的横向位移非常接近且均较小,最大值分别为2.7和2.8mm,但梁体的纵向位移差异较大,最大值分别为5.3和26.8mm,且均发生在梁端部;无缝道岔区钢轨的温度变形对桥梁的纵向和横向位移影响均很小,梁体均匀温升是引起梁体变形的主要原因,因此桥梁的养护维修可不必过于关注道岔区温度力的影响。

Taking the following two examples,the multi span continuous bridge in two ends of XinWeiNan Railway Station in Zheng-Xi passenger dedicated line and seamless turnout on variable width bridge,we use general finite element software MIDAS/CIVIL to establish finite element model of single and crossing line seamless turnout and bridge on Weinan North Railway Station bridge.The Interaction of seamless turnout and bridge under the action of temperature field is studied.Results illustrate that under the action of temperature load,the longitudinal displacement of single and crossing line turnout rail is much larger than the transverse displacement.The maximum lateral displacement is between 1to 2 mm and the maximum longitudinal displacement is between 20 to 30 mm,but both of them are less than the rail displacement allowed value of 40 mm,having a large residual quantity.The maximum temperature longitudinal force of single and crossing line turnout rail is 1 303 and 1 340 kN,all occur in 20 mrange near continuous beam crevice.So,regional monitoring and maintenance should be strengthened in order to prevent the rail expansion in summer and rail breakage in winter.A proper reduction of fastening resistance in beam crevice is advised.The transverse displacement of single and crossing line turnout beam are very close and smaller,the maximum values are 2.7and 2.8mm.Their longitudinal displacement has large difference,the maximum values are 5.3and 26.8mm,which are all located at beam end.The rail temperature deformation of seamless turnout has little influence on longitudinal,transverse displacement of bridge.The deformation of bridge is caused by the beam average temperature rise.In conclusion,the influence of temperature force of turnout should not be focused too much in bridge maintenance and repair process.