高速铁路42号无缝道岔温度力分析与焊接顺序优化研究

Research on Temperature Force and Optimization of Welding Sequence of No.42 Welded Turnout in High-Speed Railway

高速铁路大号码无缝道岔内部的焊接接头众多,为满足列车过岔时的高平顺性要求,故对道岔焊接施工过程的温度控制要求较高,增加了高速道岔的施工难度。为进一步提升大号码道岔焊接施工性能,解决大号码无缝道岔内部各轨接头焊接顺序不明的问题,基于有限元法建立42号有砟轨道无缝道岔模型,研究不同焊接顺序对岔区内钢轨及轨枕的受力与变形的影响。结果表明:大号码无缝道岔岔内按基本轨-导轨-心轨的顺序组建道岔整体,基本轨双向对称焊接、导轨按先直后曲、由后至前成对焊接的方案,可有效放散岔区钢轨施工焊连的温度力;对于需铺设于环境温差变化较大地区的大号码无缝道岔,采用本文推荐焊接顺序可将大号码有砟无缝道岔的容许焊接温度限值扩大至5℃,提高大号码道岔的可施工性。

Large-number seamless turnouts in high-speed railway have a lot of welded joints.In order to meet the requirements of high smoothness when the train passes through the turnout,the temperature control requirements of the turnout welding construction process are relatively high,which increases the construction difficulty of the high-speed turnout.In order to further improve the welding construction performance of large-size seamless turnouts and solve the problem of unclear welding sequence of the internal rail joints of large-number seamless turnouts,this paper establishes the No.42 seamless turnout model in the ballasted track model based on the finite element method,and studies the effects of different welding sequences on the stress and deformation of rails and sleepers in the turnout area.Calculation result shows that when the large-number seamless turnout is assembled in the order of basic rail-guide rail-point rail and in the process that the basic rail is welded symmetrically in two directions,and the guide rail is welded in pairs from straight to curved and from back to front,the temperature force of rail welding in turnout area can be effectively dissipated.The welding sequence recommended in this paper can extend the allowable welding temperature limit of large-number ballasted seamless turnout to 5℃and improve the constructability of large-number turnout.