研究目的:特大跨钢桥在荷载作用下有竖向位移大、自振频率较高的特点，轨道结构的选型直接影响到大桥自身的安全及列车的正常运营，本文通过对国内外钢桥轨道结构选型的介绍，结合渝黔铁路新白沙沱长江特大桥自身的特点，分析轨道结构与钢桥的适应性，确定该桥合理的轨道结构型式。研究结论:(1)有砟轨道结构通过道砟厚度的微调能较好的适应新白沙沱长江特大桥钢桁桥自身以及轨道二期恒载引起的变形大的特性;(2)有砟轨道的碎石道床与该桥车桥振动时的受力特性清晰，也能够更好的适应钢桁桥自振频率高的特性;(3)有砟轨道轨道成熟和稳定的技术更有利该桥钢桁桥的建造和维护;(4)本研究成果在大跨、重载铁路钢桁桥的轨道结构选型上具有一定的参考价值。

Research purposes:Whether the reasonable track structure is adopted or not on large span steel bridge affects directly the normal running of train because a large vertical displacement and greater natural vibration frequency under loads. This paper introduced main track structure types at home and abroad, took new Baishatuo Yangtze River Bridge of Chongqing-Guiyang Railway for example, systematically analyzed the adaptability of track structure and steel bridge, determined reasonable track structure of the bridge.
Research conclusions:(1)The ballasted track structure can better adapt the deformation of steel bridge and deformation caused by the track dead load on New Baishatuo Yangtze River Bridge of Chongqing-Guiyang Railway.(2)The track ballast bed and the mechanical characteristics of the bridge axle vibration is clear, which can also better adapt the characteristics of high natural vibration frequency of the steel bridge.(3)Ease of construction and maintenance comes from the mature and stable technology of the ballasted track structure.(4)The results in this paper has a certain reference value on the selection of track structure on large span or heavy haul steel bridge.