齿轨铁路设计规范编制中桥梁荷载取值研究

齿轨铁路是登山旅游轨道交通适宜的方式,国外已有多处建成实例,我国在此区域仍属空白。齿轨铁路建设需要编制设计规范,桥梁荷载取值是规范编制的重要研究环节。通过对齿轨及轮轨系统分析,大坡度齿轨荷载取值可参照现有轨道交通规范。在桥梁荷载一节,根据齿轨的大坡度以及轨道制式不同,按动态和静态状况进行比较分析,得出结论:(1)大坡度不会导致恒载、活载等产生额外的水平分力,不会对桥墩构造尺寸造成影响,但列车牵引制动力会增大,列车性能需要提高;(2)轮轨及齿轨的轨道制式不同,齿轨桥梁荷载的牵引制动力不能简单参照现行轨道交通规范中竖向力的10%～15%考虑,应大于此数值;(3)离心力与牵引制动力叠加时,不应对牵引制动力进行折减;(4)冲击系数及横向摇摆力国内研究较少,从齿轨与轮轨的异同点出发,对齿轨上可能导致参数变化的各种因素进行定性分析。

Study on Bridge Load Value in Compiling Design Code for Rack Rail

Rack rail is a suitable way for mountaineering tourism rail transit. There have been many operating rack railways abroad, but it is still absent in China. To construct a rack railway, design specifications need to be compiled, and the selection of bridge load is important part in the compilation of specifications. Through the analysis of the rack railway and the wheel-rail system, the load value of the rack rail with heavy grade can refer to the existing rail transit specifications. In the section of bridge load, the paper conducts a comparative analysis in terns of dynamic and static conditions according to the differences in the heavy grade and track system, and draws the conclusion that:(1) heavy grade will not cause additional horizontal forces such as dead load and live load and will not affect the pier structure size, but the traction braking force of the train will increase, and the train performance needs to be improved;(2)The traction braking force of rack rail bridge load cannot be considered simply by referring to 10%～15% of the vertical force in the current rail transit code, and should be greater than this value;(3)When centrifugal force and traction braking force are superimposed, the traction braking force should not be reduced;(4)As the impact coefficient and lateral swing force are less studied in China, qualitative analysis of various factors that may lead to parameter changes of rack railway should be conducted based on the similarities and differences between rack-rail and wheel-rail.