铁路桥梁上线路设置短夹直线反向曲线的研究解决思路

Study on How to Arrange the Reverse Curves with Short Intermediate Straight Line on Railway Bridge

针对《铁路桥涵设计基本规范》(TB10002.1—2005)中规定"桥上应避免采用反向曲线"与《铁路线路设计规范》(GB50090.1—2006)中"明桥面桥不应设在反向曲线上"不一致的情况,通过分析总结多条线在铁路桥梁上线路设置短夹直线反向曲线存在的具体问题与解决办法,提出其他铁路项目在具体设计中处理此类问题可借鉴的解决思路:铁路设计一般情况下应遵循"桥上应避免采用反向曲线"的选线理念;困难条件下,应采取较好的线路条件,反向曲线的夹直线长度最少应满足1列运营列车长度;特殊困难条件下,桥梁上反向曲线夹直线长度不满足1列运营列车长度时,应通过线路平纵断面优化、桥改路等多方案经济技术比较辅以相关研究(如仿真检算)进行充分研究论证,以确定最终方案。

There is conflict between the two design codes, Basic Code for Design of Railway Bridge and Culvert （ TB10002. 1-2005 ） , Code for Design of Railway Route （ GB50090. 1-2006 ） , because the former stipulates that “all the bridges shall not be located in the area with reverse curves” and the latter only stipulates that“the open-deck bridge shall not be located in the area with reverse curves”. To solve that conflict, after analysis and summarization on lots of specific situations and solution measures in railway engineering practices about arranging reverse curves with intermediate straight line on railway bridges, this study put forward valuable solution schemes on how to solve the problems in the designs for similar railway projects in future. The conclusions drawn from this study are as follows：（ a） In general, railway design shall be in accordance with the principle of“all the bridges shall not be located in the area with reverse curves”. （ b） In difficult situation, good railway route condition should be ensured, and the length of the intermediate straight line between the reverse curves should at least meet the length requirement of one operating train. （ c） In specially difficult condition when the length of intermediate straight line between reverse curves cannot meet the length requirement of one operating train, the final scheme should be determined based on technical economy comparison among multiple schemes, such as route plane and profile optimization, replacing bridge with subgrade and so on, accompanied by relevant researches （ e. g. simulation calculation） and argumentations.