重载铁路单线32 m钢-混组合梁静动力性能研究

Research on Static and Dynamic Performance of Heavy-Haul Railway Single Track 32m Steel Concrete Composite Beams

为促进“自重轻、施工快速便捷、经济性良好”的中小跨径钢-混组合梁在重载铁路领域的合理使用,针对单线32 m钢-混组合梁,采用通用有限元的方法开展静力性能研究,采用刚柔耦合的多体动力学方法进行车-轨-桥耦合动力性能研究。静动力性能分析显示,(1)单线重载铁路(30 t轴重)32 m钢-混组合梁可采用工字钢主梁高2.6 m、桥面板厚20 cm(横向支点40 cm)双工字钢组合截面型式;(2)双工字钢钢-混组合梁抗扭刚度较弱,在计算横向变形时应考虑截面畸变变形影响;(3)横隔梁布置间距宜根据施工阶段结构稳定性确定,不宜过小;(4)在列车速度<80 km/h、轴重<40 t时,车桥动力响应均在规范允许范围内。综合研究表明,在重载铁路领域使用中小跨径的钢-混组合梁具有可行性,研究结果可供类似工程参考。

To promote the rational use of small and medium-sized steel-concrete composite beams(which are light self-weight,fast and convenient construction,and good economy)in the field of heavy-haul railways,this article focused on the static performance of a 32 m steel-concrete composite beam on a single track heavyhaul railway by using a universal finite element method.The dynamic performance of the vehicle rail bridge coupling was studied using a rigid-flexible coupling multi body dynamics method.The research results indicate that:(1)The 32 m steel-concrete composite beam of a single track heavy-haul railway(30t axle load)can adopt a 2.6 m I-shaped steel beam,with a bridge deck thickness of 20 cm(horizontal support point of 40 cm)and a double I-shaped steel composite cross-section.(2)The torsional stiffness of the double I-beam steelconcrete composite beam is relatively weak,and the influence of section distortion deformation should be considered when calculating lateral deformation.(3)The spacing between the transverse beams should be determined based on the structural stability during the construction phase,and should not be too dense.(4)When the train speed is less than 80 km/h and the axle load is less than 40 t,the dynamic response of train and bridge are all within the allowable range of the specifications.Comprehensive research has shown that the use of small and medium-sized steel-concrete composite beams in the field of heavy-haul railways is feasible,and the research results can provide reference for similar projects.