格构桥面系在铁路拱桥上的应用

Application of Lattice Beam Decking on the Railway Arch Bridge

山区铁路横跨深窄峡谷多采用拱桥,由于刚度控制要求,铁路拱桥一般优先采用动力性能良好的整体性桥面,如连续箱梁等。但山区建设条件复杂,大型机具设备进场条件欠缺,整体性桥面施工较为困难,有必要研究既满足动力性能又便于架设的新桥面形式。本文以宜万铁路124 m非对称坡拱野三河大桥为研究对象,以车桥耦合分析为理论基础,对桥面分别采用格构方案和连续箱梁方案建立空间有限元模型,进行车桥动力仿真分析,对复杂山区条件下铁路钢管混凝土拱桥的桥面系方案进行比选。通过对结构自振频率、列车运行安全性与舒适性进行评估,论述首次应用在铁路拱桥上的格构桥面系方案是可行的,本文研究成果可为类似工程桥面系设计提供参考。

Arch bridge is often used in the mountains railway across the deep narrow canyon.Due to the control requirement of the stiffness,the railway arch bridge generally prefers to adopt integrity-decking that has a good dynamic performance,such as the continuous box girder.However,considering complex construction conditions,lacking of large-scale machinery and equipment entering conditions and difficult integrity-decking construction in the mountains,it is necessary to study a new form of bridge decking that satisfy the dynamic performance and is easy to construct.The paper focuses on the Yesanhe Bridge of Yiwan Railway whose main arch span is 124 m and the first asymmetric slope arch in china,based on the theory of vehicle-bridge coupling analysis,establishes the space finite element models for Yesanhe Bridge about the lattice program and continuous box program to make a series of Vehicle-Bridge Dynamic Simulation Analysis,and discuss the railway bridge decking program choices of the concrete-filled steel tube arch bridge in the complex mountainous condition.Through evaluation of the natural frequency of the structure,running safety and comfort assessment,this paper is the first to illustrate the feasibility of Railway Arch Bridge decking program about the lattice beam.This study can provide a reference for bridge decking design of other similar projects.