【作者】 王伟；

【导师】 郑凯锋；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2004， 硕士

【摘要】 本文首先总结铁路钢桁梁桥传统计算方法，然后提出按照全桥结构仿真分析的技术思想建立完整、统一的钢桁梁结构分析体系，并在该体系下构造全桥所有承载构件的组合有限元模型，由此克服传统简化计算由于铰接或刚接假设、边界条件假设和忽略桁架杆件横向尺寸效应假设等带来的不足。针对铁路上广泛使用的64m下承式简支钢桁梁桥，使用板壳元、实体元等单元建立精细的全桥组合有限元分析模型，并在此基础上进行大规模的全桥结构效应分析计算。主要计算恒载、列车荷载、橫向风荷载、纵向制动荷载及其相关组合作用下主桁杆件、桥面系、联结系杆件的变形及各组成板件的应力分布，以及横向联结系的横向框架在竖向荷载及横向荷载作用下的变形情况和主桁大节点局部应力分布。最后，论文还将模型计算结果与简化方法计算结果进行对比分析。论文的详细计算和对比分析有助于更好地了解钢桁梁桥的详细受力性能。更多还原

【Abstract】 Firstly, this paper contains a brief introduction of traditional calculation methods of railway steel truss bridge, then model all structural components of this type bridge in detail under a unified system which is based on entire bridge simulation. This entire bridge model can get results with sufficient accuracy, thoroughness and reliability, which can overcome some shortcomings in traditional simplified methods based on pin-jointed truss members and beam elements, such as inaccurate description of connection among the members of truss and between the members and deck system, and inaccurate hypothesis boundary conditions, and overlooking effects on cross width of members of truss. Based on a case study for a simple-supported through steel truss bridge with main span of 64m, which is widely used in railway engineering, a entire bridge model, which includes a combined use of shell elements and brick elements, is presented. Under the actions of dead loads, live loads, lateral wind load, longitudinal brake load and coherent combination of these factors, the detailed distribution of stress and deformation of members and joint plates in main truss, deck system and link system are analyzed. At the same time, the detailed deformation and stress distribution of bracing frame under vertical and lateral loads and even local stress distribution of joint plates are also presented in this paper. Finally, the results of entire bridge model based on integrated element method are compared with those of traditional simplified methods. All calculation results and comparison are useful to know structural characters of steel truss bridge in detail.更多还原