钢管混凝土拱桥的稳定性分析-桥梁与隧道工程专业论文.docxVIP

钢管混凝土拱桥的稳定性分析 钢管混凝土拱桥的稳定性分析 摘 要 拱桥是桥梁的基本桥型之一，因其造型优美，所以在工程中被广泛应用。 钢管混凝土拱桥解决了拱桥高强度材料应用和施工两大难题，所以在我国得到 了迅速发展，随着跨径的增大，稳定性问题变得越来越突出，这已成为拱桥设 计的重要控制因素之一。 稳定问题通常分为两类，第一类稳定问题可以归结为求特征值问题，计算 简单。第二类稳定问题，因为考虑了几何非线性、材料非线性和初始缺陷的影 响，所以计算出的极限承载力更符合工程实际。 本文通过有限元分析软件MIDAS／Civil 2006对一钢管混凝土拱桥的线弹性 稳定性影响因素进行了分析，探讨了拱桥矢跨比、横撑的形式和刚度、拱肋刚 度和吊杆的刚度对稳定性的贡献，提出了一些对拱桥设计具有参考价值的建议。 用Ansys大型有限元分析软件对一钢管混凝土拱桥进行了特征值屈曲分析 和非线性屈曲分析，非线性分析的过程中，引入了钢管混凝土构件的本构关系 模型，以考虑材料非线性对稳定性的影响，分析的结果表明：线性特征值屈曲 分析的安全系数明显偏大，可能产生非保守的结果；几何非线性对钢管混凝土 拱桥的稳定性影响很小；考虑双重非线性因素计算出的临界荷载值要远小于线 弹性分析和几何非线性分析的结果，得出钢管混凝土拱桥稳定性分析需要同时 考虑几何非线性和材料非线性的结论。 关键词：钢管混凝土拱桥稳定性屈曲非线性 Stability Stability Analysis of Concrete Filled Steel Tubular Arch Bridge ABSTRACT Arch bridge，with extremely lligh aesthetic value，aetmg as one of the fundamental bridge tyl∞s，is widely applied in engineering．CFST(Concrete Filled Steel Tube)arch bridge has solved the problem of the application of higll-strength material of arch bridge and the problem of the construction of arch bridge,two main puzzles of bridge．Therefore，it has gained a booming opportunity in our country．With the increase of the span of the arch bridge,the stability problem becomes more and more evidence and it is one of the most important control factors of arch bridge design． Stability problem is divided into two sorts．The first one can come down to evaluate eigenvalue problem finally,which is easy to be calcadated．Duing to the effect of the geometry noIllinear，the material nonlinear and original bug，the ultimate load calcadeated by the second one is more reasonable comparing to the true resnlt． Tllis paper studys on influencing factors of stability of arch bridge by MIDAS／Civil 2006，search the contribution which has been given by Rise-span ratio，the form and stiffness of transverse bracing，the stiffness of Arch Rib and Hanger Rod，and give some advices on designing arch bridge． Analyse the stability ofthe CFST arch bridge by eigenvalue buckling analysis method and nonlinear stability buckling analysis method