【作者】 吴振；

【导师】 梅葵花；

【作者基本信息】 长安大学 ， 桥梁与隧道工程， 2011， 硕士

【摘要】 随着桥梁技术的日益发展,大跨、超大跨桥梁的建设成为了当今桥梁发展的一个趋势。斜拉桥由于其跨越能力大的优点,越来越来越受到当今桥梁设计者的重视,尤其是新材料在超大跨斜拉桥桥中的应用研究,在国外已经成为一个研究热点。超大跨度斜拉桥结构柔性大,其几何非线性效应更为显著,成桥状态的静、动力特性变得更为复杂,因此,开展有关这一领域的研究十分重要。本文首先系统地叙述了斜拉桥计算的有限位移理论,总结了影响斜拉桥几何非线性的三个因素：垂度效应、轴力与弯矩耦合产生的梁-柱效应以及大位移效应。论述了斜拉桥合理成桥状态的评定原则,简述了斜拉桥索力优化的三类方法。其次,针对大跨径斜拉桥的结构特点,从主梁、主塔、斜拉索和边界条件等方面论述了斜拉桥有限元分析的建模方法：通过midas软件采用有限元法对主跨800m、1500mCFRP拉索和钢拉索斜拉桥进行了静力性能(包括恒荷载、车辆荷载、温度荷载)分析。再次,论述了大跨径斜拉桥三维有限元分析法的基本原理；然后对比分析了主跨800m、1500m CFRP拉索和钢拉索斜拉桥的动自振特性。最后,在综合考虑索一桥塔一桥面耦合的基础上,建立了索一桥塔一桥面耦合参数振动的非线性模型,并采用数值方法分析了初始扰动及阻尼等对拉索参数振动特性的影响。更多还原

【Abstract】 With the development of bridge technology, the constructions of great and massive bridges become the trend of the time. As an obvious advantage, super span ability of cable-strayed bridge has been attracting more and more designer. The application of some new material in massive cable-strayed bridge becomes a hot topic among researchers abroad. The structure of massive strayed bridges is soft as well as geometric nonlinearity, which made the bridges stativity and dynamicity more complex. Therefore, researching in this field is very important.Firstly, The thesis systematically describes the calculation of the finite displacement theory of cable-stayed bridge. Introducing its geometric nonlinearity influence by three factors:sag effect、axial force and bending moment produced by the coupling beam-column effect and displacement effect. Discussing the assessment principles of the stayed cable bridge. Breifly illustrate three categories of how to optimize the effort of cable-strayed bridges.Secondly, aiming at the structure characteristics of the cable-strayed bridges, the thesis illustrates the modeling method of finite element method in different aspects, like main girder、main tower, cable, boundary condition and so on. The static performance (including the constant load, vehicle load, temperature load) of the 800m-span and 1500m-span cable-stayed bridge with CFRP cables and another one with steel cables are analyzed contrastively through the midas software.Thirdly, the thesis discussing the basic theory of 3D finite elements in super cable-strayed bridges. The dynamic characteristics of the 800m-span and 1500m-span cable-stayed bridge with CFRP cables and another one with steel cables are analyzed contrastively。Finally,Considering with the sag, clination and geometry nonlinearity, a coupling parametric vibration model was built. By using this model, numerical results of CFRP cables and steel cables with the same condition are obtained, and the results demonstrate that the vibration is related with the ratio of initial disturbance and damping ratio。更多还原