【作者】 巩鹏飞；

【导师】 郑史雄；

【作者基本信息】 西南交通大学 ， 桥梁与隧道工程， 2012， 硕士

【摘要】 随着科学技术的发展,在现代桥梁工程中,正在逐渐向着大跨度、主梁更柔的方向发展,但因此桥梁的风致振动也成为一个不可忽视的问题。桥梁的风致振动不仅会对桥梁的关键截面应力和结构的疲劳性能有显著的影响,而且对桥梁的行驶舒适度及桥梁施工的安全性均会产生不利影响。在风致振动中抖振是一种很重要的限幅振动,对其分析的方法有两种：时域法和频域法：时域法在现在的抖振分析中占有不可忽略的作用。本文以某公铁两用钢桁斜拉桥为背景,对其成桥态和施工态进行了抖振线性时域分析。具体所作工作如下：1.根据斜拉桥主梁的结构特点及桥塔特点,分别对其进行了三维脉动风场模拟。2.利用Scanlan提出的准定长气动力公式计算出斜拉桥各个界面的抖振力,并编译了一套了在ANSYS中加载简便方法。3.运用ANSYS对某公铁两用钢桁斜拉桥进行简化建模,进行了模态分析和抖振分析。4.针对该桥的主梁和桥塔进行了线性抖振时域分析,计算了关键截面的内力和位移。5.根据本文的结果,总结了一些对实际工程有一定参考价值的结论。更多还原

【Abstract】 With the development of science and technology, the cable-stayed bridge is gradually developing into long span and deck more flexibility, but the wind-induced vibration of the bridge has also become an issue can not be ignored. The wind-induced vibration of bridge not only have significant impact on the stress of key section of the bridge and fatigue properties of the structure, but also have adverse effects on driving comfort at the using stage and safety at building stage. Buffeting is one of extremely important limit amplitude vibration, which has two method named frequency-domain simulation and time-domain simulation to analyze. Time-domain simulation plays a momentous role in buffeting analysis.In this thesis, taking one combined highway and railway steel truss cable-stayed bridge as the background, linear time-domain buffeting analysis at using and building stage is studied. The major work is shown as follows:1. According to the characteristics of the deck and tower, three-dimensional fluctuating is simulated.2. Buffeting force of key section of bridge calculated by using Scanlan’s quasi-steady aerodynamic theory. A set of code which is easy to load the buffeting force on model in ANSYS is compiled.3. The simplified model of combined highway and railway steel truss cable-stayed bridge is built in ANSYS, which used to make the modal analysis and buffeting analysis of the model.4. Making the linear buffeting time-domain simulation analysis for the deck and tower to calculate the internal force and displacement of the key sections of bridge.5. According to the result of this thesis, some conclusions that have certain reference value in engineering are summarized.更多还原