文档介绍：毕业论文
学生姓名: 张炼学号: 20082398
学院: 土木工程与力学学院
专业: 工程力学
论文题目: 受端部激励作用斜拉索的非线性动
动力特性分析与降幅控制方法研究
指导教师: 秦金旗讲师
评阅教师: 丁科副教授
2012 年 05月 23 日
摘要
斜拉索是斜拉桥的主要受力构件之一。因斜拉索具有高强度的力学特点而应用非常广泛,但是同时斜拉索具有质量轻、结构柔及阻尼低等特点,在风雨、车辆等荷载作用下,极易发生大幅度的振动。这种振动对斜拉桥成桥后和在建过程中的耐久性和安全性有很大的危害,有可能引起索的疲劳断裂,容易在索锚结合处产生疲劳裂纹,尤其是在施工过程中,合理的桥跨结构还没有完全形成,这种大幅度的振动对桥梁的安全性与耐久性产生很大的危害。因此,研究实际工程中受梁端激励斜拉索的振动具有非常重要的实际工程意义。
本文主要研究受端部激励作用斜拉索的非线性动动力特性分析与降幅控制方法研究。避免实际工程中产生共振,提高桥梁安全性与耐久性。本文第二章是对受端部激励作用的斜拉索的动力学分析。而用多尺度法近似求解既有平方非线性又有立方非线性的非线性动力学方程是合适的。所以运用多尺度摄动方法,对斜拉索可能发生的非线性振动进行理论研究,采取Runge-Kut ta数值分析方法获得受梁端激励拉索的非线性振动响应和幅频特性曲线,研究工程结构中斜拉索的非线性振动特征。第三章通过具体算例得到阻尼控制下斜拉索的动力响应。通过第三章得到的结论,在第四章对受梁端激励作用斜拉索进行主动控制,从而找到避免产生共振的方法。
关键词:斜拉索;非线性;振动响应;幅频特性;共振
Title:At the end of the incentive effect by nonlinear dynamic characteristics of stay-cables analysis and research by control method
Abstract
Stayed cables of cable-stayed bridge is one of the main ponents. Because of stay-cables with high-strength mechanics characteristics and application is very wide, but at the same time stay-cables has light quality, soft and damping characteristics such as structure, in the wind and rain, vehicles and so on load, easily happened the vibration of the greatly. This vibration on cable-stayed bridge under construction bridge and in the process of durability and safety have great harm, may cause the fatigue fracture of the cable, easy to cable in department of fatigue crack, especially in the construction process, the reasonable span structures of the bridge is not fully formed, the large vibration the safety of the bridge and the durability produce great harm. Therefore, the study in practical engineering the girder ends by the vibration of stay-cables incentive has very important practical engineering significance.
This paper mainly studies at the end of the incentive effect by stay-cables dynamic characteristics of nonlinear dynamic analysis and research by control method. Avoid resonate in practical engineering, improve safety and durabi