跨径的增加对缆索承重桥梁颤振分析方法的影响  

Impacts of Increase in Span Length on Flutter Analysis Method of Cable-Supported Bridges

作　　者：杨德灿[1] 宛劲松[2] 

机构地区：[1]同济大学桥梁工程系 [2]湖北省交通规划设计院,湖北武汉430051

出　　处：《桥梁建设》2004年第5期23-26,共4页Bridge Construction

摘　　要：针对斜拉桥跨径突破1000m,悬索桥跨径达到2000～3000m,缆索承重桥梁的颤振特性发生的变化,着重讨论了斜拉索或吊索自身振动对颤振特性的影响以及现有分析方法的不适用性,提出了相应的分析方法调整对策。认为跨径突破后,斜拉索或吊索自身振动的影响必须考虑,而且求解特征方程时,必须使用全模态的方法才能计入索自身振动的影响;采用多链杆单元模型或构造新的广义自由度单元模型可以反映索自身的振型;使用全模态方法求解特征方程时,计算方法需要作适当的处理,才能使搜索到的特征值包含颤振模态。With reference to the changes of flutter behavior of cable-supported bridges due to increase in span length of a cable-stayed bridge over 1 000 m, and a suspension bridge up to 2 000～3 000 m, this paper investigates the impacts of natural vibration of the stay cables or suspension cables on the flutter behavior and the inapplicability of existing analysis methods, and proposes modifications to the corresponding analysis methods. It is considered in the investigation that the natural vibration of both the cables should be taken into account, and moreover, when characteristic equations are solved, the full-mode method must be employed in order to include the impacts of the natural vibration of the cables; the models of multi-link elements or the generalized DOF element can reveal the natural vibration modes of the cables perfectly; and appropriate treatments must be introduced into the solving process of the characteristic equations used with full-mode method in order to make the obtained characteristic solution include the flutter modes.

关 键 词：长跨桥 斜拉桥 悬索桥 缆索 颤振 振动分析 

分 类 号：U441.3[建筑科学—桥梁与隧道工程]