中文摘要：

为分析大跨桥梁在脉动风作用下的抖振响应,针对传统桥梁抖振计算采用的广义振型为三维空间状态,分析过程复杂等问题,提出基于独立振型的抖振分析思路,以经典结构动力学理论和风洞试验为基础,根据能量守恒原理,将以广义振型表示的抖振响应分析过程表达为易于采用矩阵表示的n个独立振型的形式,使得结构动力计算由三维空间状态转化为一维状态,简化了分析过程,并且很容易获得关心自由度上的抖振响应,在此基础上,采用该方法对1座主跨800m的三跨悬索桥进行了抖振响应分析。研究结果表明：由于大跨度桥梁主梁刚度较小,其在脉动风作用下的抖振位移响应数值较大,结构设计中不能忽略。

英文摘要：

In order to analyze buffeting response of long-span bridge subject to gust wind,and solve the problem of complexity of traditional buffeting analysis method in which the generalized mode-shape is corresponding to one special state of the structure in space,a method based on mode shapes of orthogonal DOF（degree of freedom）was proposed in this paper.Based on dynamics of structure and wind tunnel experiment,this paper derived bridge’s buffeting response in form of mode-shapes of orthogonal DOF.Every mode-shape of orthogonal DOF could be expressed by one DOF of structure.According to the principle of conservation of energy,the generalized mode-shapes were instead by mode shapes of orthogonal DOF which simplified the buffeting analysis,and the concern dynamic responses could be obtained easily.Finally,the above method was used to calculate buffeting responses of a three span suspension bridge with main span of 800 m.The results show that the buffeting responses of long-span bridges are large and cannot be ignored in design.1tab,3figs,20 refs.