高层建筑简化振型及在结构风振计算中的应用

Simplified Mode of High Rise Buildings and Its Application in Wind Induced Structural Vibration Analysis

摘要:

基于弯剪型悬臂梁模型分析高层建筑的动力特性，给出控制高层建筑振型形状的特征参数；通过对具有不同特征参数的基阶振型曲线进行拟合分析，得到既形式简洁又能准确反映实际结构基阶振型的简化模型；同时，给出控制简化振型形状的振型指数的确定方案.将简化振型应用于实际高层建筑的结构风振计算，结果表明，采用该简化振型能更准确地体现风荷载沿建筑高度的分布情况，提高风荷载和风振响应计算的精度.

关键词:高层建筑; 基阶简化振型; 结构特征参数; 风荷载; 结构风振计算

Abstract:

Dynamic characteristics of highrise buildings is analyzed in this paper with the help of shearflexural type cantilever beam model; and then, a structural characteristic parameter governing the mode of highrise buildings is given. Through the fitting analysis of fundamental mode shapes with different structural characteristic parameters, a simplified model of fundamental mode is obtained, which has a concise expression but can accurately reflect the prototype fundamental mode shapes of highrise buildings; at the same time, the method for determining the mode index which governs the shape of simplified modes is given. The simplified fundamental mode of this paper is applied in the windinduced vibration analysis of an actual highrise building; the result shows that, by using the simplified mode, the wind load distribution along the height of the building can be reflected more precisely and the computational accuracy of wind loads and windinduced responses of the building can be improved.

Key words:high-rise buildings; simplified fundamental modes; structural characteristic parameter; wind loads; wind induced structural vibration analysis