国家体育场多目标等效静风荷载

针对大跨结构的风振响应特点，研究多目标等效静风荷载的分析方法，并采用该方法对国家体育场等效静风荷载进行了研究。该等效静风荷载分析方法的基本过程是：根据结构风振响应特性，选择风荷载的主要本征模态和结构主导振型惯性力作为构造多目标等效静风荷载的基本向量，根据最小二乘法，得到基本向量的最优组合系数，从而得到针对多个等效目标的等效静风荷载。国家体育场的分析结果表明：在所有风向下的风振响应中，背景响应远大于共振响应，其中0°风向和270°风向对结构最为不利；在针对多等效目标的等效静风荷栽作用下，所有关键位置的节点位移响应和支座反力都与实际动力响应极值吻合较好。

Equivalent Static Wind Load for Multiple Targets of China's National Stadium

According to characteristics of large-span structures, a methodology was proposed to analyse the equivalent static wind load for multiple targets of China's National Stadium. The general principles were, taking dominating eigen-modes and dominating vibration modes as basic vectors to express equivalent static wind load for multiple targets; and then obtaining optimization coefficient with least square approximation method; thus, obtaining the equivalent static wind load for multiple targets. Upon the case study, it was found that background response was much more than resonant response for all of the wind directions with most unfavorable at 0 degree and 270 degree directions. And structural response of all nodes and all supports under a single equivalent static wind distribution were in good agreement with peak values under actual dynamic wind loads at the same time.