以风洞试验相似理论和随机振动理论为基础,提出了风振分析中的脉动风荷载频率补偿问题,即根据已有的测点风压数据重构脉动风荷载的高频部分,其目的是解决由于缩尺比导致的试验采样频率转化为原型荷载频率后所存在的高频截断问题。对脉动风荷载频率补偿的必要性进行了探讨,指出被截断的高频信号可能导致结构风振响应分析结果失真;结合脉动风荷载能谱理论和本征正交分解(POD)技术提出了一种实用的频率补偿方法;结合一风洞试验分析了考虑频率补偿与否对单层网壳结构风振响应分析结果的影响,验证了方法的有效性。
Based on similarity theory in wind tunnel test and random vibration theory,the frequency compensation of fluctuating wind loads in wind-induced response analysis is proposed.The frequency compensation refers to the method that reconstructs the high-frequency part of fluctuating wind loads based on experimental data.The purpose of this method is to solve the high-frequency cut-off problem owing to the scaled ratio in wind tunnel tests.Firstly the necessity of frequency compensation problem is discussed,then a practical method of frequency compensation is proposed by combining the fluctuating wind energy spectrum theory and the Proper Orthogonal Decomposition technique.According to this method,the wind-induced response of a single layer reticular shell is analyzed based on a wind tunnel test in order to investigate the influence of high-frequency part of fluctuating wind loads.The results indicate the validity of the method proposed.