既有高耸钢结构风致疲劳寿命时域分析方法及实例

以某港区高杆照明装置为例,探讨了既有高耸钢结构风致疲劳寿命的时域分析方法。该方法首先通过现场实测校正结构动力分析模型,而后采用谐波叠加法模拟脉动风场,计算脉动风动力作用下结构控制细节应力谱,最后基于现场风向风速监测资料统计得到的各风向概率及相应的风速分布,采用热点应力法估算各控制细节年疲劳损伤度及剩余疲劳耐久年数。实例计算结果与现场实际情况吻合较好,可供类似结构的风致疲劳分析参考。

TIME-DOMAIN ANALYZING METHOD AND CASE OF WIND-INDUCED FATIGUE FOR EXISTING HIGH-RISE STEEL STRUCTURE

Taking the fatigue life analysis of a high mast lighting system for example , it was discussed the time-domain analyzing method of wind-induced fatigue for existing high-rise steel structure.Firstly , the calibration model was got by the field measurement of structure dynamic characteristic.Secondly , wave superposition method was used to simulate stochastic wind field and calculate the stress spectrum of structure under fluctuating wind load action.Thirdly , probability of wind direction and corresponding distribution of wind velocity were obtained based on statistics of in-situ measurement data of wind speed and direction.At last , the fatigue damage and predict residual life could be calculated based on hot-spot stress method and linear damage rule.