输电塔钢管构件涡振疲劳临界起振风速的探讨  

Study on Critical Wind Speed Concerning Fatigue Behaviors of Circular Cylinders with Vortex-induced Vibration in Transmission Towers

作　　者：赵张峰 邓洪洲[1] 

机构地区：[1]同济大学建筑工程系,上海200092

出　　处：《特种结构》2015年第5期54-61,共8页Special Structures

基　　金：国家自然科学基金资助项目(No51578421)

摘　　要：输电塔钢管构件易出现涡激振动引发的疲劳破坏。本文给出临界起振风速的确定方法,以避免疲劳破坏的发生。本文针对钢管构件两端铰支和两端固支这两种典型的支承条件,结合结构动力学理论,推导两种支承条件下钢管构件发生涡振时构件中部的最大振幅公式,并根据风洞试验数据进行验证,进而推导出构件最大弯矩公式。基于平均风速分布符合Weibull分布的假定,结合疲劳理论得出构件的容许应力幅公式。最后结合算例,得出构件的容许应力幅,并根据构件的最大弯矩公式结合焊缝分布形式计算法兰连接以及十字插板连接构件的焊缝应力幅,通过比较容许应力幅以及焊缝应力幅,给出疲劳寿命为50年的临界起振风速。Fatigue failure occurs easily to circular cylinders of transmission towers because of vortex-induced vibration. This article presents a method to predict critical wind speed to avoid fatigue failure. Based on the theory of structural dynamics and the two typical joints conditions of circular cylinders （both ends of ideal hinged connection and both ends of rigid connection）, equations to calculate maximal amplitude in the middle of circular cylinders have been worked out. These equations have been further been verified with data in wind tunnel tests and help deduce equations for maximal moment of flexure. At the same time, on the assumption of the consistency of actual wind distribution and Weibull distribution and with the aid of fatigue theory, allowable stress amplitude equations have been obtained. Finally, by comparison of allowable stress amplitude, resulted from integration of allowable stress amplitude equations and the real case, and stress amplitude of weld of connection, given by combination of maximal moment equations and weld of connection of flange and cross-gusset from the real case, a qualitative result of critical wind speed to permit fatigue with life of 50 years is provided.

关 键 词：钢管构件 容许应力幅 焊缝应力幅 法兰和十字插板连接 临界起振风速 

分 类 号：TM753[电气工程—电力系统及自动化] TU392.3[建筑科学—结构工程]