国内外规范输电线路铁塔风荷载特性对比

Contrast Study of Wind Load Characteristics for Transmission Towers Based Foreign Standards

输电铁塔属于风敏感结构,风与结构的相互作用十分复杂,风荷载是设计的主要控制荷载。随着涉外工程的增多,准确把握国外规范的风荷载取值成为铁塔设计的关键一步。首先对国际上通用的输电线路设计规范(包括ASCE 74-2009、IEC 60826及BS EN 50341)中关于铁塔风荷载的计算原理进行梳理和分析,得到了一套完整的铁塔风荷载计算方法。以某一典型的输电铁塔为研究对象,分别按照国外规范计算得到了塔身和横担的风荷载,分析了结构各层的风荷载分布特点,并与我国规范的计算结果进行对比研究。通过研究,揭示了国外规范计算铁塔风荷载的特点,结果可作为输电铁塔抗风设计的参考。

With the complex interaction between wind and structure, transmission towers belong to wind-sensitive structures and the wind load becomes the main problem in structure design. With the increase of transmission line projects undertaken abroad, to accurately understand the wind load specifications in foreign standards is a fundamental and key step for designing transmission towers. In this paper, an analysis is conducted on the calculation principles of wind load for towers in different international transmission line codes （including ASCE74-2009, IEC60826 and BS EN50341）, and a calculation method for tower wind load was obtained. Based on a typical transmission tower, the wind loads of the tower body and cross-arm were calculated respectively in accordance with foreign standards. Meanwhile, the wind load distribution characteristies of structural layers were analyzed and compared with those calculated with Chinese standards. The wind load characteristics of transmission towers in foreign standards obtained in this study may be referred in the design of wind loads for transmission towers in foreign countries.