Reliable computational models of transmission towers are key to improved hurricane risk management of transmission systems. However, a comprehensive understanding of involved complexities and their effects on the extreme wind performance of towers is not available. Particularly, buckling effects have not been captured properly and the failure of joints and the post-buckling behaviour of towers have not been investigated. Moreover, contributions of these and other complexities to key tower responses in the presence of uncertainties are not known. This paper presents an approach to modelling lattice towers that captures buckling and post-buckling, and joint slippage and failure and analyses their effects, while considering uncertainties, through a set of probabilistic, nonlinear pushover analyses in OpenSEES. Results for a double circuit vertical lattice tower indicate that buckling can lead to 30% reduction in the load-bearing capacity of towers. Joint slippage reduces the load-bearing capacity of the tower by 6%. It also considerably increases tower displacement. Connection failure can also occur in rare cases and it subsequently, changes tower’s failure mode. The proposed modelling approach can be used in risk analysis of transmission systems to investigate various performance levels and improve the design of towers.

输电塔的可靠计算模型是改善输电系统飓风风险管理的关键。但是，尚无法全面了解所涉及的复杂性及其对塔架极端抗风性能的影响。特别是，屈曲效果没有得到正确的捕捉，并且节理的失效和塔的后屈曲行为也没有得到研究。此外，在存在不确定性的情况下，这些复杂性和其他复杂性对关键塔式反应的贡献尚不明确。本文提出了一种建模桁架塔的方法，该方法可捕获屈曲和后屈曲，以及联合滑移和破坏，并通过OpenSEES中的一组概率性非线性推覆分析在考虑不确定性的同时分析其影响。双回路垂直格构塔的结果表明，屈曲可导致塔的承载能力降低30％。联合滑移使塔架的承载能力降低了6％。这也大大增加了塔架的位移。连接故障也可能在极少数情况下发生，并随后更改塔的故障模式。所提出的建模方法可用于输电系统的风险分析，以研究各种性能水平并改善铁塔的设计。