Critical Parameters and Configurations Affecting the Analysis and Design of Guyed Transmission Towers under Downburst Loading
Publication: Practice Periodical on Structural Design and Construction
Volume 22, Issue 1
Abstract
In past years, many electrical transmission lines have failed during downbursts. This study is part of a research program aimed at understanding the behavior of transmission lines under localized winds. Most downbursts need to be modeled using computational fluid dynamic (CFD) models; this is not an easy task for engineers in general. This paper focuses on replacing the complicated velocities obtained from CFD models with simplified loads that represent, in a more practical fashion, the critical downburst configurations causing the guyed transmission towers to fail. Different options are considered in terms of the location and nature of the design velocity associated with different configurations. The profile of the horizontal velocity is developed. A practical simplified load corresponding to each of the critical configurations is developed. Detailed steps of the conductors’ reaction calculations are provided. A simplified procedure is developed for designing downburst-loaded guyed transmission towers.
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Published In
Practice Periodical on Structural Design and Construction
Volume 22 • Issue 1 • February 2017
Copyright
© 2016 American Society of Civil Engineers.
History
Received: Jan 22, 2016
Accepted: Jul 20, 2016
Published online: Aug 30, 2016
Discussion open until: Jan 30, 2017
Published in print: Feb 1, 2017
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