Wind and Structures

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Longitudinal reaction on conductors due to tornado wind load

  • Dingyu Yao (Department of Civil and Environmental Engineering, Western University) ;
  • Ashraf El Damatty (Department of Civil and Environmental Engineering, Western University)
  • Received : 2024.01.23
  • Accepted : 2024.03.04
  • Published : 2024.04.25
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Abstract

The longitudinal force resulting from tornado loads on transmission line is considered a crucial factor contributing to the failure of transmission line structures during tornado events. Accurate estimation of this longitudinal force poses a challenge for structural designers. Therefore, the objective of this paper is to provide a set of charts that can be easily used to estimate the peak longitudinal forces transferred from the conductors to a tower. The critical wind field and corresponding configuration considered in this paper are previously studied and determined. The charts should account for all the conductor parameters that can affect the value of the longitudinal force. In order to achieve that, a parametric study is first conducted to assess the variation of the longitudinal forces with different conductor parameters, based on the critical tornado configuration. Results of this parametric study are used to develop the charts that can be used to calculate longitudinal forces by adopting a multi-variable line regression. The forces calculated from charts are validated by finite element analysis. An example for the usage of the charts is provided at the end of this paper.

Keywords

Acknowledgement

The authors would like to acknowledge Hydro One Ontario Company Canada and the Natural Sciences and Engineering Research Council of Canada (NSERC) for their in-kind support, their collaboration in this project, and for the financial support provided for this research.

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