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Aeroelastic modeling to investigate the wind-induced response of a multi-span transmission lines system

  • Azzi, Ziad (DDA Claims Management) ;
  • Elawady, Amal (Department of Civil and Environmental Engineering, Florida International University) ;
  • Irwin, Peter (Extreme Events Institute of International Hurricane Research Center, Florida International University) ;
  • Chowdhury, Arindam Gan (Department of Civil and Environmental Engineering, Florida International University) ;
  • Shdid, Caesar Abi (Department of Civil Engineering, Lebanese American University)
  • 투고 : 2021.11.23
  • 심사 : 2021.12.15
  • 발행 : 2022.02.25

초록

Transmission lines systems are important components of the electrical power infrastructure. However, these systems are vulnerable to damage from high wind events such as hurricanes. This study presents the results from a 1:50 scale aeroelastic model of a multi-span transmission lines system subjected to simulated hurricane winds. The transmission lines system considered in this study consists of three lattice towers, four spans of conductors and two end-frames. The aeroelastic tests were conducted at the NSF NHERI Wall of Wind Experimental Facility (WOW EF) at the Florida International University (FIU). A horizontal distortion scaling technique was used in order to fit the entire model on the WOW turntable. The system was tested at various wind speeds ranging from 35 m/s to 78 m/s (equivalent full-scale speeds) for varying wind directions. A system identification (SID) technique was used to evaluate experimental-based along-wind aerodynamic damping coefficients and compare with their theoretical counterparts. Comparisons were done for two aeroelastic models: (i) a self-supported lattice tower, and (ii) a multi-span transmission lines system. A buffeting analysis was conducted to estimate the response of the conductors and compare it to measured experimental values. The responses of the single lattice tower and the multi-span transmission lines system were compared. The coupling effects seem to drastically change the aerodynamic damping of the system, compared to the single lattice tower case. The estimation of the drag forces on the conductors are in good agreement with their experimental counterparts. The incorporation of the change in turbulence intensity along the height of the towers appears to better estimate the response of the transmission tower, in comparison with previous methods which assumed constant turbulence intensity. Dynamic amplification factors and gust effect factors were computed, and comparisons were made with code specific values. The resonance contribution is shown to reach a maximum of 18% and 30% of the peak response of the stand-alone tower and entire system, respectively.

키워드

과제정보

The authors greatly acknowledge the help offered by Mr. Walter Conklin and Mr. Roy Liu-Marques in conducting the experiments at the NSF NHERI WOW EF (NSF Award No. 1520853). This research is supported by an NSF award (NSF Award No. 1635569). Funding from the Florida International University Graduate School (FIU UGS) Dissertation Year Fellowship (DYF) is greatly appreciated. The opinions, findings and conclusions expressed in this publication are those of the authors and not necessarily those of the funding agencies.

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