Wind-induced responses of transmission towers:
A parametric study using time and frequency domain methods
Guohui Shen,Hangcong Yu,Yingneng Zhao,Liang Yu,Buhui Li
Abstract
The wind-induced responses of the transmission towers obtained using time and frequency domain methods were
investigated and compared. The influence of key parameters, including the cut-off frequency ωu, time step, sampling period, and
frequency amount N, on the simulating results was clarified in the process of the harmonic superposition method (HSM).
Furthermore, the effects of the wind spectrum and coherence function on the transmission towers' responses are examined.
Finally, the appropriate values for the cut-off frequencies for obtaining the displacement and acceleration responses were
provided. In the process of HSM, it is recommended to use a time step of 2π/2ωu. Otherwise, the high-frequency component of
the simulated spectrum will be distorted or inadequate if a larger or smaller time step is applied. The recommended sampling
length is 2πN/ωu. Using a great sampling length will result in a repeating time history. If the cut-off frequencies used in the
HSM of the time domain analysis and the upper limit of the integral in the frequency domain analysis are the same, the
displacements of the two approaches are almost equal. In terms of acceleration, the responses at the cut-off frequency prior to
and following the first-order circular frequency differ significantly. Suggestions for cut-off frequency selection are made based
on response type. For the displacement response, the cut-off frequency should be more than the first-order circular frequency,
while for the acceleration response, it should be at least 8π. The coherence function has a significant effect on the response, with
the frequency-independent coherence function yielding greater standard deviations for both displacement and acceleration than
the frequency-dependent model.
Key Words
cut-off frequency; frequency domain method; harmonic superposition method; time domain method; transmission
tower
Address
Guohui Shen — Institute of Structural Engineering, Zhejiang University, Hangzhou, China
Hangcong Yu — The Architectural Design and Research Institute of Zhejiang University Co., Ltd. Hangzhou, China
Yingneng Zhao — China Energy Engineering Group Zhejiang Power Design Institute Co. Ltd, Hangzhou, China
Liang Yu — China Energy Engineering Group Jiangsu Power Design Institute Co. Ltd, Nanjing, China
Buhui Li — China Energy Engineering Group Jiangsu Power Design Institute Co. Ltd, Nanjing, China
PDF Viewer
Preview is limited to the first 3 pages. Sign in to access the full PDF.
