+Advanced Search

Fragility Analysis on Vertical Earthquake of UHV Long Cantilever Transmission Tower Cross-arm Structure
Author:
  • Article
  • | |
  • Metrics
  • |
  • Reference
  • |
  • Related
  • |
  • Cited by
  • |
    Abstract:

    The ±800 kV ultra high voltage (UHV) long cantilever transmission tower cross-arm structure belongs to a high-level horizontal long cantilever structure sensitive to the vertical seismic effect. It is urgent to conduct vertical seismic fragility analysis research on cross-arm structures. To address this, a framework for vertical seismic fragility analysis, considering multiple performance levels, was proposed for the UHV long cantilever transmission tower cross-arm structure. Firstly, a finite element model was established with the UHV long cantilever transmission tower as the research object, and the vertical dynamic characteristics of the structure were analyzed. Secondly, based on the stress ratio of the main component at the end of the cross-arm structure, multiple performance levels for slight, moderate, and severe damage to the cross-arm structure were established. Finally, a vertical seismic fragility analysis based on a probabilistic seismic demand model was carried out for the cross-arm structure. The analysis results show that the long cantilever transmission tower is significantly affected by higher-order vibration modes under vertical earthquake, and the first three vertical modes that contribute significantly to the vertical response of the structure are the 16th, 26th, and 29th modes, respectively. Under vertical seismic action, the end main component is the main load-bearing member of the cross-arm structure. Compared with considering the strength failure of the main component in tension bending at the end of the cross-arm structure, the failure probability of the cross-arm structure considering the instability failure of the main material in compression bending is significantly higher under the given vertical seismic intensity.

    Reference
    Related
    Cited by
Article Metrics
  • PDF:
  • HTML:
  • Abstract:
  • Cited by:
Get Citation
History
  • Online: January 22,2025