Abstract
The present study introduces a fully coupled time-domain analysis of a multi-span suspension bridge supported by two floating towers, considered for crossing the wide and deep fjords along the west coast of Norway. The time-domain analysis is performed with a finite element model considering simultaneously the turbulent wind, irregular inhomogeneous ocean waves and sheared ocean current. The numerical results suggest that under extreme conditions with a return period of 100 years, the bridge horizontal response is dominant and governed by the low-frequency modes. For the vertical and torsional responses, the largest contributions are due to the respective motion components of the low-frequency horizontal motion-dominated modes. The investigation into the significance of the aerodynamic and hydrodynamic load reveals that in the case studied, over 80% of the bridge girder response is due to the aerodynamic excitation. The hydrodynamic loads acting on the floating towers are small due to a relatively small significant wave height in the fjord and the counteracting aerodynamic damping effect. By considering the inhomogeneity of the waves, i.e. different conditions at the two floating supports, the contribution of the aerodynamic action to the lateral, vertical and torsional dynamic responses increases by 6%, 7% and 9% respectively.
| Original language | English |
|---|---|
| Pages (from-to) | 19-31 |
| Number of pages | 13 |
| Journal | Journal of Wind Engineering and Industrial Aerodynamics |
| Volume | 177 |
| DOIs | |
| Publication status | Published - Jun 2018 |
Bibliographical note
Funding Information:This study is conducted as part of the research project “Wind-induced vibrations of long-span bridges” supported by Norwegian Public Roads Administration . The assistance by NPRA in providing the information on the floating bridge concept and the reference reports is gratefully acknowledged. The work performed by the former master students, Sondre Aspøy and Sindre Stensbak, on a separate finite element model of the bridge and the related wind-induced bridge response analyses have been of great value for the present study. We are also very grateful to Dr. Lin Li and Professor Sverre Haver for valuable discussions on the TLP hydrodynamics and the Sulafjord environmental conditions.
Publisher Copyright:
© 2018 Elsevier Ltd
Other keywords
- Coupled analysis
- Finite element analysis
- Floating bridge
- Inhomogeneous waves
- Time domain
- Turbulent wind