Wind-sensitive bridges are commonly designed based on their aeroelastic responses under synoptic winds. However, a holistic aero-structural design framework must address all potential wind scenarios along the bridge life cycle, including non-synoptic events and synoptic winds with relevant variations in the mean angle of attack due to wind-induced static deck deformation or complex terrain effects. This requires the evaluation of the aeroelastic responses considering the sensitivity of the fluid-structure interaction parameters to the wind angle of attack. Aiming at properly modeling these effects within design frameworks, this study proposes harnessing a multi-directional aeroelastic Kriging surrogate trained with forced vibration CFD simulations to emulate the flutter derivatives as a function of the deck shape, reduced velocity, and mean angle of attack. A bridge deck with a variable depth ranging from streamlined to bluff configurations is studied in detail, showing drastic changes in relevant flutter derivatives. The deck shape drives the impact of the mean angle of attack in some critical flutter derivatives, including the occurrence of A2* sign flipping, with its implications in the torsional stability. The resulting aeroelastic surrogate is conceived to be integrated into aero-structural optimization frameworks for optimally shaping bridge decks under synoptic and non-synoptic wind scenarios.
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Shaping bridge decks for VIV mitigation: A wind tunnel data-driven adaptive surrogate-based optimization method
Vortex-induced vibration (VIV) of deck girders frequently drives the wind-resistant design of wind-sensitive bridges from the preliminary to final design stages. Shaping bridge decks is a proven strategy to mitigate VIV. While significant shape modifications are commonly restricted to preliminary design stages, only minor medications are possible at advanced design stages, typically involving adding flow modifiers or changing the shape and location of existing appendages. These mitigation strategies have been implemented in the last decades by carrying out expensive wind tunnel campaigns and following heuristic design rules. This paper proposes an experimental data-driven adaptive surrogate-based optimization approach to systematically identify optimum deck shapes that minimizes the economic cost of the bridge while fulfilling the VIV project specifications. The methodology is conceived to carry out simultaneously the general and detailed shape design of the final deck configuration by harnessing a sequential sampling plan aiming at reducing the sectional model construction costs. The proposed holistic design framework is successfully applied to a real application case involving 26 wind tunnel tests of 1.8-meter wide sectional models to figure out the optimal gap distance and location of maintenance tracks of a twin-box deck equipped with all the appendages included in the final deck design.
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- Award ID(s):
- 2301824
- PAR ID:
- 10505720
- Editor(s):
- Stathopoulos, Ted
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of Wind Engineering and Industrial Aerodynamics
- Volume:
- 242
- Issue:
- C
- ISSN:
- 0167-6105
- Page Range / eLocation ID:
- 105568
- Subject(s) / Keyword(s):
- Vortex-induced vibrations Wind tunnel testing Long-span bridges Surrogate models Aerodynamic optimization Data-driven design Construction costs
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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