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Contemporary aero-structural design frameworks for wind-sensitive bridges are mostly based on the assessment of aeroelastic responses under synoptic winds. However, holistic design methodologies must address all potential wind scenarios, such as non-synoptic wind events and variations in the angle of attack due to complex terrains. This requires the evaluation of the aeroelastic responses considering the sensitivity of the fluid-structure interaction parameters with the angle of attack. Hence, this study proposes a Kriging-based multi-directional aeroelastic surrogate to emulate the flutter derivatives of bridge decks as a function of the deck shape, frequency of oscillation of the deck, and the mean incident angles of wind. This design tool is pivotal to properly modeling the nonlinear features of flutter derivatives at low reduced velocities and their sensitivity with the angle of attack. The aeroelastic surrogate will be later integrated into aero-structural design frameworks for the shape optimization of bridge decks under non-stationary winds.
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This content will become publicly available on May 24, 2026
Aero-structural design of bridge decks under synoptic and non-synoptic winds via aeroelastic surrogates comprising shape, reduced velocity, and mean angle of attack
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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- Award ID(s):
- 2503131
- PAR ID:
- 10642222
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Journal of wind engineering and industrial aerodynamics
- Volume:
- 265
- ISSN:
- 0167-6105
- Page Range / eLocation ID:
- 106133
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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