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Controlling wind-induced responses is a challenging and fundamental step in the design of wind-sensitive critical infrastructures (CI). While passive design modifications and passive control devices are effective alternatives to a certain extent, further actions are required to fulfill design specifications under some demanding circumstances. Active countermeasures, such as active dampers, active aerodynamic devices, and operational control systems, stand out as a smart alternative that allows extra control over wind-induced responses of tall buildings, long-span bridges, wind turbines, and solar trackers. To make this possible, CI are equipped with operational technology (OT) and cyber–physical systems (CPS). However, as with any other OT/CPS, these systems can be threatened by cyberattacks. Changing their intended use could result in severe structural damage or even the eventual collapse of the structure. This study analyzes the potential consequences of cyberattacks against wind-sensitive structures equipped with OT/CPS based on case studies reported in the structural control literature. Several cyberattacks, scenarios, and possible defenses, including cyber-secure aero-structural design methods, are discussed. Furthermore, we conceptually introduce and analyze a new cyberattack, the ‘‘Wind-Leveraged False Data Injection’’ (WindFDI), that can be specifically developed by taking advantage of the positive feedback between wind loads and the misuse of active control systems.
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Methodologies to mitigate wind-induced vibration of tall buildings: A state-of-the-art review
This paper reviews the state-of-the-art and –practice on various methodologies developed to control the wind-induced vibration of tall buildings. Tall buildings experience wind-induced vibration in the along- and across-wind directions depending on the wind direction, building shape, height, and structural properties. It is possible to control the wind response of buildings through passive, active, and semi-active systems. Damping systems, which are widely used to reduce the structural vibrations, are reviewed, and their performance in alleviating the building vibration is discussed. It was found that the application of conventional dampers needs to be reassessed to ensure their efficiency in dissipating the energy, especially caused by wind loads. Specific attention has been given to the aerodynamic modification of building shapes considering their effectiveness and high popularity within the wind engineering community. A comprehensive review of the existing wind tunnel experiment and Computational Fluid Dynamics (CFD) studies are conducted here to present the past and recent achievements on the response mitigation of tall buildings. A comparative study on the performance of different systems has been provided that can provide a commencing point for future studies. The existing challenges and their solutions are explained, and suggestions for future studies are proposed. It is expected that the information provided in this paper will facilitate further research in the area of wind-induced vibration mitigation approaches of tall buildings.
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- PAR ID:
- 10176381
- Date Published:
- Journal Name:
- Journal of building engineering
- ISSN:
- 2352-7102
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.jobe.2020.101582
