A nonlinear approach for the simulation of the buffeting response of long span bridges under non-synoptic storm winds

• Published in: Journal of wind engineering and industrial aerodynamics Vol. 247; p. 105681
• Main Authors: Calamelli, Filippo, Rossi, Roberto, Argentini, Tommaso, Rocchi, Daniele, Diana, Giorgio
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.04.2024
• Subjects: Buffeting response; Long-span bridges; Non-synoptic wind; Nonlinear rheological model; Long-span bridges; Nonlinear rheological model; Non-synoptic wind; Buffeting response
• ISSN: 0167-6105; 1872-8197
• DOI: 10.1016/j.jweia.2024.105681

In recent years, extreme atmospheric events are becoming increasingly frequent and unpredictable. These phenomena are often characterized by low-frequency variations of the wind speed and angle of attack, mainly due to large-scale turbulence. These features can be critical for long-span bridges as they can lead the deck in conditions where the nonlinear effects of aerodynamic forces are enhanced. Therefore, it is increasingly important to develop reliable numerical tools to simulate the response of these structures to non-synoptic winds. In this work, a nonlinear rheological model that is able to account for the large variations in wind speed and angle of attack is employed to investigate the dynamic response of two different bridges subjected to two different wind fields. The first scenario is a standard synoptic wind field used as a baseline. On the other hand, the second wind scenario represents an extreme non-synoptic atmospheric event. The results highlight how the nonlinear effects of the aerodynamic forces, in particular those related to the large variation of the angle of attack, could lead to significant changes in the bridges’ response. These effects would not be captured by employing standard linearized methods. •Non-synoptic atmospheric events exhibit low-freq variations in wind speed and angle of attack.•Related nonlinear aerodynamic effects strongly influence the response of long-span bridges.•A nonlinear rheological model able to include these effects is presented.•The model helps to assess the behavior of bridges under extreme atmospheric events.