The importance of analyzing structures subjected to wind action, particularly dynamic wind loads, had risen drastically after the collapse of the Tacoma Narrows Bridge in 1940. Be- fore that, wind action was mostly considered to be static due to the complexity associated with describing dynamic wind loads. Eurocode 1 provides analytical methods to analyze dy- namic wind loads, but only for simple geometrical sections. Which clearly does not provide a wide spectrum for its usage, considering the fast-paced advances in civil engineering and the tendency to construct lighter and slenderer structures. Alternatively, numerical methods such as CFD have shown great potential in analyzing wind action on geometrically complex structures. However, they are associated with a considerably long computational time. This research work aimed at devising a new methodology for calculating dynamic wind loads on line-like structures. The proposed method objective is to shorten the computational effort and time needed to complete the necessary steps of the Davenport wind load chain. The target reduction in effort is focused on the aerodynamic effects of the chain. This is accom- plished by a synthetic and direct generation of dynamic wind loads that vary both temporally and spatially. The synthetic generation of the loads is based on a stochastic method that re- quires as an input few basic intrinsic information about the structure of interest. Among them are the mean and standard deviation of the aerodynamic loads and the Strouhal number. The Volgograd bridge in Russia which had experienced severe oscillations due to vortex shedding in 2010, was chosen as an example application for the proposed method. The first step was to conduct a CFD simulation on only a sectional model of the bridge to extract the necessary input information for the proposed method. Secondly, the synthetic drag, lift, and moment loads were generated based on the input data. The synthetic loads incorporated the correlation aspects of the wind loads and the effects of vortex shedding by adding the contribution of its frequency to the synthetic lift and moment load signals. Finally, a struc- tural simulation was completed based on a 1D beam representative model of the Volgograd bridge. The bridge’s response and the influence of adding mass tuned dampers were inves- tigated through three scenarios: The bridge without dampers on it, the bridge with dampers on only one of its longest spans, and finally the bridge having dampers on three of its longest spans. The proposed method showed great potential in terms of applicability and reducing the time needed to analyze wind action on structures. The synthetic loads took around 10 hours to generate while the CFD simulation on only a sectional model took around 10 days, which would have been much longer if the full model of the bridge was to be simulated as part of the FSI workflow. Furthermore, the response of the bridge to the dynamic loads did show a significant drop in the standard deviation of the displacement. Namely, 38% and 64% when installing the dampers on only 1 span and then in the scenario of having the dampers in all 3 spans acting as semi-active tuned dampers, respectively. Further development and investigations of the proposed method in this research, could embark on a potential of a new approach to analyzing wind action on structures.     «

The importance of analyzing structures subjected to wind action, particularly dynamic wind loads, had risen drastically after the collapse of the Tacoma Narrows Bridge in 1940. Be- fore that, wind action was mostly considered to be static due to the complexity associated with describing dynamic wind loads. Eurocode 1 provides analytical methods to analyze dy- namic wind loads, but only for simple geometrical sections. Which clearly does not provide a wide spectrum for its usage, considering...     »