Stress ribbon bridges and footbridges represent a specific and technologically demanding type of structure, composed of slightly sagging tensioned cables embedded in a reinforced concrete slab. Compared to their large span, the slab is extremely thin, giving the bridges an elegant and lightweight appearance. However, this also makes them more susceptible to vibrations induced by pedestrians through dynamic forces. Excessive vibrations may cause discomfort and even emotional reactions among users. In addition, such bridges are highly sensitive to temperature variations, which affect their stress-strain state and consequently the stiffness of the structure. Stiffness is one of the key properties determining the bridge’s response to dynamic loading. Besides stiffness, the dynamic response is also influenced by structural damping, a complex phenomenon that can only be accurately characterized through measurements performed once the bridge is fully constructed. The aim of this master thesis was to investigate the influence of temperature changes and damping on the vibrations of stress ribbon footbridge, and consequently on user comfort. The study was conducted on the pedestrian and cyclist bridge over the Krka River in Irča vas near Novo mesto, which is the first and currently the only structure of this type in Slovenia. The central part of the thesis focuses on the development of a numerical model of the footbridge using SOFiSTiK 2024 software, validation of the model with measured static and dynamic responses, and the execution parametric dynamic analyses by varying parameters related to temperature changes and damping ratio.
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