Stress ribbon bridges and footbridges are specific and technologically demanding structures which, due to their slenderness, are susceptible to vibrations resulting from dynamic excitation caused by pedestrian and runner activity. Their dynamic response is highly dependent on temperature changes that affect the stiffness of the structure, as well as on damping, which is difficult to estimate accurately in advance. This article examines the influence of temperature variations and damping on the vibrations of a stress ribbon footbridge and, consequently, on user comfort. The case study of these effects 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 article also presents a numerical model of the analysed footbridge, with its response compared to the measured static and dynamic response of the actual structure. Furthermore, the findings of extensive parametric dynamic analyses are presented, performed under varying temperature conditions and considering different ratios of critical damping.
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