Dynamic behaviour of UHPFRC arch bridge Wild

Bridge "Wild" is the first UHPFRC bridge in Austria. This paper shows first results of dynamic monitoring on the bridge, including one year of data. A simple automated frequency identification algorithm in frequency domain is described, which operates without user interference. Measurement data is analysed in terms of temperature dependence of eigenfrequencies and damping values. Eigenfrequencies show typical negative correlation with temperature, while damping values show different pattern. The temperature-driven changes are analysed numerically using finite element model. Major parameter in this analysis was stiffness of asphalt concrete layer, as it can be concluded by comparison with measured frequency changes.