Description
The development of accurate finite element (FE) models of existing bridges represents a challenging issue due to the uncertainties on boundary conditions (e.g., friction of the supports and their behavior with the traffic loads, out of plumb of pylons, soil-structure interaction, etc.), material properties and damping estimations. Full-scale measurements are usually employed for updating a preliminary FE model through deterministic methods, although probabilistic approaches should be preferable due to the non-negligible uncertainties present in both modeling and measurements. This work deals with the Bayesian FE-model updating of a curved approaching span of the Indiano Bridge (Florence, Italy) through full-scale vibration tests. The case study is represented by a steel/concrete composite deck slab bridge with a span of about 25 m. The deck has been equipped with both a wireless accelerometer network and wired sensors, to increase the number of measuring points and to compare the results of the two sensor typologies. A procedure based on the Bayes theorem has been developed and tested on the considered case study incorporating both model uncertainties and measurement errors. The work also includes strain measurements on the anti-lift devices, consisting of steel bars, employed to avoid the overturning of the curved deck. The bars have been equipped with strain gauges and their deformation has been recorded along with the vibrations detected by the accelerometers installed.
