Monitoring activity on Fiorenza node of A4 Highway

The purpose of this dissertation is the definition of the relevance of the monitoring process on the infrastructures present in Italy. This permit to monitor the changes present in some structural elements or in the overall structure. Firstly, the proper natural frequencies of the structure that have been defined from the acquisition process of the acceleration in the three main directions will be presented. These acquisitions are made by accelerometer which have been installed on the bridge in different points of its span. The acquisition made by them are not continuous, but they are made at a specific time interval. After, a FEM of the overall structure have been made. For this model, the modal analysis has been performed. So, the proper natural frequencies have been defined in the vertical, longitudinal and transverse direction. Sometimes, the Finite Element model is difficult to be defined. This could happen in the cases where the drawings of the analyzed structures are not fully defined or when they have been lost. So, another typology of analysis will be developed. Is the Operational Modal Analysis, which permit to define the modal parameters of the structure. This type of analysis is an output-only method, that means that for performing the analysis, only the response of the structure is need, and not the input forces. Finally, the different obtained frequencies with these three procedures will be compared, in order to understand if this type of monitoring process can be or not efficient. So, in this way it will be possible to establish if even with a lower budget, the monitoring process can give an efficient response.