Operational Modal Analysis for Seismic Protection of Structures

This thesis focuses on output-only modal identification tests and on the opportunities they provide in the field of seismic protection of structures. The problem of a good measurement process, in order to obtain high quality data and reliable results, is investigated. Reliability of estimates is assessed above all towards the problem of damping estimation, due to the fundamental role it plays in determining the structural response to dynamic loads, such as earthquakes. Specific attention is focused on the relationship between experimental tests and numerical modelling, and on the opportunities given by model updating procedures in the field of earthquake engineering. Finally, an algorithm for fully automated modal parameter identification and tracking is described, pointing out the importance of Operational Modal Analysis in the field of Structural Health Monitoring.