High resolution operational modal analysis of Sant’Agata del Mugello in light of its building history

The building history of a cultural heritage and the after-effects induced by extreme loads such as earthquakes have durable impact on its modal parameters. This article aims to discuss peculiarities some parameters extracted from ambient vibration measurements in light complex Sant’Agata del Mugello. Romanesque church located Mugello basin (Tuscany, Italy) suffered many earthquakes, at least 1542. In this context, we carried out two dense campaigns March June 2019. We each mode’s natural frequency, mode shape, damping using Enhanced Frequency Domain Decomposition. identified ten modes. Some modes highlight structural singularities related church: rocking base bell tower; phase opposition between tower nave; bending walls nave. Since instrumentation benefited vast number recording positions (83), tested sensor placement strategy resolution specific case higher-order decreases strongly degraded impacting dynamic analysis church.