Model updating based on the dynamic identification of a baroque bell tower

Abstract

The sanctuary of Santa Maria di Loreto (Mola di Bari, Italy) was built in in the sixteen century and it is constituted by a church with a simple hut façade characterized by a fine calcareous rose window and on its left side a high bell tower with heavy bells. In the present study, a non-destructive dynamic identification of the modal characteristics of the structure has been carried out by firstly organising an experimental setup of environmental measurements with several accelerometers placed on different levels of the bell tower. Secondly, the data acquired by the accel-erometers have been elaborated by using modern statistic techniques of operational modal analysis (OMA). Finally, these results have been used for calibrating a complete finite element (FE) model of the bell tower structure that may permit to obtain important information about the state of integrity of the medieval structure. This calibrated model was developed to obtain a preliminary evaluation of the seismic vulnerability of the bell tower by performing a nonlinear static analysis.