Dynamic Behavior of a Medieval Masonry Bell Tower. Part I: Experimental Measurements and Modeling of Bells Dynamic Actions

The work described herein was conducted within the framework of an ongoing research program on the dynamic behavior of the Tower of Matilde, the bell tower of the Cathedral of San Miniato, Pisa, Italy, an interesting case study for its current structural arrangement and the modifications it has undergone over the centuries. This paper (Part I) details the experimental analyses performed in order to obtain an accurate measure of both the motion of the towerʹs bells and, consequently, the time function of the dynamic actions transmitted to the tower during their motion. We then demonstrate how it is possible to arrive at an accurate, even though approximate, analytical description of both the bellsʹ motion and their actions by means of only a few experimental measurements and a simple mechanical model (also called in the following additional mass model).