Pre-diagnostic prompt investigation of a historic Bell Tower by visual inspection and microwave remote sensing

The paper presents the results of a prompt investigation programme carried out on the Bell Tower of the Church Santa Maria del Carrobiolo in Monza. A preliminary documentary research and a series of accurate and systematic visual inspection on site highlighted a weak structural layout of the bell-tower and diffuse damage. The recent construction of an underground car park has triggered the movement of the several cracks. In order to assess the state of preservation of the structure a prompt dynamic investigation was carried out recording the response to ambient vibrations induced by wind, micro-tremors and swinging of bells by microwave interferometers. The preliminary results of the investigation suggest the installation of a static monitoring of the main cracks.