Preliminary dynamic characterization of the city walls of Pisa (Italy) through ambient vibration testing

Urban walls enclosing the historic center of medieval towns are of considerable significance from both historical and structural perspectives, and ensuring their safety is a major challenge in cultural heritage conservation. Recent studies have employed ambient vibration measurements to investigate their dynamic behaviour, with particular attention to the characterization of materials and boundary conditions. This paper presents preliminary results from an experimental campaign conducted on the ancient city walls of Pisa. The presence of an isolated gate section provided a valuable opportunity for a first stage of investigation aimed at characterizing the masonry materials, also informed by historical and construction analyses. The findings demonstrate the potential of the proposed approach and represent an initial step towards improving understanding of the structural response of these heritage structures.