Georadar investigations and monitoring of the wall structures and vault system of the Sala delle Asse, in Leonardo da Vinci - The Sala delle Asse of the Sforza Castle

In 2011, the engineer Giuseppe Albano studied the geometry and state of conservation of the structures of the vault system of the Sala delle Asse to assess any damage and instabilities in the room and proposed a series of studies and monitoring for the cracks that had been detected on the extrados of the lower vault and on the vertical structures, with the aim of identifying any movement that might be un­der way. Currently, a diagnostic campaign is in progress, targeted towards understanding the build­ ing technique and structural behaviour of the vault system. Radar studies were conducted to reconstruct the stratigraphy of the system comprising the lunetted cloister vault, the depressed arch cloister vault above and the floor of the room on the upper floor. Other radar studies were conducted to characterize the raised wall structures, which are of notable thickness (even as much as aver 2.5 m) and to identify cavities and a flue that runs along the full height of the north-east wall. A topographical/diagnostic laser scanner survey will make it possible to reveal the critical points of the structures and types of instability and provide understanding of the dynamics of the crack pattern. The stratigraphic reading will make it possible to codify the archaeological sequence of the built structure, the deterioration and state of damage (the contribution The Diagnostic Survey: The Sala delle Asse and its Context in the present volume).The need to speed Up the time spent collecting information that would be useful for safeguarding and protecting the room forced the immediate installation of a system far monitoring cracks based on the information available at the time, which derived from a preliminary survey and the results of thermographic studies (see the contribution The Preliminary Thermo-Hygrometric Research and Environmental Monitoring of the Sala delle Asse in this volume), which revealed a few structural cracks. It will be possible to review or integrate the arrangement of the transducers based on the results of the above-described survey.