Knowledge of the construction technique of the multiple leaf masonry fa\ue7ades of Palazzo Ducale in Venice with ND and MD tests

his paper presents a first program of non-destructive tests carried out on two medieval fa\ue7ades and inside the main rooms of Palazzo Ducale in Venice, i.e. the room of Maggior Consiglio and the room of Scrutinio. A probably multiple leaf load-bearing brick masonry and an external cladding of polychrome stones compose these fa\ue7ades under investigation. The aim of the tests concern the improvement of knowledge about the construction technique and the mechanical features of these important historical facades. The program was set up after a preliminary historic investigation. Non-destructive and minor-destructive investigations (i.e. pattern surveys, endoscopic tests and georadar test) on the inner sides of the two walls of the area under examination were carried out for the analytical determination of the construction technique and structural characteristics, not clearly inferable from the literature. Due to the complexity of the structure and the transformations undergone in seven hundred years of life, and to the very limited investigable areas of the internal surface, the results of investigations cannot be extended to the entire structure. Nevertheless, these tests provide valuable clues to give a correct interpretation of the construction technique and to contribute to identify the possible mechanical properties, which provide knowledge about the health state of the building. \ua9 (2014) Trans Tech Publications, Switzerland