Seismic vulnerability assessment of the Museum of the Vasari's House in Arezzo

The paper discusses on the seismic assessment of the Vasari’s House museum in Arezzo (Italy). The museum was investigated within a research project, promoted and financed by the MIBACT (the Italian Ministry for the Heritage, Cultural Activities and Tourism), and the paper aims to show the methodology employed to develop the knowledge process and to evaluate the seismic risk of the Vasari’s House. The building is a three-storey masonry construction composed of disordered stone and brick masonry walls. Floors were realized with different typologies: masonry vaults at the lower levels, wooden and steel floors at the upper ones. The current configuration is the result of an historic process composed of several structural interventions which have partially modified the original layout of the building. To evaluate the historic, geometric and mechanical parameters required to perform a reliable seismic assessment, a detailed and careful knowledge process was developed. Thermal camera inspections, laser scanner survey and other not invasive techniques such as non-destructive in situ investigations (local removals of the plaster on the walls, when possible, drilling resistance measurement tests on the mortar joints by using an instrumented drilling system, single and double flat jack tests for the identification of the elastic properties of the masonry) have allowed to reach a good level of knowledge of the structure giving effective information for the subsequent analyses. The seismic vulnerability assessment was developed according to the Italian "Guidelines for the assessment and mitigation of the seismic risk of the cultural heritage" that identify a methodology of analysis based on three different levels of evaluation, according to an increasing level of knowledge. In particular, herein both local mechanisms and global behaviour were investigated and analysed assuming different structural configurations based on the degree of connection between the structural elements as observed during the knowledge process. The paper, through the discussion of an emblematic case study, aims to highlight the importance of the level of knowledge for the seismic assessment of an historical building.