A rapid seismic classification of historic masonry buildings with risk matrices

The Italian historical heritage is exposed to significant environmental risks. One of them is the seismic risk. The different seismic hazards of the Italian territory require the study of vulnerability assessment methodologies, which can be of a rapid nature and applied at different scales: from the building, to the aggregate, to the municipality. The aim of such methods is not to provide an exhaustive classification of the actual structural deficiencies of each building studied, but rather to point out the more or less serious criticalities within a historical heritage at the territorial level, and can therefore become a useful tool for establishing priorities and methods for more targeted intervention and protection. With this in mind, two different survey methodologies were developed, which can be considered complementary, whose application to masonry residential buildings seems to be able to produce vulnerability pictures at different scales. The data required for the application of these methodologies are data available in national and municipal databases, in particular from the DPC-Reluis-Cartis database. The methodologies were tested in different hazard contexts: at urban scale, at building type scale and at building scale. The proposed methodologies concern: the creation of a map of the historical centre, provided by the municipality, with an indication of the seismic vulnerability class of the buildings (low, medium and high), obtained from the data of the Reluis-CARTIS protocol, and the construction of fragility curves describing the probability of reaching and exceeding a certain threshold of loss of performance when the local seismic stress varies.