A rapid method to census the seismic risk class of masonry buildings

Ministerial Decree 65/58 and its Guidelines, published in 2017, allow the seismic risk classification only of masonry buildings, associating with their vulnerability class their location within the four seismic zones into which Italy has been divided since 2003. Therefore, if the masonry type and structural weaknesses of a building are known, it is possible to assign the corresponding vulnerability class to it and to census, by means of a rapid onsite survey, the seismic risk class of a very large number of masonry buildings. Based on this assumption, a method has been developed for a single operator to rapidly determine the masonry type and structural weaknesses of a building. The survey was conducted by recording this information in alphanumeric tables divided into fields whose attributes were preliminarily chosen and inserted in data dictionaries that could be brought up with drop-down menus. At the end of the survey, the contents of the tables were transferred to a relational database, incorporated in a geographical information system, filtered and processed to obtain the vulnerability class of each building represented on the same basic numerical cartography used during the survey. By associating the seismic zone with the building, the corresponding class was calculated. The method made it possible to census the seismic risk class of 400 masonry buildings in a municipality with an extension of ca. 20 km2 in less than two working days. This highlights the possibility of extending it to larger areas to estimate, assess or manage the effects or the emergency phase of an earthquake.