Vulnerability and damage assessment of current buildings in Italy: an application to Sulmona Town

A macroseismic method for the vulnerability assessment of current buildings and an application to the town of Sulmona (Italy) are presented in this paper. The method is derived making reference to the EMS-98 Macroseismic Scale, which implicitly contains a model of vulnerability. Fuzzy measures of Damage Probability Matrices (DPM) have been derived from the qualitative and incomplete relative frequencies contained in the EMS-98 Scale for the six vulnerability classes (from A to F). Moreover, a useful simplified parametric representation of the corresponding sets of probability distributions of the damage is provided adopting a unique parameter independent from the macroseismic intensity, which can be recognised as a vulnerability index. With reference to the building typologies defined in the EMS-98 scale, the associated Damage Probability Matrixes have been derived interpreting the correlation suggested by the scale with the vulnerability classes, in terms of relative frequencies of the classes. Bayes' theorem allows the upgrading of the frequencies when further data about the built-environment or specific properties of the buildings are available, allowing the identification of a different behaviour with respect to the one generally considered for the typology. Fuzzy measures of any damage function can be derived. For every result of the seismic analysis, the procedure allows supplying to the user the final uncertainty connected with the aforementioned uncertainties. This macroseismic method can be employed on the basis of poor statistical existent data (such as ISTAT national census data) or information properly surveyed. Furthermore, it can be implemented both for the vulnerability assessment of single buildings and of built-up areas. Implementations of the method are carried out for ordinary buildings in Sulmona (Italy) considering the 14th ISTAT national census data and the information collected building by building in a field survey. With reference to the ISTAT data, the interpretation of this base of information for the vulnerability assessment of buildings is presented.