Asociación Española de Ingeniería Sísmica Girona, 8-11 mayo 2007 THE VULNERABILITY ASSESSMENT OF CURRENT BUILDINGS BY A MACROSEISMIC APPROACH DERIVED FROM THE EMS-98 SCALE Alberto Bernardini Dipartimento di Costruzioni e Trasporti, Università degli Studi di Padova, Italia. Sonia Giovinazzi Department of Civil Engineering, University of Canterbury, New Zealand. Sergio Lagomarsino, Sonia Parodi Dipartimento di Ingegneria delle Costruzioni, dell’Ambiente e del Territorio, Università degli Studi di Genova, Italia. sergio.lagomarsino@unige.it SUMMARY A hierarchical family of Damage Probability Matrices (DPM) has been derived in this paper from the ones implicitly contained in the EMS-98 Macroseismic Scale for 6 vulnerability classes. To this aim the linguistic definitions provided by the scale, and the associated fuzzy sub-sets of the percentage of buildings, have been completed according to reliable hypotheses. A parametric representation of the corresponding cumulative probability distributions is moreover provided, through a unique parameter: a vulnerability index variable in the range from 0 to 1 and independent of the macroseismic intensity. Finally, an innovative macroseismic approach allowing the vulnerability analysis of building typologies is defined within the European Macroseismic Scale (EMS-98) and qualitatively related to the vulnerability 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 behaviours with respect to the one generally considered for the typology. Fuzzy measures of any damage function can be derived, using parametric or non- parametric damage probability matrices. For every result of the seismic analysis, the procedure allows supply to the user of the final uncertainty connected with the aforementioned fuzzy relation between the probability of the damage grade, the macroseismic intensity and the vulnerability classes. Keywords: Ordinary buildings, Vulnerability assessment, Damage scenario Introduction Definitive publication in 1998 of the new European Macroseismic Scale (Grunthal 1998), stimulated the elaboration of new methodologies for the development of damage scenarios to the urban fabric (for earthquakes of predetermined intensity) or risk assessments in relation to the ascertained shakeability of the areas. In said methodologies, generally identified with the adjective “macroseismic” ”(Giovinazzi and Lagomarsino 2004; Giovinazzi and Lagomarsino 2006), the conventional vulnerability measures (the 6 vulnerability classes) and the damage grade are directly assumed from the scale, together with the list of the building typologies (possibly modified taking into account the local particularities). The applications carried out are characterised by the different territorial scale (suburban, urban, municipal or regional) and by the different catalogues used for the systematic or sampled classification of the building typologies present in the territory. In particular numerous applications are based on poor but systematic data (in particular ISTAT