COMPARISON OF BUILDINGS DESIGNEDTO EUROCODE 8 AND TO ITALIAN SEISMIC CODEFOR VULNERABILITY AND RISK ASSESSMENT

摘要

The current Italian seismic design code is a mandatory regulation, based on traditional andrather simple prescriptions. Eurocode 8, that should be adopted in Italy in few years, is basedon rather different and more complex criteria. A vulnerability and risk analysis, in which theexpected increment of the construction cost is compared with the expected decrement of thebuilding damageability, will support calibration and implementation of the new code by thelocal authorities. To this purpose, three different types of buildings have been designed bothwith Italian and EC8 seismic codes. For each kind of buildings the following parameters havebeen varied: the seismic action level and, for EC8, the ductility level. For each designedbuilding the analysis of the construction cost has been performed in terms of cost incrementwith respect to the non seismic design and a simplified model have been set up for thecalculation of the fragility curves. Connecting these results with available hazard studies, themean expected value of the damage level has been evaluated for each Italian municipality andfor each kind of building. Comparisons between the two codes in terms of costs anddamageability, for different ductility levels pertaining to the same code (EC8) are drawn.While the EC8 low-ductility buildings showed a vulnerability reduction with acceptable costincrements, some difficulties in the design and construction seem to be the most criticalaspects of the implementation.