The use of an integrated approach for building inventory and effects on risk estimations at the territorial scale

Large-scale seismic risk assessment is probably the most appropriate tool for investigating the consequences of earthquakes in a region of interest. Most of the existing risk-oriented studies focus on the seismic hazard evaluation and vulnerability assessment, while fewer efforts were performed in evaluating the influence of exposure modelling. The large-scale building inventory is generally conducted by relying on readily available sources of information, such as databases based on census data. However, the information contained in census databases are often limited to poor level data, such as building construction material, construction age and (not always available) the storey number. The use of inventory data for large scale application requires suitable rules to assign buildings typologies to vulnerability classes, that is an exposure model. Most of the existing exposure models are calibrated on building typological data available from post-earthquake survey data and therefore are based on data from specific geographic areas, namely the ones hit by damaging earthquakes. It is known that the distribution of building typologies can vary greatly for different areas of a country and the availability of construction material in the area. Furthermore, the evolution of construction techniques and the codes in force at the time of construction may affect the presence of a particular building's typology rather that another one. This study aims to evaluate the influence of a better knowledge level of the building environment on seismic risk at regional scale, investigating the variability of masonry building typologies distribution. The application is presented for two different Italian regions, showing that an improved characterization of regional vulnerability may strongly influence the impacts in terms of risk estimations