Assessing seismic risk in typical Italian school buildings: From in-situ survey to loss estimation

The seismic assessment of existing school buildings is of paramount importance to protect the lives of occupants and manage post-earthquake response and recovery. The collapse of a primary school during the 2002 Molise earthquake in Southern Italy increased the awareness of the need to better understand the potential vulnerability of the existing Italian school building stock. To this end, a recent research project entitled “Progetto Scuole”, whose main objective was to assess the seismic risk of a number of representative school buildings, was carried out at the Eucentre Foundation, in collaboration with the University School for Advanced Studies IUSS, in Pavia, Italy. The results of this project and of the subsequent research conducted by the authors are discussed in this paper, starting with the compilation of a school building database, focusing on the structural typology, the geometrical configuration and the time of construction. Three schools, representative of the Italian school building stock, were then analysed in detail through advanced numerical models developed using information collected during in-situ inspections and calibrated with the results of ambient vibration measurements. Two site locations were chosen to perform probabilistic seismic hazard analysis and select hazard-consistent ground motion record sets adopting the seismicity model used for the calculation of the Italian national seismic hazard map currently in place. Expected annual loss was used as a performance parameter to quantify the seismic vulnerability of the school buildings. Furthermore, the results of the detailed loss estimation were compared with the outcome of the seismic risk classification guidelines, recently introduced in Italy, applied to these same buildings. Finally, this paper presents a preliminary extension of the results to estimate the seismic risk of school buildings of the same typologies if located throughout the Italian territory.