Tehcnological analysis, typological features and seismic vulnerabilities of post-World War II Italian school buildings

Many Italian school buildings, built just after the post-World War II, share similar geometrical and spatial characteristics. Some of these features may negatively affect the building seismic response, generating typical seismic vulnerabilities. In order to mitigate them, and then to foster an effective transition towards a safer and more sustainable society, it is important to provide exemplary cases on how to proceed correctly. For this reason, in this paper typical vulnerabilities of Italian post-World War II RC school buildings are individuated and discussed. For one of the most representative case study an in situ experimental campaign has been carried out in order to identify the specific seismic vulnerabilities related to specific geometrical aspects or material properties. Results of structural assessment have evidenced that some typological vulnerabilities such as wide atriums, eccentric stairs and tall windows, along with irregularity in plan configuration, strongly affect the global seismic behavior of the school buildings. Finally, a structural intervention aimed to improve the performance against seismic actions has been proposed and described for the case study. The intervention concerned RC jacketing of the columns, shear strengthening of beams through Carbon Fiber Reinforced Polymers (CFRP) sheets and strengthening of the beam-columns joints. The strengthening efficiency has been evaluated by means of pushover analysis. The proposed intervention can improve the seismic resistance of the building.