PSI - Issue 78

Alessandro Fulco et al. / Procedia Structural Integrity 78 (2026) 2054–2061

2061

5. Conclusions The illustrated seismic isolation intervention allows for the seismic retrofitting of the structure in accordance with NTC 2018, increasing its seismic-resistant performance. The isolation allows the achievement of the performance levels of seismic retrofitting of the structure, considering a class of use IV, corresponding to "Buildings with important public or strategic functions also with reference to civil protection management". The numerical analyses carried out showed the fulfilment of all the verifications for all the expected limit states. This result was made possible by the decoupling effect given by the seismic isolation system with a reduction in base shear of about 8 times compared to the ante-operam conditions. Moreover, compared to the ante-operam status, the isolation system allowed a drastic reduction in floor accelerations and relative drifts, eliminating any damage states not only at SLD and SLO limit states, and practically avoiding them even at SLV and SLC limit states. The intervention carried out is characterised by the innovative nature of the design strategy implemented, which ensures not only the safe structural performance but also the operation during seismic events of considerable intensity, thus making the building suitable to maintain its functions as a strategic building. In conclusion, it was possible to achieve performance levels higher than the conventional ones required for ordinary buildings, such as to make the expected consequences in terms of damage and inactivity following seismic events substantially negligible, conferring a considerable increase in value to the entire construction and the activities carried out in it. All the main planned works already carried out or still in progress allowed and are still allowing the full use of the building without any kind of interruption of strategic activities carried out within. The adopted intervention strategy stands as a reference design solution for the seismic capacity increase of strategic buildings in order to maintain operational functions during and after the construction activities. References Park, Y. J., Wen, Y. K. and Ang, A. H., 1986. Random vibrations of hysteretic system under bi-directional ground motions, Earthquake Engineering and Structural Dynamics, 14, 543-557. EN15129, Anti-seismic devices. CEN, Brussels, 2009 Fagotti, G., Nodessi Proietti, S., Soccodato, F., Alemanno, N., Rotondi, M., Mezzi, M., Verducci, P., Bavicchi, M., Ciavaglia, C., Cincini, L., Finotto, M., Gabbarelli, E., Morosia, F., Di Carlo, S. 2022. The integrated project for the post-earthquake reconstruction of Castelluccio di Norcia: procedures, techniques, implementation, XIX ANIDIS. Torino. Mezzi, M, Comodini, F., Fulco, A 2019. Isolamento sismico a grande scala per la salvaguardia del tessuto urbano nella ricostruzione post-sisma, Convegno ANIDIS, Ascoli Piceno (IT). Fulco, A., Mezzi, M., Comodini, F. 2020: Practical procedure to assess the expected consequences of earthquakes on buildings, Procs. 17thWCEE, Sendai. Japan. Martelli, A., Forni, M., Bettinali, F., Bonacina, G., Bergamo, G., Castellano, M.G., Medeot, R.,Marioni, A., Sanò, T., Pugliese, A., 1999. New Activities Performed in Italy on Innovative Anti-SeismicTechniques for Civil and Industrial Structures. Proc. ASME-PVP Conf., Boston, USA, PVP-Vol. 387 pp. 311-326. Mezzi, M. and Petrella, P. , 2013. Experiences from the Reconstruction After the 2009 L'Aquila Earthquake. Damage, Vulnerability, Retrofitting, ISEC-7 New Developments in Structural Engineering and Construction. Honolulu, USA. NTC2018. Norme Tecniche per le Costruzioni D.M. 17 gennaio 2018, Consiglio Superiore dei Lavori Pubblici, GU Repubblica Italiana, Roma. Ubertini, F., Comodini, F., Fulco, A., Mezzi, M., 2017. A Simplified Parametric Study on Occupant Comfort Conditions in Base Isolated Buildings under Wind Loading, Advances in Civil Engineering, Hindawi Publishing Corporation, Article ID 3524975, 13 pages