PSI - Issue 78

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 78 (2026) 17–24

© 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of XX ANIDIS Conference organizers Keywords: school building; precast reinforced concrete; retrofit; dissipation devices; bracing frames. The proposed intervention includes the installation of external steel braced frames equipped with energy-dissipating devices. These frames increase the building's stiffness, thereby reducing displacements of structural elements. The corresponding increase in acceleration is offset by the dissipation of seismic energy through the installed devices. The positioning of the steel frames along the building perimeter is chosen to regularize seismic behavior by minimizing the eccentricity between the center of mass and the center of rigidity, thereby reducing the resulting torsional effects. In addition, local strengthening interventions are proposed, like those increasing the shear strength of beams and establishing a mechanical connection between the precast beams and columns, whose current interaction relies solely on friction. 1. Introduction The preservation of built heritage is of paramount importance for ensuring human safety, especially in the case of school buildings. Seismic events in recent decades have underscored the high vulnerability of the Italian building stock to earthquakes. This vulnerability is commonly associated with insufficient lateral strength and stiffness in both principal directions, low torsional stiffness, inadequate seismic detailing of structural components, and the presence 2XX ANIDIS Conference External steel bracing frames with energy dissipation devices for the seismic retrofit of a precast R.C. school building Giada Frappa a, *, Alessia Bernardotto a , Samantha Lisetto a , Margherita Pauletta a a University of Udine, Polytechnic Department of Engineering and Architecture, Via delle Scienze 206, 33100 Udine, Italy Abstract This study presents a retrofit solution for a school building located in a high seismic risk area. The as-built structure, composed of precast concrete elements, lacks sufficient strength to meet the seismic and gravitational load requirements set by the Italian Building Code.

* Corresponding author. Tel.: +39-0432-558065 ; fax: +39-0432-558052 . E-mail address: giada.frappa@uniud.it

2452-3216 © 2025 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of XX ANIDIS Conference organizers 10.1016/j.prostr.2025.12.003