PSI - Issue 78

Available online at www.sciencedirect.com

ScienceDirect

Procedia Structural Integrity 78 (2026) 349–356

© 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: Light-frame timber structures; Top additions; Dissipative braces; Pressurized Fluid Viscous Dampers Abstract The paper presents the first section of a research study on light-frame timber structures to be installed on top of reinforced concrete (RC) buildings. The study has a dual objective: to evaluate the possibilities offered by traditional “platform-frame” interventions, and explore new configurations based on the incorporation of small-sized supplemental damping systems, easily hidden behind the oriented strand board sheathing panels of the light-frame structure. A representative real case study was selected for the application of the two structural solutions, consisting of a two-storey RC residential building, characterized by an eccentric position of the RC core surrounding the stairwell. This layout determines a remarkable irregularity in plan and thus significant seismic torsional response effects, making the examined case particularly challenging. The single-storey addition covers approximately 70% of the flat roof level. The paper reports: a seismic assessment analysis of the building in current conditions; the modelling criteria and the design of the light-frame timber superstructure in the traditional configuration and in the presence of the supplemental damping system, consisting of dissipative braces incorporating small-sized pressurized fluid viscous spring-dampers; and comparisons between the seismic performance of the superstructure and the entire building under the two different design hypotheses. XX ANIDIS Conference Conventional and supplementally damped light-frame timber top additions of RC structures Stefano Sorace a, *, Naisa Hoxha a , Arianna Straulino a , Gloria Terenzi b a Polytechnic Department of Engineering and Architecture, University of Udine, Via delle Scienze 206, 33100 Udine, Italy b Department of Civil and Environmental Engineering, University of Florence, Via Santa Marta 3, 50139 Florence, Italy

* Corresponding author. Tel.: +39-432-558056; fax: +39-432-558052. E-mail address: stefano.sorace@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.2025.12.045