PSI - Issue 44

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2022) 000–000

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ScienceDirect

Procedia Structural Integrity 44 (2023) 472–479

© 2023 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 the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. Abstract The paper discusses issues about the finite element modelling of steel eccentric braces with vertical shear links used as hysteretic dampers to improve the seismic performance of existing reinforced concrete (RC) buildings. To this end, eccentric bracing systems have been designed for seismic upgrading of a case-study existing RC school building in Italy. Multiple finite element modelling approaches are described, using both frame and shell finite elements, various steel stress strain relationships, as well as including both geometrical imperfections and residual stresses. Numerical models were built using two commercial structural analysis programs, SAP2000 and Ansys , and one open-source software, Code_Aster . The numerical study allowed to (i) quantify values of the plastic overstrength factor of the considered shear links; (ii) evaluate the overall system stability and general inelastic response; (iii) compare various modelling approaches. © 2022 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 the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy Keywords: Damper; RC building; Retrofitting; Steel; Upgrading 1. Introduction Steel eccentric braces with vertical shear links (denoted as Y-bracing) might be a useful option to reduce the seismic vulnerability of older reinforced concrete (RC) buildings. In fact, the system allows increasing the building stiffness and resistance, as well as ductility (Ghobarah and Elfath (2001), Barecchia et al. (2006a), Mazzolani et al. (2009), Della Corte et al. (2013)). The use of yielding links allows to limit the additional forces introduced into the existing structure, thus avoiding, or reducing any additional local retrofitting of RC elements (Cantisani et al. (2021), Mazzolani et al. (2022)). The use of short links is usually preferred because they allow maximizing the increase of 022 The Authors. Published by ELSEVIER B.V. XIX ANIDIS Conference, Seismic Engineering in Italy FEM Analysis of Steel Eccentric Braces for Seismic Retrofitting Gaetano Della Corte a *, Gaetano Cantisani a a Department of Structures for Engineering and Architecture, University of Naples Federico II, Via Claudio 21, Naples 80125, Italy te a a

* Corresponding author. Tel.: +39-081-7683131 E-mail address: gaetano.dellacorte@unina.it

2452-3216 © 2022 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 the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy

2452-3216 © 2023 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 the scientific committee of the XIX ANIDIS Conference, Seismic Engineering in Italy. 10.1016/j.prostr.2023.01.062