PSI - Issue 44

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

www.elsevier.com/locate/procedia www.elsevier.com/locate/procedia

Procedia Structural Integrity 44 (2023) 966–973

© 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 Beam-column joints in existing Reinforced Concrete (RC) buildings are usually characterized by the absence of transverse reinforcement. The observation of post-earthquake damage, as well as several numerical and experimental studies, have soundly demonstrated the possible impact of the response of unreinforced joints on the damage – up to collapse – of existing RC buildings under seismic action. In this study, a possible strengthening approach for these elements, based on CAM ® technology, is investigated through experimental tests. The results of these tests are reported, along with the results of a previous experimental campaign carried out on the same topic. Full-scale external beam-column joint specimens are tested, with and without strengthening, and with different characteristics in terms of amount of beam longitudinal reinforcement and concrete compressive strength. Different failure modes are observed for the as-built specimens (joint failure without (J) or after (BJ) beam flexural yielding). The effectiveness of the adopted strengthening approach is demonstrated, observing an increase in joint shear strength and subassemblage ductility and – unless a joint failure in compression occurs – a possible modification of the failure mode into a ductile, flexure-controlled response of the subassemblage, as for code-compliant beam-column joints. © 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: existing buildings; seismic loading; reinforced concrete; beam-column joints; strengthening; experimental results XIX ANIDIS Conference, Seismic Engineering in Italy Experimental Analysis of the Effectiveness of Pre-Stressed Steel Strips for the Strengthening of Beam-Column Joints in Existing RC Buildings Maria Teresa De Risi a *, Paolo Ricci a , Gerardo Mario Verderame a a University of Naples Federico II, via Claudio 21, 80125, Naples, Italy Abstract Beam-column joints in existing Reinforced Concrete (RC) buildings are usually characterized by the absence of transverse reinfor ement. The observatio of post-earthquake damage, as well as sev ral numeric l nd experimental studies, have soundly d m nstrat d the possible impact of the response of unreinforced joints on the da age – up to collapse – of existing RC buildings under eismic acti n. In this s udy, a possibl stre gthening approach for these lements, based on CAM ® technology, i i vestigated through experimental tests. The results of these tests are reported, along with the results of a previous experimental campai n carried out on th sam topic. Full-scale ext rnal beam-c lumn j int specimens are tested, with and without strengthening, an wi h differ nt characteristics in terms of amount of beam lo gitudinal reinforcement and concrete compressive . Different failure modes are observed for the as-built specim ns (j int failure w th ut (J) or after (BJ) bea fl xural yi lding). The effectiven ss f the adopted strengthening approach is d monstra ed, observing an increase in joint shear strength and subassemblag ductility and – unless a joint failure in compress on occur – a possible modification of the failure mode i to a ductile, flexure-controlled response of the subassemblage, as for code-c mpliant beam-colu n jo nts. © 2022 The Auth rs. 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 u der re ponsibility of scientific committe of the XIX ANIDIS C nfere ce, Seismic Engineering in Italy Keywords: existing buildings; seismic loading; reinforced concrete; beam-column joints; strengtheni g; experi ental results XIX ANIDIS Conference, Seismic Engineering in Italy Experimental Analysis of the Effectiveness of Pre-Stressed Steel Strips for the Strengthening of Beam-Column Joints in Existing RC Buildings Maria Teresa De Risi a *, Paolo Ricci a , Gerardo Mario Verderame a a University of Naples Federico II, via Claudio 21, 80125, Naples, Italy

* Corresponding author. Tel.: +39-081-7683490 E-mail address: mariateresa.derisi@unina.it * Corresponding author. Tel.: +39-081-7683490 E-mail address: mariater sa.derisi@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 © 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.2023.01.125