PSI - Issue 64

ScienceDirect Structural Integrity Procedia 00 (2023) 000–000 Structural Integrity Procedia 00 (2023) 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 64 (2024) 2051–2058

SMAR 2024 – 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures Practical Applications of Fe-SMA for Punching Shear Strengthening of RC Slabs SMAR 2024 – 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures Practical Applications of Fe-SMA for Punching Shear Strengthening of RC Slabs

Ravina Sriram a* , Roland Bärtschi a , Yunus Harmanci b a Baertschi Partner Bauingenieure AG, Landstrasse 28, 5420 Ehrendingen, Switzerland b Empa, Überlandstrasse 129, 8600 Dübendorf, Switzerland Ravina Sriram a* , Roland Bärtschi a , Yunus Harmanci b a Baertschi Partner Bauingenieure AG, Landstrasse 28, 5420 Ehrendingen, Switzerland b Empa, Überlandstrasse 129, 8600 Dübendorf, Switzerland

Abstract Punching shear failure causes a sudden and brittle collapse in column-supported reinforced concrete slabs, which can occur due to increased loading, design and construction deficiencies, or long-term degradation of the structural system. Recently introduced innovative materials aim to improve strengthening methods, minimizing disruptions for building owners. Among these materials, iron-based shape memory alloys (Fe-SMA) show promise for effectively reinforcing and prestressing existing concrete structures. Based on the authors' experience in structural assessment and strengthening of existing buildings and parking garages, two specific applications are presented: strengthening with Fe-SMA bars in the hogging moment region to enhance the slab's bending resistance above the column, and in the sagging bending region to transfer moments while preventing plastic moment redistribution. Both case studies include punching shear calculations following Level III/IV approximations according to fib model code. This paper highlights the practical and effective use of iron-based shape memory alloys in addressing punching shear deficiencies in existing concrete slabs, offering a valuable solution to enhance the safety and performance of RC structures. © 2024 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 SMAR 2024 Organizers Keywords: Iron-based shape memory alloy; punching shear; structural strengthening; practical application; condition assessment Abstract Punching shear failure causes a sudden and brittle collapse in column-supported reinforced concrete slabs, which can occur due to increased loading, design and construction deficiencies, or long-term degradation of the structural system. Recently introduced innovative materials aim to improve strengthening methods, minimizing disruptions for building owners. Among these materials, iron-based shape memory alloys (Fe-SMA) show promise for effectively reinforcing and prestressing existing concrete structures. Based on the authors' experience in structural assessment and strengthening of existing buildings and parking garages, two specific applications are presented: strengthening with Fe-SMA bars in the hogging moment region to enhance the slab's bending resistance above the column, and in the sagging bending region to transfer moments while preventing plastic moment redistribution. Both case studies include punching shear calculations following Level III/IV approximations according to fib model code. This paper highlights the practical and effective use of iron-based shape memory alloys in addressing punching shear deficiencies in existing concrete slabs, offering a valuable solution to enhance the safety and performance of RC structures. © 2024 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 SMAR 2024 Organizers Keywords: Iron-based shape memory alloy; punching shear; structural strengthening; practical application; condition assessment © 2024 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 SMAR 2024 Organizers

* Corresponding author. Tel.: +41 56 204 47 70. E-mail address: ravina.sriram@baertschipartner.ch * Corresponding author. Tel.: +41 56 204 47 70. E-mail address: ravina.sriram@baertschipartner.ch

2452-3216 © 2024 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 SMAR 2024 Organizers 2452-3216 © 2024 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 SMAR 2024 Organizers

2452-3216 © 2024 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 SMAR 2024 Organizers 10.1016/j.prostr.2024.09.296