PSI - Issue 64

First page Table of contents Previous page 1393 Next page Last page

Available online at www.sciencedirect.com Structural Integrity Procedia 00 (2023) 000 – 000 Available online at www.sciencedirect.com ^ĐŝĞŶĐĞ ŝƌĞĐƚ Structural Integrity Procedia 00 (2023) 000 – 000 ^ĐŝĞŶĐĞ ŝƌĞĐƚ

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 64 (2024) 1279–1286

SMAR 2024 – 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures Measuring Strain and Crack Evolution in Reinforced Concrete under Monotonic and Fatigue Tension using Fiber Optic Sensors SMAR 2024 – 7th International Conference on Smart Monitoring, Assessment and Rehabilitation of Civil Structures Measuring Strain and Crack Evolution in Reinforced Concrete under Monotonic and Fatigue Tension using Fiber Optic Sensors Abstract For reliable service life prediction of reinforced concrete (RC) structures, a fundamental knowledge of the damage development under repeated subcritical loading is essential. Assessment of remaining service life is in practice mostly based on elaborate visual inspection of the concrete surface. To overcome this time-consuming process, it is crucial to consider continuously gained information on the damage state of the existing structure by comprehensive strain measurement. Based on this premise, the authors have developed a monitoring concept that involves the external application of two dimensionally arranged distributed fiber optic sensors (FOS) for high-resolution strain measurement. This paper presents the first preliminary studies validating this general concept and shows how strain and crack development under monotonic and stepwise increasing fatigue tensile loading can be accurately monitored. The results clearly demonstrate that crack initiation can be predicted based on strain measurements long before the actual crack formation and that even after crack initiation, the gradual crack opening can be reliably monitored. Furthermore, several hundred cycles (before and after crack formation) have no impact on measurement quality. © 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 Abstract For reliable service life prediction of reinforced concrete (RC) structures, a fundamental knowledge of the damage development under repeated subcritical loading is essential. Assessment of remaining service life is in practice mostly based on elaborate visual inspection of the concrete surface. To overcome this time-consuming process, it is crucial to consider continuously gained information on the damage state of the existing structure by comprehensive strain measurement. Based on this premise, the authors have developed a monitoring concept that involves the external application of two dimensionally arranged distributed fiber optic sensors (FOS) for high-resolution strain measurement. This paper presents the first preliminary studies validating this general concept and shows how strain and crack development under monotonic and stepwise increasing fatigue tensile loading can be accurately monitored. The results clearly demonstrate that crack initiation can be predicted based on strain measurements long before the actual crack formation and that even after crack initiation, the gradual crack opening can be reliably monitored. Furthermore, several hundred cycles (before and after crack formation) have no impact on measurement quality. © 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 © 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 Henrik Becks* a , Josef Hegger a , Martin Classen a a RWTH Aachen University, Mies-van-der-Rohe-Str. 1, 52074, Aachen, Germany Henrik Becks* a , Josef Hegger a , Martin Classen a a RWTH Aachen University, Mies-van-der-Rohe-Str. 1, 52074, Aachen, Germany

Keywords: Concrete; Fatigue; Tensile loading; Strain development; Crack detection; Fiber Optic Sensors (FOS)

* Corresponding author. Tel.: +49241 80 28053 E-mail address: hbecks@imb.rwth-aachen.de * Corresponding author. Tel.: +49241 80 28053 E-mail address: hbecks@imb.rwth-aachen.de

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

Made with FlippingBook Digital Proposal Maker