PSI - Issue 75

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia (2025) 000 – 000

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 75 (2025) 353–362

Fatigue Design 2025 (FatDes 2025) On the determination of fracture properties of specimens subjected

to periodic fatigue loadings using DIC J. Filho a *, L. Wittevrongel a , F. Pierron a , P. Lava a a MatchID NV, Leiekaai 25A, 9000 Gent, Belgium

© 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 the responsibility of Dr Fabien Lefebvre with at least 2 reviewers per paper Abstract In this work, some important concepts are covered in the context of measuring the fracture properties of specimens subjected to high frequency periodic fatigue loadings using Digital Image Correlation (DIC). For fatigue tests, depending on the selected cycle frequency, high-speed machine vision cameras are commonly employed. These cameras can be replaced by low-cost, high resolution and limited-frame-rate machine-vision cameras. A signal-locking approach can be used in these applications to grab images at the loading peaks or artificially reconstruct the source signal using aliasing. With regard to the fracture properties, the stress intensity factors, crack-tip position and strain energy release rate can be measured using DIC. Here a fully integrated system is presented and validated using the Williams’ series expansion model . © 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 the scientific committee of the Fatigue Design 2025 organizers Keywords: Digital image correlation; signal-locking; fatigue tests; fracture properties 1. Introduction Digital Image Correlation (DIC) is an optical-numerical technique capable of measuring the full-field displacements and deformations of a specimen subjected to any loading condition, including periodic loading (Sutton et al. (2009)). DIC can overcome several limitations faced by conventional techniques ( e.g. extensometers, strain gauges). For instance, it is not straightforward to position sensors in some specimens, mainly due to low adherence and large deformations, and these techniques can only measure local displacements or deformations. Full-field data obtained by

* Corresponding author. Tel.: +32 9 223 64 41. E-mail address: joao.filho@matchid.eu

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 the scientific committee of the Fatigue Design 2025 organizers

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 the responsibility of Dr Fabien Lefebvre with at least 2 reviewers per paper 10.1016/j.prostr.2025.11.036