PSI - Issue 75

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ScienceDirect

Procedia Structural Integrity 75 (2025) 709–718 Structural Integrity Procedia 00 (2025) 000–000 Structural Integrity Procedia 00 (2025) 000–000

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© 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 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the Fatigue Design 2025 organizers. Keywords: Fatemi-Socie criterion; multiaxial fatigue; frequency-domain fatigue analysis; power spectral density (PSD); critical plane approach; random vibration fatigue Abstract Multiaxial fatigue analysis is essential in mechanical engineering applications. This work introduces a frequency-domain adaptation of the Fatemi–Socie critical plane method, o ff ering a fast and accurate alternative for fatigue assessment under mutiaxial random loading. By reformulating key parameters using power spectral density functions and a new covariance-based plane search algo rithm, the method significantly reduces the computational e ff ort. A comparison with time-domain results shows strong agreement in fatigue life predictions, confirming the reliability and e ffi ciency of the proposed approach for analyzing complex, non-proportional multiaxial loading scenarios. © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the Fatigue Design 2025 organizers. Keywords: Fatemi-Socie criterion; multiaxial fatigue; frequency-domain fatigue analysis; power spectral density (PSD); critical plane approach; random vibration fatigue Fatigue Design 2025 (FatDes 2025) Fast and accurate frequency-domain formulation of the Fatemi–Socie critical plane method for multiaxial random loading SgammaM. a, ∗ , Niesłony A. b , Bo¨hmM. b , Chiocca A. a , Bucchi F. a , FrendoF. a a University of Pisa, Department of Civil and Industrial Engineering, Largo Lucio Lazzarino 2, 56123 Pisa, Italy b Opole University of Technology, Department of Mechanics and Machine Design, ul. Mikołajczyka 5, 45-271 Opole, Poland Abstract Multiaxial fatigue analysis is essential in mechanical engineering applications. This work introduces a frequency-domain adaptation of the Fatemi–Socie critical plane method, o ff ering a fast and accurate alternative for fatigue assessment under mutiaxial random loading. By reformulating key parameters using power spectral density functions and a new covariance-based plane search algo rithm, the method significantly reduces the computational e ff ort. A comparison with time-domain results shows strong agreement in fatigue life predictions, confirming the reliability and e ffi ciency of the proposed approach for analyzing complex, non-proportional multiaxial loading scenarios. Fatigue Design 2025 (FatDes 2025) Fast and accurate frequency-domain formulation of the Fatemi–Socie critical plane method for multiaxial random loading SgammaM. a, ∗ , Niesłony A. b , Bo¨hmM. b , Chiocca A. a , Bucchi F. a , FrendoF. a a University of Pisa, Department of Civil and Industrial Engineering, Largo Lucio Lazzarino 2, 56123 Pisa, Italy b Opole University of Technology, Department of Mechanics and Machine Design, ul. Mikołajczyka 5, 45-271 Opole, Poland Multiaxial fatigue assessment continues to represent a crucial challenge in contemporary structural engineering, especially for components subjected to complex and random loadings commonly found in aerospace, automotive, and general mechanical applications [21, 30, 41]. Such conditions typically involve multiaxial, non-proportional, and stochastic characteristics, complicating fatigue analysis due to the inherent variability and randomness of the applied loads [5, 2, 25]. Traditional fatigue life prediction methods, primarily conducted in the time domain, usually rely on detailed stress or strain histories combined with cycle-counting techniques such as the rainflow counting method, along with cumu lative damage models like Miner’s rule [32, 15, 22, 18]. Although widely validated and embedded into engineering standards, these approaches are computationally intensive under random and multiaxial loading conditions, making them challenging for practical engineering applications [6, 24, 7, 10]. Multiaxial fatigue assessment continues to represent a crucial challenge in contemporary structural engineering, especially for components subjected to complex and random loadings commonly found in aerospace, automotive, and general mechanical applications [21, 30, 41]. Such conditions typically involve multiaxial, non-proportional, and stochastic characteristics, complicating fatigue analysis due to the inherent variability and randomness of the applied loads [5, 2, 25]. Traditional fatigue life prediction methods, primarily conducted in the time domain, usually rely on detailed stress or strain histories combined with cycle-counting techniques such as the rainflow counting method, along with cumu lative damage models like Miner’s rule [32, 15, 22, 18]. Although widely validated and embedded into engineering standards, these approaches are computationally intensive under random and multiaxial loading conditions, making them challenging for practical engineering applications [6, 24, 7, 10]. 1. Introduction 1. Introduction

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.2025.11.071 ∗ Corresponding author E-mail addresses: michele.sgamma@cisup.unipi.it (Sgamma M.)., a.nieslony@po.edu.pl (Niesłony A.). 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the Fatigue Design 2025 organizers. ∗ Corresponding author E-mail addresses: michele.sgamma@cisup.unipi.it (Sgamma M.)., a.nieslony@po.edu.pl (Niesłony A.). 2210-7843 © 2025 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of the Fatigue Design 2025 organizers.