PSI - Issue 47

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 47 (2023) 654–659

© 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 IGF27 chairpersons Experimental data on reduction of GFRP strength reduction are obtained for various reinforcement schemes, maximum stresses in cycle and temperatures. Data is processed using proposed model. Transition to critical states points are defined. High descriptive capability of the model and its applicability under various loading conditions are demonstrated. Rationality and expediency of proposed model usage in composite structures design is concluded. © 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 IGF27 chairpersons Keywords: Composite; Damage accumulation; Mechanical properties degradation. 1. Introduction Ensuring the strength, reliability and safety of composite structures, which operate under cyclic loading, requires an accurate strength analysis. Its important aspect is degradation of the material mechanical properties associated with the fatigue damage accumulation. A number of experimental studies was carried out (Carraro and Quaresimin (2018), Philippidis and Passipoularidis (2007), van Paepegem and Degrieck (2002)). However, it is necessary to develop mathematical models that reflect the change in properties as cyclic exposure and take into account the influence of various loading conditions. Abstract This work is devoted to the problem of mathematical description of fatigue damage accumulation regularities and composites mechanical properties reduction under various loading conditions. Based on cumulative distribution functions using, the model of fatigue sensitivity curves description was earlier developed by authors. Main advantages of this model are usage of only two parameters and possibility of damage accumulation stages boundaries calculation. Experimental data on reduction of GFRP strength reduction are obtained for various reinforcement schemes, maximum stresses in cycle and temperatures. Data is processed using proposed model. Transition to critical states points are defined. High descriptive capability of the model and its applicability under various loading conditions are demonstrated. Rationality and expediency of proposed model usage in composite structures design is concluded. © 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 IGF27 chairpersons Keywords: Composite; Damage accumulation; Mechanical properties degradation. 1. Introduction Ensuring the strength, reliability and safety of composite structures, which operate under cyclic loading, requires an accurate strength analysis. Its important aspect is degradation of the material mechanical properties associated with the fatigue damage accumulation. A number of experimental studies was carried out (Carraro and Quaresimin (2018), Philippidis and Passipoularidis (2007), van Paepegem and Degrieck (2002)). However, it is necessary to develop mathematical models that reflect the change in properties as cyclic exposure and take into account the influence of various loading conditions. 27th International Conference on Fracture and Structural Integrity (IGF27) Influence of loading conditions on GFRP fatigue sensitivity curves parameters and transition to critical states Artur Mugatarov*, Oleg Staroverov, Valeriy Wildemann Center of Experimental Mechanics, Perm National Research Polytechnic University, 29, Komsomolsky prospect, Perm, 614990, Russia Abstract This work is devoted to the problem of mathematical description of fatigue damage accumulation regularities and composites mechanical properties reduction under various loading conditions. Based on cumulative distribution functions using, the model of fatigue sensitivity curves description was earlier developed by authors. Main advantages of this model are usage of only two parameters and possibility of damage accumulation stages boundaries calculation. 27th International Conference on Fracture and Structural Integrity (IGF27) Influence of loading conditions on GFRP fatigue sensitivity curves parameters and transition to critical states Artur Mugatarov*, Oleg Staroverov, Valeriy Wildemann Center of Experimental Mechanics, Perm National Research Polytechnic University, 29, Komsomolsky prospect, Perm, 614990, Russia

-* Corresponding author. E-mail address: cem_mugatarov@mail.ru -* Corresponding author. E-mail address: cem_mugatarov@mail.ru

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 IGF27 chairpersons 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 IGF27 chairpersons

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 IGF27 chairpersons 10.1016/j.prostr.2023.07.056