Issue 77

A. Sivtseva et alii, Fracture and Structural Integrity, 77 (2026) 138-172; DOI: 10.3221/IGF-ESIS.77.10

Phenomenological models of residual mechanical properties of polymer composites under fatigue loading: review, analysis of descriptive ability and classification

Anastasia Sivtseva, Artur Mugatarov, Oleg Staroverov, Valeriy Wildemann Perm National Research Polytechnic University, Russia cem_sivtseva@mail.ru, https://orcid.org/0000-0002-4348-7491 cem_mugatarov@mail.ru, https://orcid.org/0000-0002-2229-8181 cem_staroverov@mail.ru, oastaroverov@pstu.ru, https://orcid.org/0000-0001-6095-0962 wildemann@pstu.ru, https://orcid.org/0000-0002-6240-4022

Citation: Sivtseva, A., Mugatarov, A., Staroverov, O., Wildemann, V., Phenomenological models of residual mechanical properties of polymer composites under fatigue loading: review, analysis of descriptive ability and classification, Fracture and Structural Integrity, 77 (2026) 138-172.

A BSTRACT . In this work, a review and mathematical analysis of phenomenological models of residual strength and residual stiffness of polymer composite materials under fatigue loading have been carried out. The methodology of the analysis is described in detail, including various approaches to determining damage based on changes in mechanical properties, as well as the requirements for functions that can be used to describe experimental dependencies. The considered models have been classified according to the characteristic form of their mathematical function: polynomial, power, exponential, logarithmic, and trigonometric models. A distinct category has been established for models utilizing cumulative distribution functions. The possibilities for further development and application of phenomenological models of residual mechanical properties for the improvement of strength analysis approaches for composite structures have been outlined. K EYWORDS . Polymer composites, Fatigue, Damage, Models of residual mechanical characteristics, Residual strength, Residual stiffness.

Received: 18.03.2026 Accepted: 20.04.2026 Published: 22.04.2026 Issue: 07.2026

Copyright: © 2026 This is an open access article under the terms of the CC-BY 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

I NTRODUCTION uring utilization, structures made of polymer composite materials are subjected to various types of external influences, including cyclic loads. Under this type of loading, gradual accumulation of fatigue damage occurs, manifested in matrix cracking, fiber-matrix debonding, formation and propagation of delaminations, local fiber D

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