PSI - Issue 72

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ScienceDirect

Procedia Structural Integrity 72 (2025) 164–171

12th Annual Conference of Society for Structural Integrity and Life (DIVK12) Asymmetrical environmental conditions influence on hygrothermal aging of polymer matrix composite laminates Mohamed Khodjet Kesba a , Billel Boukert a, *, Amina Benkhedda a , El Abbes Adda Bedia b a Aeronautical Sciences Laboratory, Aeronautics and space studies Institute, University of Blida 1, Algeria. b Material and Hydrology Laboratory, University of Sidi Bel Abbes, Algeria. Abstract Polymer matrix composites are increasingly employed in aircraft manufacturing, especially in military and aerospace sectors, with particular attention to their long-term resilience. When subjected to fluctuating temperatures and humidity levels, the lightweight and stiffness of composite materials become their primary advantages. Aerospace composite structures experience temperature and humidity variations during their operational lifespan, leading to a decrease in transition temperature due to heat exposure. This results in a significant stiffness reduction and the occurrence of hygrothermal deformations, caused by moisture absorption within the polymer matrix. Consequently, a notable decline in material strength is observed. Precisely assessing the internal stresses in composite structures under hygrothermal conditions is crucial for enhancing their durability and understanding environmental impacts. The classical laminated plate theory is employed to simulate the behavior of composite plates under asymmetric temperature and humidity conditions in both sides of the composite plate. Additionally, the Tsai model is integrated to account for mechanical performance degradation. Apart from temperature and humidity, other parameters such as reference values during the manufacturing process are considered in simulations. The findings indicate a significant influence of environmental factors on the behavior of composite plates, leading to the generation of residual stresses. Reference parameters and anisotropy (fiber orientation) are identified as factors contributing to the reduction of residual stresses. © 2026 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 Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia

Keywords: Asymmetric condition; Hygrothermal; Composite Aging; CLPT; Residual stress

* Corresponding author. Tel.: +213-771-285-129. E-mail address: boukert_bilel@univ-blida.dz

2452-3216 © 2026 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 Aleksandar Sedmak, Branislav Djordjevic, Simon Sedmak Dr. Simon Sedmak, ssedmak@mas.bg.ac.rs, Innovation Center of Faculty of Mechanical Engineering, Belgrade, Serbia 10.1016/j.prostr.2025.08.088