PSI - Issue 83

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ScienceDirect

Procedia Structural Integrity 83 (2026) 154–161

© 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 the scientific committee of the ESIAM26 organizers Abstract Fiber-Reinforced Polymers (FRP) composite materials remain widely used as concrete reinforcement material due to the excellent strength-to-weight ratio, as well as the resistance to corrosion. However, the behavior of the material when it comes into contact with fire has continued to remain an important issue in relation to the safety of the structure. This report gives a summary of the current research activities in relation to the behavior after the fire in concrete structures reinforced with FRP composite materials. According to the research, FRP materials continue to show significant degradation concerning the strength, stiffness, as well as the adhesion properties between the concrete and the FRP materials when they come into contact with elevated temperatures. The glass transition temperature of the polymers, between 100 °C and 180 °C, continues to remain the most significant factor, beyond which the material can easily experience softening, decomposition, as well as the destruction of composite material properties. Additionally, the protective systems, concrete cover, as well as the external insulation, as a means of slowing down the process, continue to remain unable to halt the irreversible process concerning the destruction of the mechanical properties. The fourth European Conference on the Structural Integrity of Additively Manufactured Materials (ESIAM26) Post-Fire Residual Strength and Stiffness Degradation in FRP Reinforced Concrete Structures Wijdane Kachach a , Asad Hanif a,b,* a Civil and Environmental Engineering Department, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia b Interdisciplinary Research Center for Construction and Building Materials, King Fahd University of Petroleum & Minerals, Dhahran 31261, Saudi Arabia

Keywords: Fiber-reinforced polymers (FRP); Residual Strength; Thermal Degradation; Fire Performance; Post-Fire Behavior

* Corresponding author: E-mail address: asad.hanif@kfupm.edu.sa; ahanif@connect.ust.hk Tel.: +966-13-8603630

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 the scientific committee of the ESIAM26 organizers 10.1016/j.prostr.2026.07.018