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Highlights • Tensile behaviour of different GFRP laminates under elevate temperatures has is investigated. • Laminates with continuous unidirectional fibers showed the best tensile performance. • Laminates with chopped strand fibers showed the weakest tensile performance. • Laminates with continuous woven fibers performed better than chopped strand and weaker than unidirectional laminates. Abstract This study was aimed at gaining an improved understanding of the behavior of glass fiber-reinforced polymer laminates at elevated temperatures by means of testing laminate specimens with unidirectional, woven, and randomly distributed (chopped strand mat) fibers. The testing parameters were temperature, the type of fiber, and the thickness of the laminates. The failure modes of the specimens and their elasticity moduli at ambient temperature were investigated, and analysis of variance was conducted to determine the contribution of each parameter to the behavioral test results. The findings showed that among the parameters, an increase in temperature exerted the strongest effect on the specimens. The unidirectional laminate specimens exhibited the best performance, maintaining nearly 40% of their loading capacity at 550 °C. At this temperature, the woven laminate specimens could not carry any tensile load, and at 400 °C, the laminate specimens containing randomly distributed fibers lost all their strength. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the flexural and impact behaviour of GFRP laminates after exposure to elevated temperatures. The effect of fibre's length and orientation, laminate's thickness, and exposure time is studied. A total number of 540 tests in terms of three-point bending and Charpy impact tests were conducted to obtain the mechanical properties. In addition, SEM analyses were carried out to investigate the degradation mechanisms. Finally, statistical study was conducted to investigate the contribution of each variable and develop probabilistic models using ANOVA and linear Bayesian regression method. The results showed that generally the flexural and impact properties of GFRP laminates decrease by increasing the temperature and time of exposure as well as decreasing the laminates' thickness. It is also observed that laminates with unidirectional fibres have the best performance under elevated temperatures, while laminates with randomly distributed fibres are the most vulnerable type. The performance of laminates with woven fibres are almost between those two other types. However, all types of the laminates lost almost all their flexural strength and impact energy absorption capacity at 300 °C. [ABSTRACT FROM AUTHOR]

This study investigates the tensile properties of various GFRP laminates after exposure to elevated temperatures. Fiber configuration, exposure temperature and laminate thickness were considered as the test variables. A total number of 180 specimens were tested in tension to obtain the mechanical properties of GFRP laminates. Alongside the mechanical tests, SEM analyses were conducted on selected samples before testing to investigate the resin, fiber, and their interface damages. Regardless of the sample type, it was generally observed that the reduction rate in the tensile strength increased with an increase in the exposure time and a decrease in the laminates' thickness. The results of tensile tests after exposure to elevated temperatures showed that the laminates with continuous unidirectional fibers performed the best, laminates with chopped strand randomly distributed fibers performed the worst, and the performance of the laminates with woven continuous fibers was somewhere in between. The maximum tensile strength reductions for the unidirectional and woven laminates were about 50% after exposure to 300 °C, whereas random chopped strand laminates lost almost all of their load carrying capacity under this exposure condition. [ABSTRACT FROM AUTHOR]