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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]

This paper presents the results of diagonal compression tests conducted on a series of un-reinforced and reinforced masonry specimens. Reinforced specimens were strengthened by using three types of mortar coating (with and without inner reinforcement), mesh reinforcement, and PP-band reinforcement. In particular, four different reinforcement methods with mortar coating (bare mortar coating, coating with steel mesh, coating with polymer reinforcement, and coating with GFRP mesh reinforcement), three different mesh-only reinforcement (steel mesh, polymer mesh with larger grids, and polymer mesh with smaller grids), and 2 different arrangements of PP-bands (4 × 4 and 6 × 6) were tested. Also, two different un-reinforced specimens (with and without mortar between bricks in a row) were tested to observe the effect of this matter. Each reinforcement method was tested with three wallettes and the effectiveness of each reinforcement method was observed in terms of both loading capability and ductility (especially the GFRP mesh reinforcement with mortar coating) because of the low resistance of the un-reinforced specimens. Shear stresses and strains and the elastic characteristics of each method are also presented in this paper. [ABSTRACT FROM AUTHOR]

• The effects of UV, moisture and elevated temperature on mechanical properties of GFRP pultruded profiles have been studied. • Different cross-sections were used to study the effect of profile type. • Effect of conditioning on different failure modes were investigated. • Regression models have been developed to predict the mechanical properties retentions. The present research examines the effects of UV radiation, moisture and elevated temperature on the mechanical properties of GFRP pultruded profiles. Flexural, compressive and tensile properties of different GFRP sections were studied after they were exposed for 1000, 1500, 2000 and 3000 h to UV radiation and water vapour condensation cycles. Mechanical tests, including three-point bending, compression and tension tests, SEM analyses, and statistical studies were conducted to gather comprehensive results. The results showed that the mechanical properties of various GFRP sections generally decreased with the duration of conditioning: however, the rate of the decrease that was only slight up to 1000 h, increased rapidly during 1000–2000 h, and again it was slow during 2000–3000 h. The maximum reductions were 34%, 28% and 23% after exposure to 3000 h cycles for bending, tensile and compression tests, respectively. In the bending tests, where inter-laminar shear failure controls ultimate strength, the degradation was greater compared to the situation where fibres fracture controls the failure. Further, regarding the cross-section parameter, it was concluded that the thickness and perimeter are the effective factors; the thinner the sample and the larger the perimeter, the greater is the reduction. However, the maximum effect of the cross section in terms of thickness and perimeter did not exceed 13% among all sections. [ABSTRACT FROM AUTHOR]

• Mechanical properties of various GFRP pultruded profiles under SWSSC is investigated. • Effect of initial exposure to UV radiation and moisture before subjecting to SWSSC is studied. • Samples initially exposed to UV and moisture show higher reductions after exposure to SWSSC. • Profiles with interlaminar shear failure are more vulnerable than profiles with bending failure. In this research, the mechanical properties of various glass fibre reinforced polymer (GFRP) pultruded profiles exposed to seawater sea sand concrete (SWSSC) and its combination with UV radiation and water vapour condensation were studied. The effect of different conditions, duration of conditioning, and the profile cross-section configuration on the mechanical properties were investigated. Three-point bending, tension, and compression tests were carried out to obtain the mechanical properties, including flexural, tensile and compressive strengths and tensile elastic modulus. Furthermore, in order to scrutiny the mechanisms and extent of damage, scanning electron microscopy (SEM) was carried out on the test samples before and after the exposures. Finally, regression models were derived according to the experimental data to describe the mechanical properties of profiles after exposure to the aggressive environments used in this study. The maximum reductions of about 30%, 33% and 46% were observed in three-point bending, tensile and compressive tests, respectively amongst all samples when exposed for 90 days to simulated SWSSC. These reductions increased for the same sections to 52%, 47%, and 50% when the GFRP profiles were pre-exposed for 3000 h to UV radiation and moisture before exposing for 90 days to simulated SWSSC. [ABSTRACT FROM AUTHOR]