Fatigue analysis of unidirectional GFRP composites under combined bending and torsional loads

El-Assal, Ahmed; Khashaba, U.A.

doi:10.1016/j.compstruct.2006.02.026

Cited by 42 publications

(11 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Notoriously, fatigue failure occurs due to the application of fluctuating stresses that are lower than the stress needed to produce failure during a monotonous loading application. The study reported in [13] considered the fatigue effects in bonded regions of FRP plates used for small bridge applications, but only few information are found in terms of residual strength of the fibers [14][15][16] and FRP-reinforced elements [17,18]. In these studies the fatigue effects caused a reduction of the static strength as expected.…”

Section: Introduction and Research Significancementioning

confidence: 64%

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

et al. 2017

View full text Add to dashboard Cite

Abstract:In recent years, even if Fiber Reinforced Polymer (FRP) composites have been widely used for strengthening of civil buildings, a new generation of materials has been studied and proposed for historical masonry construction. These buildings, mainly made of stone work, are common in many areas of Europe and Asia and recent earthquakes has been the cause of many catastrophic failures. The brittleness of unreinforced historic masonry can be considerably reduced using new retrofitting lighter-weight materials such FRP, even if limitations were evidenced due to material and mechanical compatibility with poor substrates. Thus, fibrous reinforcements were used as long fibres incorporated into a cement or lime matrix, which better match with the properties of ancient masonry. The use of low strength fibers such as glass and basalt, respect to carbon, in presence of an alkaline matrix brought out durability issues, due to the chemical vulnerability of common glass and basalt fibres. The objective of this research is to explore the effects of selected aqueous environments and fatigue loading on the mechanical and physical properties of composite grids, made of E-CR (Electrical/Chemical Resistance) glass fibers and epoxy-vinylester resin, used as tensile reinforcement in new composite reinforced mortar systems. Glass-fiber-reinforced polymer (GFRP) coupons were subjected to tensile testing and a severe protocol of durability tests, including alkaline environment and fatigue tensile loads. Accelerated ageing tests were used to simulate long-term degradation in terms of chemical attack and consequent reduction of tensile strength. The ageing protocol consisted of immersion at 40 • C in alkaline bath made by deionized water and Ca(OH) 2 , 0.16% in weight, solution for 30 days. GFRP specimens aged and unaged were also tested under tensile fatigue cycles up to 1,000,000 cycles and a nominal frequency of 7.5 Hz. After this severe conditioning the tests indicate a good tensile strength retention of the GFRP in absence of fatigue loads, while a significant loss in fatigue life was experienced when both alkaline exposure and fatigue loads were applied.

show abstract

Section: Introduction and Research Significancementioning

confidence: 64%

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

et al. 2017

View full text Add to dashboard Cite

show abstract

“…There are several ways of inducing a state of in-plane shear [1,2] in a composite to model the shear stress-strain relationship. Examples are the Iosipescu test [1,[3][4][5], the 108 off-axis test [4][5][6][7], the [þ458/-458] ns tensile test [6,8,9,[10][11][12], the two-and three-rail shear test [13][14][15][16], torsion of a rod [17] and torsion of thin-walled tubes [18][19][20][21].…”

Section: Introductionmentioning

confidence: 99%

Modelling the nonlinear shear stress–strain behavior of a carbon fabric reinforced polyphenylene sulphide from rail shear and [(45°,−45°)]_4s tensile test

2008

View full text Add to dashboard Cite

In this article, the nonlinear shear stress-strain relationship of a carbon fabric-reinforced polyphenylene sulphide is investigated by performing and comparing both the [þ458/2458] ns tensile test and the three-rail shear test. First, quasi-static and hysteresis tests are performed to obtain the data necessary for the material model. Then, the material constants are optimized by comparing finite element simulations with the data derived from the experiments. The conducted experiments are simulated and the results are compared with the experiments, with excellent correspondence.

show abstract

“…If one wants to study the in‐plane shear behaviour of a composite, a large number of different experimental setups are available 1,2 . Typical examples are the [+45°/−45°] ns tensile test, 3–8 the 10° off‐axis test, 8–11 the Iosipescu test, 1,9,10,12 the two‐ and three‐rail shear test, 13–16 torsion of a rod 17 and torsion of thin‐walled tubes 18–21 …”

Section: Introductionmentioning

confidence: 99%

“…If fatigue loading conditions are required, then the rail shear test is only rarely considered 16 . The favourite test setup remains the torsion of thin‐walled tubes, despite its disadvantages, and it is sometimes combined with tension or bending in biaxial fatigue 18–21 . The [+45°/–45°] ns test is also used 3 for fatigue research.…”

Section: Introductionmentioning

confidence: 99%

Comparison of the modified three‐rail shear test and the [(+45°,−45°)]_ns tensile test for pure shear fatigue loading of carbon fabric thermoplastics

Baere

Paepegem

Degrieck

2008

Fatigue Fract Eng Mat Struct

View full text Add to dashboard Cite

A B S T R A C T The (three)-rail shear test is rarely considered for testing of fibre-reinforced composites under pure shear fatigue loading conditions because of all experimental difficulties. However, in this article, a carbon fabric-reinforced PPS is tested using a modified three-rail shear test setup. The results are compared with [(+45 • ,−45 • )] 4s tensile tests with good correspondence. All fatigue experiments were done with R = 0 and the influence of maximum shear stress and frequency is investigated. It can be concluded that an increase in maximum shear stress decreases fatigue lifetime, whereas an increase in frequency increases the lifetime. Before failure, a sudden increase in both temperature and permanent deformation could be detected. Creep tests yielded that the occurring deformation is mainly due to the fatigue loading, rather than due to creep phenomena. E 11 Stiffness of the composite in the warp (0 • ) direction E 22 Stiffness of the composite in the weft (90 • ) direction F Measured force obtained from the tensile machine G 12 Shear stiffness of the composite h Height of the three-rail shear specimen S T Ultimate shear strength of the composite t Thickness of the specimen (both [(+45 • ,−45 • )] 4s tensile as three-rail shear specimen) w width of the [(+45 • ,−45 • )] 4s tensile specimen X T Ultimate tensile strength of the composite Y T Ultimate compressive strength of the composite ε i Strain obtained from strain gauge i in the three-rail shear test ε xx Longitudinal strain in the [(+45 • ,−45 • )] 4s tensile test ε yy Transverse strain in the [(+45 • ,−45 • )] 4s tensile test ε 11 ult Ultimate strain in the warp (0 • ) direction ε 22 ult Ultimate strain in the weft (90 • ) direction γ 12 Shear strain ν 12 Poisson's ratio of the composite τ 12 Shear stress I N T R O D U C T I O N If one wantsto study the in-plane shear behaviour of a composite, a large number of different experimental setups are available. 1,2 Typical examples are the Correspondence: I. De Baere. E-mail: Ives.DeBaere@UGent.be [+45 • /−45 • ] ns tensile test, 3-8 the 10 • off-axis test, 8-11the Iosipescu test, 1,9,10,12 the two-and three-rail shear test, 13-16 torsion of a rod 17 and torsion of thin-walled tubes. [18][19][20][21] From all these tests mentioned above, the most universal method used for the determination of both in-plane shear modulus and shear strength is torsion of a thin-walled 414

show abstract

Fatigue analysis of unidirectional GFRP composites under combined bending and torsional loads

Cited by 42 publications

References 11 publications

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

Modelling the nonlinear shear stress–strain behavior of a carbon fabric reinforced polyphenylene sulphide from rail shear and [(45°,−45°)]_4s tensile test

Comparison of the modified three‐rail shear test and the [(+45°,−45°)]_ns tensile test for pure shear fatigue loading of carbon fabric thermoplastics

Contact Info

Product

Resources

About

Fatigue analysis of unidirectional GFRP composites under combined bending and torsional loads

Cited by 42 publications

References 11 publications

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

Properties of Aged GFRP Reinforcement Grids Related to Fatigue Life and Alkaline Environment

Modelling the nonlinear shear stress–strain behavior of a carbon fabric reinforced polyphenylene sulphide from rail shear and [(45°,−45°)]4s tensile test

Comparison of the modified three‐rail shear test and the [(+45°,−45°)]ns tensile test for pure shear fatigue loading of carbon fabric thermoplastics

Contact Info

Product

Resources

About

Modelling the nonlinear shear stress–strain behavior of a carbon fabric reinforced polyphenylene sulphide from rail shear and [(45°,−45°)]_4s tensile test

Comparison of the modified three‐rail shear test and the [(+45°,−45°)]_ns tensile test for pure shear fatigue loading of carbon fabric thermoplastics