Shear Performance of Reinforced Concrete Beams with GFRP

2020 ◽  
Vol 1002 ◽  
pp. 531-540
Author(s):  
Suaad K. Ibraheem Al-Fadhli

"Fiber Reinforced Polymers FRP" provide good alternatives to regular reinforcing steel, as their resistance to environmental factors specifies them and provide durability, in addition to their appropriate prices. These polymers are of various compositions and forms, some of which have a basic composition of glass fibers, others contain carbon or additional materials. They have used instead of steel reinforcement as the main longitudinal rebar, also as laminates that can be attached to the concrete surfaces for shear or flexural resistance. In this study, "Glass Fiber Reinforced Polymers GFRP" has tested for shear performance, where a practical program has applied. Three "simply supported beams" as control specimens have been prepared and tested, with the other nine beams with different combinations of reinforcement of steel and GFRP for flexure and shear resistance. Specimens have examined and the results have analyzed. The results showed that the use of GFRP as for main reinforcement with GFRP laminates instead of shear steel reinforcement increases the load capacity by 11%, also decreases the deflection by 46%.

2019 ◽  
Vol 9 (14) ◽  
pp. 2838 ◽  
Author(s):  
Sayed Mohamad Soleimani ◽  
Sajjad Sayyar Roudsari

During dynamic events (such as impact forces), structures fail to absorb the incoming energy and catastrophic collapse may occur. Impact and quasi-static tests were carried out on reinforced concrete beams with and without externally bounded sprayed and fabric glass fiber-reinforced polymers. For impact loading, a fully instrumented drop-weight impact machine with a capacity of 14.5 kJ was used. The drop height and loading rate were varied. The load-carrying capacity of reinforced concrete beams under impact loading was obtained using instrumented anvil supports (by summing the support reactions). In quasi-static loading conditions, the beams were tested in three-point loading using a Baldwin Universal Testing Machine. ABAQUS FEA software was used to model some of the tested reinforced concrete beams. It was shown that the stiffness of reinforced concrete beams decreases with increasing drop height. It was also shown that applying sprayed glass fiber-reinforced polymers (with and without mechanical stiffeners) and fabric glass fiber-reinforced polymers on the surface of reinforced concrete beams increased the stiffness. Results obtained from the software analyses were in good agreement with the laboratory test results.


Materials ◽  
2020 ◽  
Vol 13 (16) ◽  
pp. 3545
Author(s):  
Alessia Romani ◽  
Andrea Mantelli ◽  
Raffaella Suriano ◽  
Marinella Levi ◽  
Stefano Turri

Despite the large use of composites for industrial applications, their end-of-life management is still an open issue for manufacturing, especially in the wind energy sector. Additive manufacturing technology has been emerging as a solution, enhancing circular economy models, and using recycled composites for glass fiber-reinforced polymers is spreading as a new additive manufacturing trend. Nevertheless, their mechanical properties are still not comparable to pristine materials. The purpose of this paper is to examine the additive re-manufacturing of end-of-life glass fiber composites with mechanical performances that are comparable to virgin glass fiber-reinforced materials. Through a systematic characterization of the recyclate, requirements of the filler for the liquid deposition modeling process were identified. Printability and material surface quality of different formulations were analyzed using a low-cost modified 3D printer. Two hypothetical design concepts were also manufactured to validate the field of application. Furthermore, an understanding of the mechanical behavior was accomplished by means of tensile tests, and the results were compared with a benchmark formulation with virgin glass fibers. Mechanically recycled glass fibers show the capability to substitute pristine fillers, unlocking their use for new fields of application.


2020 ◽  
Vol 9 (2) ◽  
pp. 350
Author(s):  
Louay A. Aboul-Nour ◽  
Ragab S. Mahmoud ◽  
Mahmoud A. Khater ◽  
Nesma M. Moselhy

The major cause of concrete structures deterioration is steel corrosion. Consequently, this situation has led researchers to study and test other reinforcement alternatives that are noncorrosive in nature. Rapidly emerging developments in the field of material technology has led to the development of fiber reinforced polymers (FRP). This research focuses on the flexural behavior of carbon, glass, aramid, and basalt (CFRP, GFRP, AFRP, and BFRP) fiber reinforced polymers bars as alternatives to the traditional steel reinforcement in concrete. The study involves a nonlinear numerical finite element analysis of a simply supported reinforced concrete beams subjected to cyclic loading, where the ANSYS program is utilized. The numerical model verification is executed on the experimental beams for ensuring the efficiency of ma-terial models, cyclic loading and various elements. Hysteresis curves are produced for each beam and analyzed, where loads, deflections, and cracks propagation are inspected and discussed. The results reveal that, the full replacement of traditional steel bars with CFRP bars gives the greatest increase in the ultimate load capacity by 38.5%. Also, other results are summarized in this paper. 


2019 ◽  
Vol 56 (3) ◽  
pp. 616-620
Author(s):  
Virgil Florescu ◽  
Dorin Rus ◽  
Laurentiu Rece

The thermoplastic materials studied are biphasic. They consist of a polymer mass and a short glass fiber, the percentage being between 10 and 30%. We have shown, both analytically and graphically, the evolution of wear occurring on the steel surface in contact with glass fiber-reinforced polymers. The evolution in time of this process depends on the evolution of the friction coefficient in the process of the dry linear contact between different polymers and different types of steels. We have made a connection between the theoretical case and the experimental results. The experimental method used was the wear imprint method through which the wear depth and wear volume were determined. The wear process is complex and is accompanied by adhesion and corrosion phenomena. Any modification of the input parameters such as speed, temperature, load, quantity of glass fibers in the polymer lead at a certain one evolution of the wear behaviour of the composite material.


2017 ◽  
Vol 747 ◽  
pp. 525-532 ◽  
Author(s):  
Lara Calabrese ◽  
Francesco Micelli ◽  
Marco Corradi ◽  
Maria Antonietta Aiello ◽  
Antonio Borri

Many areas of Europe, especially Italy, Greece, Slovenia and other Balkan States, are generally associated with earthquakes. In the last two decades Fiber Reinforced Polymers (FRP) have gained an increasing interest, mostly for upgrading, retrofitting and repair of masonry and timber structures belonging to the architectural heritage. Recent researches demonstrated that masonry constructions or single structural elements are likely to be effectively repaired or enhanced in their mechanical properties using FRPs. The objective of the research presented in this paper is to study the long-term behavior of composite grids, made of E-CR glass fibers and epoxy-vinylester resin, subjected to harsh environmental factors including fatigue loading and ageing in aqueous solution. The paper presents new original test results on the relationship between the durability and the governing material properties of GFRP (Glass Fiber Reinforced Polymers) grids in terms of tensile strength and axial strains, using specimens cut off from GFRP grids before and after ageing in aqueous solution. The tensile strength of a GFRP grid was measured after conditioning in alkaline bath made by deionized water and Ca(OH)2, 0.16% in weight, solution. The reduction in terms of tensile strength and Young’s modulus of elasticity compared to unconditioned specimens is illustrated and discussed. This degradation indicated that extended service in alkaline environment under fatigue loads may produce reductions in the GFRP mechanical properties which should be considered in design, where cyclic loads and aggressive conditions are prevented in service life.


2017 ◽  
Vol 165 ◽  
pp. 65-73 ◽  
Author(s):  
Davi M. Montenegro ◽  
Francesco Bernasconi ◽  
Markus Zogg ◽  
Matthias Gössi ◽  
Rafael Libanori ◽  
...  

2013 ◽  
Vol 3 (3) ◽  
pp. 161-176
Author(s):  
D. H. Perelles ◽  
M. F. Medeiros ◽  
M. R. Garcez

RESUMOO reforço de estruturas com Polímeros Reforçados com Fibras (PRF) é uma alternativa que tem sido muito utilizada em intervenções executadas em elementos de concreto armado. A fibra de carbono é a mais empregada na formação dos compósitos de reforço utilizados em obras civis. Existe, no entanto, a possibilidade de se ampliar as opções de fibras formadoras do compósito utilizando as fibras de aramida e de vidro. Como uma ferramenta alternativa de tomada de decisão, o Método de Análise Hierárquica, baseado em critérios analisados de forma qualitativa e quantitativa, será utilizado neste trabalho para a avaliação das fibras de carbono, aramida e vidro, de forma a se obter qual material seria o mais apropriado para a execução de um reforço estrutural considerando como principais parâmetros de análise os custos dos materiais e as tensões e as deformações que os elementos poderão apresentar. A aplicação desta técnica de interpretação de resultados se mostrou muito útil, podendo ser considerada adequada para estudos que exijam uma tomada de decisão entre diferentes sistemas de reforço com PRF.Palabras clave: Reforço estrutural; polímeros reforçados com fibras; carbono; aramida; vidro; método da análise hierárquica.ABSTRACTStrengthening structures with Fiber Reinforced Polymers (FRP) is an alternative that has been used in interventions performed on reinforced concrete elements. Carbon fibers are the most used in the formation of composite reinforcement used in civil works. There is, however, possible to expand the options of forming fibers using the composite fibers of aramid and glass. As an alternative decision-making tool, the Analytic Hierarchy Process, based on criteria analyzed qualitatively and quantitatively, will be used in this work for the evaluation of carbon, aramid and glass fibers in order to obtain what material would be more suitable for the implementation of a structural reinforcement considering how key parameters of analysis material costs and the tensions and strains that may exhibit elements. This decision-making tool showed useful and can be considered suitable to select different FRP systems.Keywords: Structural strengthening; fiber-reinforced polymers; carbon; aramid; glass; hierarchical analysis method.


2014 ◽  
Vol 900 ◽  
pp. 449-454
Author(s):  
Giosuè Boscato

The present work proposes and analyses the solution for seismic behaviour of GFRP (Glass Fiber Reinforced Polymers) applications to evaluate the performances respect to dynamic actions considering the global effect on historical structures. The good strength-self-weight relationship defines the GFRP pultruded profile as an efficacious and innovative solution for structural rehabilitation of historical buildings. The composite material with polymeric matrix, FRP (Fiber Reinforced Polymers), is widely used in civil engineering as sheets, bars and strips. Recently a new technology was adopted to improve the structural response with limited increment of dead load with reversible and independent solution.


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