• Structural Engineering and Mechanics
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• 제91권4호
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• pp.335-347
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• 2024

This paper presents the behavior of geopolymer concrete beams reinforced with glass fiber reinforced polymer (GFRP) bars. In the study, ordinary Portland cement concrete and geopolymer concrete beams having GFRP bars were prepared and tested under four-point loading. The load-deflection diagrams and load capacities of the tested beams were obtained. It was observed that the tested beams exhibited good ductility and significant deflection capacity. The results showed that increasing the tension GFRP reinforcement ratio caused enhancement in the strength capacity of geopolymer concrete beams. In addition, the tested beams were analyzed to obtain the load capacity and the load-deflection responses. The theoretical load-deflection curves and load bearing capacities have been predicted well with the test results. Parametric study has been performed to determine the influences of concrete strength, shear span to depth ratio (a/d) and reinforcement ratio on the behavior of geopolymer concrete beams longitudinally reinforced with GFRP bars. It was concluded that increasing concrete strength led to an increase in load capacity. Besides, the ultimate load increased as the reinforcement ratio increased. On the other hand, increasing a/d ratio reduced the ultimate load value of GFRP reinforced geopolymer concrete beams.

• Computers and Concrete
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• 제15권3호
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• pp.437-459
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• 2015

An experimental investigation on the behaviour of geopolymer composite concrete beams reinforced with conventional steel bars and various types of fibres namely steel, polypropylene and glass in different volume fractions under flexural loading is presented in this paper. The cross sectional dimensions and the span of the beams were same for all the beams. The first crack load, ultimate load and the loaddeflection response at various stages of loading were evaluated experimentally. The details of the finite element analysis using "ANSYS 10.0" program to predict the load-deflection behavior of geopolymer composite reinforced concrete beams on significant stages of loading are also presented. Nonlinear finite element analysis has been performed and a comparison between the results obtained from finite element analysis (FEA) and experiments were made. Analytical results obtained using ANSYS were also compared with the calculations based on theory and presented.

• Advances in concrete construction
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• 제8권1호
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• pp.33-37
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• 2019

The present investigation is mainly focused on studying the flexural behavior of reinforced geopolymer concrete (RGPC) beams under pure bending. In this study, copper slag (CS) was used as a partial replacement of fine aggregate. Sand and CS were blended in different proportions (100:0, 80:20, 60:40 and 40:60) (sand:CS) by weight. Fly ash and ground granulated blast furnace slag (GGBS) were used as binders and combination of sodium hydroxide (8M) and sodium silicate solution were used for activating the binders. The reinforcement of RGPC beam was designed as per guidelines given in the IS 456-2000 and tested under pure bending (two-point loading) after 28 days of ambient curing. After conducting two point load test the flexural parameters viz., moment carrying capacity, ultimate load, service load, cracking moment, cracking load, crack pattern and ultimate deflection were studied. From the results, it is concluded that RGPC beams have shown better performance up to 60% of CS replacement.

• Computers and Concrete
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• 제21권2호
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• pp.157-166
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• 2018

This article presents the flexural behaviour of reinforced fly ash (FA)-based geopolymer concrete (GPC) beams with partial replacement of FA for about 10% by weight with paper sludge ash (PSA). The beams were made of M35 grade concrete and cured under three curing conditions for comparison viz., ambient curing, external exposure curing, and oven curing at $60^{\circ}C$. The beams were experimentally tested at the 28th day of casting after curing by conducting two-point loading flexural test. Performance aspects such as load carrying capacity, first crack load, load-deflection and moment-curvature behaviours of both types of beams were experimentally studied and their results were compared under different curing conditions. To verify the response of reinforced GPC beams numerically, an ANSYS 13.0 finite element program was also used. The result shows that there is a good agreement between computer model failure behaviour with the experimental failure behaviour.

• Structural Engineering and Mechanics
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• 제31권5호
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• pp.567-585
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• 2009

The aim of this study was to investigate the flexural behavior of reinforced concrete beams strengthened with a novel strengthening system. Concrete beams were strengthened with a hybrid retrofit system consisting of high strength steel cords impregnated in an inorganic fireproof matrix (Geopolymer). The strengthened reinforced concrete beams along with non-strengthened control beams were tested monotonically under four point bending loading conditions. Moreover, an analytical model is introduced, that can be used to analyze the flexural performance of the strengthened beams. The experimental results indicate that the failure of the strengthened beams was based on the yielding of the reinforcement in the tension face of the beams, followed by a local slippage of the steel cords. The flexural stiffness of the strengthened beams was significantly improved compared to the stiffness of the non-strengthened beams. In conclusion, the strengthening system can provide an effective alternative to commercially available systems.