• Structural Engineering and Mechanics
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• v.90 no.1
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• pp.71-81
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• 2024

Fiber Reinforced Polymer (FRP) bars have now been widely adopted as an alternative to traditional steel reinforcements in infrastructure and civil industries worldwide due variety of merits. This paper presents a numerical methodology to investigate FRP bar-reinforced beam-column joint behavior under quasi-static loading. The proposed numerical model is validated with test results considering load-deflection behavior, damage pattern at beam-column joint, and strain variation in reinforcements, wherein the results are in agreement. The numerical model is subsequently employed for parametric investigation to enhance the end-span beam-column joint performance using different joint reinforcement systems. To reduce the manufacturing issue of bend in the FRP bar, the headed FRP bar is employed in a beam-column joint, and performance was investigated at different column axial loads. Headed bar-reinforced beam-column joints show better performance as compared to beam-column joints having an L-bar in terms of concrete damage, load-carrying capacity, and joint shear strength. The applicability and efficiency of FRP bars at different story heights have also been investigated with varying column axial loads.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.24 no.1
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• pp.23-31
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• 2011

This study carried out shear experiment for concrete deep beam reinforced FRP(Fiber Reinforced Polymers) bar to investigate shear strength of deep beam. The test conducted for 15 specimens, and the variables were shear span-to-depth ratio, reinforcement ratio, effective depth, reinforcement components of shear strength. crack, deflection are investigated based on shear experimental. We compared shear strength using ACI 318-08 STM with proposed equations that considered arching action according to shear span-to-depth ratio. Consequently shear strength of deep beam reinforced FRP bar presented higher shear strength than steel bar. ACI STM's predictions are better accurate than other predicting equations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.106-107
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• 2013

The purpose of this study is to characterize the bonding properties between reinforced bar and re-emulsion polymer cement mortar through the pull off test. The properties of polymer cement mortar before and after hardening were measured. Spiral reinforced steel bar was used to control the brittleness fracture of test specimens. In addition polymer content as experimental factors, the types of reinforced bar and corrosion were considered as well. Non linear FEM analysis was carried out to expect the behavior of bonding interface under the certain load.

• Composites Research
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• v.16 no.3
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• pp.32-40
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• 2003

In recent years, the investigation on the development of fiber reinforced plastic(FRP) Re-Bar has been greatly increased due to the attractive physical and mechanical properties of FRP. The primary reason of such a tendency is in the fact that it does not ordinarily cause durability problems such as those associated with steel reinforcement corrosion. This study is an experimental investigation on the flexural behavior of one-way concrete slabs, which can be used to construct bridge deck, reinforced with GFRP Re-Bar bundle. The tensile tests of GFRP Re-Bar produced by domestic industry and third point bending tests of one-way slab specimens reinforced with GFRP Re-Bar bundle are peformed. For all slab specimens, load-deflection relations are predicted by using the ACI committee 440 and the results are compared with experimental ones. In order to establish the design criteria or guidelines of concrete flexural member reinforced with FRP Re-Bar, it is needed to evaluate the serviceability limit state as well as the strength limit state.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.10a
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• pp.7-11
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• 2000

In this paper was studied on the mechanical characteristics of Glass Fiber Reinforced Plastics(GFRP) of the steel bar it is to replace. The advantage of FRP such as high strength, low weight and chemical inertness or noncorrosiveness can be fully exploited. GFRP bar were successfully fabricated at l0mm nominal diameters of solid and hollow types using a pultrusion method. Tensile and bending specimens from this bar were tested and compared with behavior of GFRP rebar and steel bar.

• KCI Concrete Journal
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• v.13 no.2
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• pp.67-74
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• 2001

In this study, a numerical model for the simulation of reinforced concrete columns subject to cyclic loading is presented. The model consists of three separate models representing concrete, reinforcing steel bars and bond-slip between a reinforcing bar and ambient concrete. The concrete model is represented by the plane stress plastic-damage model and quadrilateral finite elements. The nonlinear steel bar model embedded in truss elements is used for longitudinal and transverse reinforcing bars. Bond-slip mechanism between a reinforcing bar and ambient concrete is discretized using connection elements in which the hysteretic bond-slip link model defines the bond stress and slip displacement relation. The three models are connected in finite element mesh to represent a reinforced concrete structure. From the numerical simulation, it is shown that the proposed model effectively and realistically represents the overall cyclic behavior of a reinforced concrete column. The present plastic-damage concrete model is observed to work appropriately with the steel bar and bond-slip link models in representing the complicated localization behavior.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.276-279
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• 2005

FRP Composite materials are widely applicable in the construction industries as a load-bearing structural element or a reinforcing and/or repairing materials for the concrete. In this paper, we presented the flexural behavior of FRP Re-bar and steel reinforced concrete beams and only FRP re-bars reinforced concrete beams. FRP Re-bar manufactured by different fibers but the same vinylester resin. Also, surface of FRP Re-bars is coated garnet and glass fiber by epoxy to increase the adhesive to concrete. Experimental investigation pertaining to the load-deflection and load-strain characteristics of two classfied specimens is presented and the theoretical prediction is also conducted. In the investigation, the effects of FRP Re-bar reinforcement are estimated. The experimental results arc compared with theoretical predictions. Good agreements arc observed.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.177-180
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• 2008

Recently, the research of FRP bar as an alternative reinforcing material in reinforced concrete structures has increased to get an innovative solution to the corrosion problem. In addition to the noncorrosive nature of FRP materials, they also have a high strength-to-weight ratio. Therefore, when light weight concrete reinforced with FRP bar is used in marine environment, for instance floating structures, some advantages can be expected. But researches for the light weight concrete structure using FRP bar as a flexural reinforcement are limited to date. In this paper, the concrete shear contribution of the light weight concrete beam reinforced with GFRP bar was studied. Experiment for beams varying concrete compressive strengths and flexural reinforcement ratios was conducted and analysed. The test results showed that 75% of values obtained from proposed equation in preceding research were well agreed with the test results and were better results than the one predicted by the ACI 440.1R-06 code.

• Journal of the Korea institute for structural maintenance and inspection
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• v.4 no.3
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• pp.197-204
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• 2000

Tensile strength (stress) of bar splice is important in the research of mechanical behavior of reinforced concrete structures-beam, column etc.- with bar splice. The purpose of this research is to evaluate the flexural behavior - deflection of beam specimens, strain of main bars - of reinforced concrete beam with Lock Joint Coupler. To make a comparative research, reinforced concrete beam specimens with normal deformed bar and lap splice are tested and analyzed. Test results, Comparing a deflection of three types flexural specimens, a flexural specimen with Lock Joint Coupler is 40% greater than the other flexural specimens. At the center of flexural specimen, the strain of main bar(D29) with lock joint coupler is 50% less, and vice versa, at the point of 14cm far from the center of flexural specimen, the strain of main bar(D29) with lock joint coupler is 9% larger than the strain of main bar(D29) which calculated using the classical flexure theory. A discords, between a deflection behavior of the flexural specimens and a strain of the main bar, are caused by the difference of strain between the lock joint coupler and main bar, near the lock joint coupler. So, additional research is need to verify as stated above discords.

• Journal of the Korea Institute of Building Construction
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• v.4 no.1
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• pp.119-126
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• 2004

Generally, reinforced concrete is one of the most commonly used structural materials and it prevents corrosion of steel bar by high pH of interior, But, as time elapsed, reinforced concrete structure become deteriorated by many of combined deterioration factors and environmental conditions. And, there are large number of deteriorate mechanism of the reinforced concrete structure and it acts complexly. It is recognized that steel bar corrosion is the main distress behind the present concern regarding concrete durability. In this study, to institute combined deterioration environments, established acceleration condition and cycle for combined deterioration environments has a resemblance to environments which are real structures placed. After that to confirm corrosion properties of reinforced concrete due to permeability with covering depth and types of surface cover under combined deterioration environments, measured carbonation velocity coefficients, chloride ion diffusion coefficients, water absorption coefficients, air permeability coefficients and electric potential, corrosion area ratio, weight reduction, corrosion velocity of steel bar. The results showed that an increase in age also decrease carbonation velocity coefficients, increase Chloride ion diffusion coefficients and increases water absorption coefficients. As well, an increase in age also increases corrosion of steel bar. Data on the development of corrosion velocity of steel bar with types of surface cover made with none, organic B, organic A, inorganic B, and inorganic A is shown. As well, permeability and corrosion velocity of steel bar with covering depth is superior to 10mm than 20mm. And it is confirmed permeability and corrosion properties of steel bar are closely related.