• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.481-482
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• 2010

There is disagreement among researchers in many areas of FRP RC design code except flexural. So a new efficient and reliable shear strength equation which show a high accuracy and a consistent variation in predicting failure modes and shear strength was proposed.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.908-911
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• 2003

This study was performed to verify the effect of reinforcement of RC Beams strengthened($90^{\circ}$ strip type) by FRP(CFRP) and Predited the shear strength of them using the upper bound theorem. The prediction model was confirmed with the result of the FEM analysis. The analyzed result showed thar shear-damaged RC beams by strengthened by FRP was improved their shear capacity.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.121-124
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• 2006

This study focuses on the flexural behavior of RC beam with externally bonding FRP reinforcement. FRP-plate strengthening system is mainly installed with an anchor-bolt. But the installation with it has several disadvantage as a complicated work, a high labor costs. To complement these disadvantage, the test is performed about improved FRP-plate strengthening system.

• Composites Research
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• v.21 no.5
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• pp.1-8
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• 2008

In recent years, the reversed L-shaped perforated shear connector has been developed to mitigate the problem associated with headed stud and Perforbond shear connector and to simulate the simultaneous failure of concrete and shear connector. And FRP perforated shear connector has been applied to composite concrete and FRP module in the FRP-concrete composite bridge deck. The design criterion of the reversed L-shaped and FRP perforated shear connector has not been established yet since the lack of experimental and analytical study results. In this paper, the existing design equations for the Perforated were briefly discussed and the equation fur the prediction of shear resisting capacity of the reversed L-shaped and FRP perforated shear connector was suggested based on the experimental test, FEM analysis. and the existing equation for the Perfobond. The predict results obtained by the suggested equation arc compared with the experimental results, the applicability and effectiveness of suggested equation was verified.

• Journal of the Korea Concrete Institute
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• v.17 no.6 s.90
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• pp.983-992
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• 2005

The shear failure modes of fiber reinforced polymer(FRP) strengthened concrete beams are quite different to those of the beams strengthened with steel stirrups. When the beams are strengthened with larger amount of FRP composites, the beams normally fail in shear due to concrete crushing before the FRP reaches its rupture strain. In order to predict the shear strength of such beams, the actual rupture strain must be known. The equations previously reported in the technical literature adopt an effective reduction factor for the rupture strain. These equations may not be applicable to FRP strengthened RC beams that are beyond the experimental application limits, because most of these equations are empirical in nature. This paper presents the results of an analytical study on the performance of reinforced concrete beams externally wrapped with FRP composites and internally reinforced with conventional steel stirrups.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.349-352
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• 2006

Pull-off test is generally used as a method of evaluating bond strength of FRP with concrete at the job site. However, pull-off test damages FRP composites and the maximum pull-off strength is limited up to tensile strength of concrete. Accordingly, it is required to set-up a test method that can simply evaluate bond performance of structural adhesive. This study suggested compression and bending test of epoxy resin as test methods that can indirectly evaluate performance of adhesive, as well as standardized test specification for different types of specifications from various countries. In this study, the section dimension of compression and bending test specimens is unified, and standard test specimen size is achieved by test results.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.133-141
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• 1998

FRP는 비부식성 및 고강도의 뛰어난 성질에도 불구하고 콘크리트 구조에 사용하는 데 있어서 소성의 결핍 및 낮은 전단강도와 같은 몇가지의 기술적인 단점을 가지고 있다. 특히 이 두가지 성질은 프리스트레스트 콘크리트보에 있어서 다우얼 작용이 일어나는 전단균열 단면에서와 같이 인장과 전단의 복합효과가 일어날 때 텐던의 조기 파괴를 일으키기 쉽다. 본 논문에서는 탄소 FRP연선을 사용한 프리스트레스트 콘크리트보에서의 텐던파열에 의한 전단파괴를 연구하였다. 전단시험 결과에 의하면 전단 텐던 파괴는 FRP를사용한 프리스트레스트 보에서만 일어나는 유일한 파괴형식으로 보의 전단강도를 저감시키는 것으로 확인되었다. 이러한 전단 텐던 파괴 과정을 규명하기 위하여 다우얼 시험을 실시하고 최초로 실용적인 시험장치 및 과정을 소개하였다. 다우얼 시험 결과에 의하면 FRP 연선은 인장과 전단의 상호작용에 의해 Tsai-Hill 파괴 기준에 따라 파괴되었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.43-44
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• 2010

We developed a new FRP-concrete composite deck applicable to a cable-stayed bridge, and applied to a trial bridge for test purpose. From this trial construction, we verified constructability and structural performances of this deck system.

• Structural Engineering and Mechanics
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• v.53 no.6
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• pp.1253-1269
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• 2015

The present paper investigates the post heating behavior of concrete beams reinforced with fiber reinforced polymer (FRP) bars, namely carbon fiber reinforced polymer (CFRP) bars and glass fiber reinforced polymer (GFRP) bars. Thirty rectangular concrete beams were prepared and cured for 28 days. Then, beams were either subjected (in duplicates) to elevated temperatures in the range (100 to $500^{\circ}C$) or left at room temperature before tested under four point loading for flexural response. Experimental results showed that beams, reinforced with CFRP and GFRP bars and subjected to temperatures below $300^{\circ}C$, showed better mechanical performance than that of corresponding ones with conventional reinforcing steel bars. The results also revealed that ultimate load capacity and stiffness pertaining to beams with FRP reinforcement decreased, yet their ultimate deflection and toughness increased with higher temperatures. All beams reinforced with FRP materials, except those post-heated to $500^{\circ}C$, failed by concrete crushing followed by tension failure of FRP bars.

• Steel and Composite Structures
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• v.1 no.2
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• pp.231-244
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• 2001

The strengthening of reinforced concrete structures using externally bonded steel or advanced fibre reinforced plastic (FRP) composites is becoming increasingly common. A key factor affecting the behaviour and reliability of such strengthened structures is the bond strength between the steel or FRP plate and the concrete substrate. Several different experimental set-ups have previously been used to determine bond strength. This paper presents a careful finite element analysis of the stress distributions in these test set-ups. Results show that stress distributions can be significantly different for different set-ups, for similar materials and geometry.