• 한국산학기술학회논문지
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• 제8권2호
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• pp.348-353
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• 2007

본 연구에서는 중공형 섬유보강폴리머(Fiber Reinforced Polymer : FRP) 바닥판이 적용된 교량에 적합한 신축이음장치를 개발하고자 신축이음장치의 설계기준 및 특성을 분석하였다. 또한, 신축이음장치를 선정하는 기준이 되는 설계 신축량 산정법과 FRP바닥판 상세를 검토하여, 강콘크리트 거더 교량에 적용 가능한 FRP바닥판용 신축이음장치를 개발 제안하였다.

• Structural Engineering and Mechanics
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• 제53권6호
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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.

• Nuclear Engineering and Technology
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• 제55권8호
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• pp.3039-3045
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• 2023

Fiber-reinforced polymer (FRP) composites are considered suitable candidates for structural materials of spacecrafts due to their excellent properties of high strength, light weight, and corrosion resistance. An online health monitoring method for FRP composites must be applied to space structures. However, the application of existing health monitoring methods to space structures is limited due to the harsh space environment. Here, carbon fiber-reinforced polymer (CFRP) composites embedded with fiber Bragg grating (FBG) sensors were prepared to explore the feasibility of strain monitoring using embedded FBG sensors in γ-radiation environment. The analysis of the influence of radiation on the strain monitoring demonstrated that the embedded FBG can be successfully applied to the health monitoring of FRP composites in radiation environment.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.114-117
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• 2006

Concrete beams reinforced with fiber reinforced polymer (FRP) bars exhibit large deflection and crack width as compared to concrete beams reinforced steel due to modulus of elasticity of FRP bars. Current design code for prediction and crack width developed in concrete structures reinforced with steel bars may not be used for concrete beams reinforced with FRP bars. Thus a number of researcher have attempted to propose modifications to the ACI 318 empirical equation for estimating the effective moment of inertia of reinforced concrete beams. Others used numerical method to calculate the deflection. The purpose of this paper is to evaluation of methods of ACI 440.1 R-01, ISIS Canada design manual, and others for predicting deflection for glass fiber reinforced polymer reinforced concrete beams.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.509-510
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• 2009

FRP 시트를 사용한 철근콘크리트 보의 보강은 섬유의 선형 응력-변형률 거동으로 인한 취성파괴 가 일어난다. 본 연구에서는 두 가지 섬유를 사용하여 하이브리드 FRP 시트를 연구하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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• pp.401-404
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• 2004

In recent years, the use of fiber reinforced polymer (FRP) composites to repair or strengthen existing reinforced concrete (RC) structures is increasing In order to evaluate the shear strengths of RC structures strengthened by FRP composites, it is needed to understand the shear failure modes of these structures. This paper presents a rational equation to distinguish the shear fail modes of RC structures strengthened by FRP composites using the compatibility aided truss models.

• 콘크리트학회논문집
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• 제19권6호
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• pp.727-734
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• 2007

철근과 fiber-reinforced polymer (FRP)의 물리적, 역학적 특성의 차이 및 슬래브 상부 보강재의 기둥 인접부 집중 배근, 그리고 기둥 인접부 슬래브에 강섬유 콘크리트 (SFRC)의 타설 등에 따른 2방향 슬래브의 펀칭 전단 거동에 대한 효과를 평가하였다. 펀칭 전단강도, 강성, 연성, 변형률 분포 그리고 균열 제어 성능 등을 파악하였다. 실험 결과 기둥 인접부의 슬래브에 집중 배근을 하거나 SFRC를 타설하는 것은 glass fiber-reinforced polymer (GFRP) 바로 보강된 슬래브의 펀칭 전단 거동을 향상시켰다. 기둥 인접 구역에 집중 배근된 슬래브의 실험 결과를 다양한 설계기준과 타 연구자에 의해 제안된 예측식과 비교하였으며, 집중 배근으로 인한 이점을 예측식에 반영할 수 있도록 집중 배근된 슬래브의 철근비를 산정하는 합리적인 방법도 제안하였다.

• 한국전산구조공학회논문집
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• 제21권4호
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• pp.365-373
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• 2008

섬유복합재료(Fiber Reinforced Polymer, FRP)는 경량성, 높은 설계기준강도, 비전기 비자성 및 내부식성의 특징 등으로 인하여 최근 건설분야에서 많은 연구가 진행되고 있다. 그 중 GFRP(Glass Fiber Reinforced Polymer)는 가격 경쟁성에서 우수하여 일반적으로 많이 사용되고 있다. 그러나 GFRP는 상대적으로 낮은 탄성계수를 가지고 있어 처짐이 과대하게 발생함으로 구조부재 단면으로서 활용되기 위해서는 단면이 커야하며, 설계시 사용하중에 의한 처짐 제한에 대한 검토를 실시해야 한다. 이에 본 연구에서는 언급된 기술적인 문제점을 해결하기 위하여 대형 단면의 적용이 가능하도록 모듈형식의 단면을 제안하였다. 그리고 FRP의 낮은 강성을 확보하군 위하여 콘크리트를 충진하는 새로운 FRP+콘크리트 합성 거더 형상을 개발하였다. 개발된 FRP)콘크리트 합성 거더의 전단지간비와 콘크리트 충진 여부에 따른 전단강도 및 처짐, 중립축 변화를 확인하고자 전단실험을 실시하였다.

• Structural Engineering and Mechanics
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• 제88권6호
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• pp.599-608
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• 2023

The present study is focused on instigation of the nonlinear mechanical behavior of reinforced concrete beams considering different types of FRP bars through nonlinear finite element simulations. To explore the impact of the FRP reinforcement type and geometry on the nonlinear mechanical behavior of reinforced beam, intensive parametric studies are carried out and discussed. Twenty models were carried out based on the finite element software (ABAQUS). The concrete damage plasticity model was considered. Four types of fiber polymer bars, CFRP, GFRP, AFRP and BFRP as longitudinal reinforcement for concrete beam were used. The validation of numerical results was confirmed by experimental as well as numerical results, then the parametric study was conducted to evaluate the effect of change in different parameters, such as bar diameter size, type of FRP bars and shear span length. All results were analyzed and discussed through, load-deflection diagram. The results showed that the use of FRP bars in rebar concrete beam improves the beam stiffness and enhance the ultimate load capacity. The load capacity enhanced in the range of (20.44-244.47%) when using different types of FRP bars. The load-carrying capacity of beams reinforced with CFRP is the highest one, beams reinforced with AFRP is higher than that reinforced with BFRP but beams reinforced with GFRP recorded the lowest load of capacity compered with other beams reinforced with FRP Bars.

• 한국안전학회지
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• 제24권3호
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• pp.39-46
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• 2009

A recent and promising method for shear strengthening of reinforced concrete(RC) members is the use of near surface mounted(NSM) fiber reinforced polymer(FRP) reinforcement. In the NSM method, the reinforcement is embedded in grooves cut onto the surface of the member to be strengthened and filled with an appropriate binding agent such as epoxy paste or cement grout. This paper illustrates a research program on shear strengthening of RC beams with NSM channel-type FRP beams which is developed in this study. The objective of this study is to clarify the role of channel-type FRP beam embedded to the beam web for shear strengthening of reinforced concrete beams. Included in the study are effectiveness in terms of spacing and angle of channel-type FRP beams, strengthening method, and shear span ratio. the study also aims to understand the additional shear capacity due to glass fiber reinforced polymer beams and carbon reinforced polymer beams. And anther objective is to study the failure modes, shear strengthening effect on ultimate force and load deflection behavior of RC beams embedded with channel-type FRP beams on the shear region of the beams.