• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.453-456
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• 2008

섬유보강재는 부식에 대한 저항성이 높고, 고강도이며, 또한 강도에 대한 중량비(섬유보강재의 중량은 보강철근의 약 1/4정도)가 매우 낮아서 구조물 및 내하력이 저하된 콘크리트구조물의 보강에 따른 추가적인 중량의 증가 없이 보강을 할 수 있는 장점을 가지고 있다. 그러나 섬유보강재는 하중을 가하면, 최대 응력점까지 응력이 선형적으로 증가하다가 파괴되는 취성적 성질을 가지고 있다. 이러한 단점을 보완하기 위해 여러 섬유를 혼합하여 하이브리드화된 섬유보강재를 개발하였다. 개발된 하이브리드 섬유보강재는 유리섬유와 탄소섬유를 혼합하여 바 형태로 제작했으며, 유리섬유에 대한 탄소섬유의 체적비는 약 9 : 1로 구성이 된다. 하이브리드 섬유보강재를 타격식 앵커를 사용하여 시험체를 보수한 다음 인발 및 휨 시험을 실시하여 정착앵커의 수에 대한 시험체의 거동을 분석하였다. 본 연구에서는 타격식 앵커를 이용한 하이브리드 섬유보강재로 보강된 구조물의 보강특성을 알아보는데 목적이 있다.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2003년도 추계학술발표대회 논문집
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• pp.42-45
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• 2003

Nondestructive damage sensing and mechanical properties for acid-treated carbon nanotube (CNT) and nanofiber (CNF)/epoxy composites were investigated using electro-micromechanical technique and acoustic emission (AE). Carbon black (CB) was used to compare to CNT and CNF. The results were compared to the untreated case. The fracture of carbon fiber was detected by nondestructive acoustic emission (AE) relating to electrical resistivity under double-matrix composites test. Sensing for fiber tension was performed by electro-pullout test under uniform cyclic strain. The sensitivity for fiber damage such as fiber fracture and fiber tension was the highest for CNT/epoxy composites. Reinforcing effect of CNT obtained from apparent modulus measurement was the highest in the same content. For surface treatment case, the damage sensitivity and reinforcing effect were higher than those of the untreated case. The results obtained from sensing fiber damage were correlated with the morphological observation of nano-scale structure using FE-SEM. The information on fiber damage and matrix deformation and reinforcing effect of carbon nanocomposites could be obtained from electrical resistivity measurement as a new concept of nondestructive evaluation.

• 한국건축시공학회지
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• 제8권5호
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• pp.43-51
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• 2008

This study examines shear capacity performance and structural characteristics of reinforced concrete beam using carbon fiber sheet(CFS), g)ass fiber sheet(GFS), glass fiber steel plate(GSP) and carbon fiber bar CB) which are reinforcing materials for reinforced concrete beam in order to produce similar condition to repair and reinforce actual structure and aims to provide data available In designing and constructing reinforced concrete structures under the structural damage. This study obtains the following conclusions. After considering the shear experiment results. it was indicated that the CB reinforced test object was the best in the shear capacity improvement and ductility capacity as it was contained in the concrete and was all operated, Also, GFS reinforced test object indicated the reduced flexural capacity but good shear capacity. GSP reinforced test object had bigger reinforcing strength than other reinforcing test objects. On the other hand, it showed the lowest reinforcement effect as compared section thickness of reinforced material because it showed the bigger relativity a section thickness of reinforced material. If the adherence to the concrete is improved, it will seem to show bigger reinforcement effect.

• 한국재료학회지
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• 제4권7호
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• pp.817-822
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• 1994

비슷한 역학적 특성을 갖는 단면의 형상이 C형인 탄소섬유와 전형적인 원형탄소섬유를 에폭시를 모재로 하여 상호의 단면 형상이 강화 효과에 미치는 영향을 실험하였다. 실험결과 C 형 탄소 섬유 강화 복합재가 굴곡강도(218%), 굴곡탄성률(223%), 충간전단강도(157%), 충격강도(227%), 횡굴곡강도(184%)등의 모든 기계적 특성 부분에서 우수한 성능을 보였으며, 또한 재료의피로수명, 마찰/마모계수와 같은 기계적 특성과도 많은 상관을 보이는 것으로 알려진 제진(damping)특성에 있어서도 약 185% 정도의 높은 값을 보였다. 본 연구팀은 이와 같은 비원형 탄소섬유(C형)의 강화 효과및 가능성을 확인하여 제시하는 바 이다.

• 섬유기술과 산업
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• 제1권1호
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• pp.97-106
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• 1997

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.587-592
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• 2002

This study attempts to calculate tile nominal flexural strength of reinforced concrete beam with carbon fiber sheets by tile 27 cases which have three steel ratios and four reinforcing ratios. Based on the result, application possibilities of strength design method to estimate the nominal moment is investigated and valuable data of carbon fiber sheets for reinforcing design will be discussed.

• 한국구조물진단유지관리공학회 논문집
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• 제19권3호
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• pp.139-148
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• 2015

본 논문은 강섬유 대신 철근집합체를 사용하여 초고강도 섬유보강 콘크리트 부재의 최대하중 이후 연성거동을 유도하는 것을 목적으로 한다. 강섬유와 철근집합체의 조합을 가진 직사각형 콘크리트 보에 대한 휨거동 실험을 수행하였다. 강섬유의 혼입률은 0%, 0.7%, 1%, 1.5%, 2%이고, 연성거동을 유도하기 위한 종방향 철근 집합체의 철근비는 0.0036, 0.016, 0.028 그리고 0.036이다. 이러한 실험 요소의 조합으로 15개의 초고강도 콘크리트보가 제작되었다. 강섬유 뿐만 아니라 종방향의 철근 집합체도 초고강도 콘크리트보의 연성거동을 유도하는데 효과를 가지고 있다. 강섬유 혼입률 0.7%와 철근비 0.028인 철근집합체를 사용할 경우 가장 경제적인 조합임을 볼 수 있다. 하중과 처짐관계, 콘크리트 응력의 변화 및 균열양상 등이 좁은 간격을 가진 작은 직경의 종방향 철근 집합체의 유용성을 나타내고 있다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
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• pp.11-12
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• 2003

The reinforcing effect of single wall carbon nanotubes (SWNTs) on polyacrylonitrile (PAN) fiber were investigated. The tensile fracture images of the composite fibers demonstrate that SWNTs are well dispersed in PAN matrix as bundles (ropes) ca. 20nm in thickness. It was found that SWNTs play a role not only to reinforce but also to toughen the PAN fiber by increasing breaking strain as well as modulus and strength of the fiebrs. The composite fibers exhibited improved dimensional stability at elevated temperature compared to the neat PAN fiber.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2022년도 봄 학술논문 발표대회
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• pp.178-179
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• 2022

This study evaluated the crack reduction characteristics of concrete by type of fiber reinforced concrete. As a result of the experiment, it was shown that the fluidity decreased due to the mixing of the fiber reinforcing material. The higher the amount of fiber reinforced material used, the higher the decrease in fluidity. It was confirmed that the tensile strength was improved by the mixing of the fiber reinforcing material. The selection of fiber reinforcement has a great influence on the crack reduction effect.

• 한국산업융합학회 논문집
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• 제11권2호
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• pp.93-98
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• 2008

Steel fibre reinforced concrete (SFRC) were considered a new technology for the construction industry. However today this technology has found wider acceptance among the construction industry. Currently, steel fibres are used in varied segments in many application areas across different segments in the construction industry, especially in tunneling, airports, warehouses, etc. Time and safety are the main factors are among the various advantages which renders steel fibres superior to the competing product. For fibers reinforcing, The maximum load carrying capacity is controlled by fibers pulling out of the composite because fiber reinforcing does not have a deformed surface like larger steel reinforcing bars. The study demonstrated that above concept is applicable and effective in concrete structure by analytical study. The analytical result appears that SFRP have the potential to significantly increase the strength of existing concrete structures, while at the same time dramatically improving their fracture energy characteristics.