• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.1
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• pp.75-83
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• 2014

In order to prevent brittle failure of concrete, steel fiber reinforcement is effective composite material. However ductility of steel fiber reinforced concrete may be limited due to shrinkage caused by large content of cement binder. Chemical prestressing for steel fiber reinforcement in cement matrix can be induced through expansive admixture and this can increase reinforcing effect of steel fiber. In this study, mechanical performances in concrete with CSA (Calcium sulfoaluminate) expansive admixture and steel fiber reinforcement are evaluated. For this work, steel fiber reinforcement of 1 and 2% of volume ratio and CSA expansive admixture of 10% weight ratio of cement are added in concrete. Mechanical and fracture properties are evaluated in concrete with steel fiber reinforcement and CSA expansive admixture. CSA concrete with steel fiber reinforcement shows increase in tensile strength, initial cracking load, and ductility performance like enlarged fracture energy after cracking. With appropriate using expansive admixture and optimum ratio of steel fiber reinforcement, their interactive action can effectively improve brittle behavior in concrete.

• Proceedings of the Korean Geotechical Society Conference
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• 2003.03a
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• pp.867-874
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• 2003

섬유보강재를 이용한 성토제체의 설계에서 기존의 방법은 보강재의 변형을 무시하고 흙의 변형만을 중요시하고 있다. 보강재에 의해 보강된 성토제체의 파괴면에서 보강재와 흙의 거동은 초기응력단계에서는 일체거동현상을 나타내지만 응력의 증가에 따라 변형량에서 차이를 보인다. 이러한 문제는 토공구조물의 보강재를 설계하는데 있어서 중요한 요소로서 보강효과에 큰 영향을 미칠 수 있다. 본 연구에서는 연약지반 위에 PET Mat로 보강하여 축조한 성토제체에서 보강재와 흙의 응력 - 변형거동을 수치해석을 통하여 분석하였다. 연구결과, 파괴면에서 보강재의 변형은 보강재의 인장강도 크기에 따라 큰 차이를 보이고 있다. 외부하중에 의해 보강재에 발생하는 최대응력은 보강재의 항복인장강도를 초과하지 않으며, 보강재에 발생하는 응력이 성토체에서 발생하는 응력이상일 때 이상적인 것으로 나타났다. 또한 제체의 전단파괴에 대한 안전율은 보강재의 항복인장강도가 증가할수록 증가하는데 보강재와 흙의 변형이 일치되는 이후부터는 안전율의 증가율은 거의 미미한 것으로 나타났다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.3
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• pp.53-59
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• 2018

This study analyzed the field applicability through the combination of environment-friendly grid-typed reinforcements and pre-mixed fiber with filler. The film of the grid-typed reinforcement is made by recycled PE resin. And, Ascon fiber is obtained the dispersion by pre-mixing of filler. To be able to recognize in advance the various circumstances that could arise in the construction of the road pavement layer, we conducted a basic field application test of the (Mock Up) pavement layer. As a result, it was found that the pavement with environment-friendly grid-typed reinforcement and dispersive fiber construction had improved strength, stress, and rutting resistance. It is consistent with the strength and stress results of the actual test of the mock up specimen. It is expected to perform an effective role in the safety as well as the use of environment-friendly fibers in actual construction.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.77-78
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• 2008

최근 이산화탄소 흡수원으로 해조류의 배양과 이산화탄소 고정에 대한 영향 분석연구가 세계적으로 활발하게 진행되고 있다. 또한, 해조류에서 바이오에너지를 얻기 위한 연구와 해조류의 구성성분인 섬유, 당 및 지질을 이용하기 위한 연구도 다양하게 진행되고 있다. 해조류 섬유는 주로 종이 및 바이오복합재료 제조에 사용되며 추출물은 식품 등에 사용될 수 있다. 특히, 해조류 섬유는 셀룰로오스 섬유와 유사한 특성을 가지기 때문에 바이오복합재료의 천연섬유 보강재로서 사용이 가능하다. 바이오복합재료는 천연섬유를 보강재로 사용한 에너지절약과 친환경 특성을 가진 고분자복합재료로서 현재 자동차 및 건축물의 내장재로 사용되고 있는 유리섬유 보강 고분자복합재료를 대체할 수 있는 신소재이다. 본 논문에서는 해조류 기반 친환경 에너지소재의 세계적 연구동향 및 해조류 섬유를 이용한 신소재 개발연구로서 홍조류 섬유 보강 바이오복합재료에 대한 연구결과를 소개하고자 한다.

• Korean Journal of Materials Research
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• v.5 no.3
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• pp.316-323
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• 1995

페놀수지 결합재에 PAN섬유(PF), PAN계 탄소섬유(CF) 그리고 아라미드 섬유(AF)를 보강재로 사용하여 단일섬유 보강복합재를 제조하였으며 이들 섬유를 각각 두 종류씩 혼성하여 혼성섬유 보강복합재를 제조하였다. 각 보강복합재를 섬유의 보강분율에 따른 마찰 및 마모특성을 시험하였다. CF 보강복합재(CFRP)가 마찰계수와 마모량이 가장 낮게 나타났으며, PF 보강복합재(PFRP)는 가장 높은 마찰계수와 마모량을 나타내었다. PF에 CF나 AF를 보강한 혼성복합재의 경우 마찰계수가 0.311~0.328로 혼성비에 따라서는 큰 차이를 보이지 않은 반면, PF의 보강분율이 증가할수록 마모량은 증가하였다. CF와 AF를 보강한 혼성복합재의 마찰계수는 0.264~0.309로 가장 낮게 나타났고, AF의 보강분율이 증가함에 따라 마찰계수는 증가하는 양상을 나타내었으며, 가장 적은 마모량과 함께 안정된 마모형태를 보였다.

• Korean Journal of Materials Research
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• v.4 no.7
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• pp.733-740
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• 1994

Oxidized-PAN fiber reinforced composite(OFRP), carbon fiber reinforced composite(CFRP), aramid fiber reinforced composite(AFRP), and glass fiber reinforced composite(GFRP) were fabricated with phenolic resin matrix by hot press molding. We tested the friction coefficient and wear rate varying with fiber weight fraction and observed the effect of fibers according to characteristics of individual reinforcement. When the amount of aramid fiber was 45wt%, average friction coefficient was maximum value of 0.353~0.383, where as, when the amount of pitch based carbon fiber was 45wt%, average friction coefficient was the lowest value of 0.164~0.190. The wear rate of AFRP and CFRP was low, but that of GFRP and OFRP increases drastically in the case of increasing of fiber weight fraction. Wear diagram of OFRP was unstable, but that of CFRP and AFRP was a bit stable. Through very unstable diagram of GFRP, we found that friction stability of GFRP was the lowest.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.177-182
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• 1999

사용한 보수.보강재, Rod, Fabric, Strand 형상을 콘크리트 구조물등에 보강재로 사용되어왔다. 이 재료는 해양환경하에서 내식성과 내구성을 갖는 철근및 철골대체용 복합소재와 초고층 경량 연속섬유보강 시멘트 복합재료는 탄소섬유, 아라미드섬유, 유리섬유등의 쉬트(sheet)형상을 신건재, 비자성, 비전도성, 전파차폐용 재료등에 사용할수있다. 그러나 FRP Rod를 내식성이 요구되는 철근 및 철골대체재로 사용할 경우에는 폴리머 매트릭스의 열화, 섬유와 폴리머간 계면 접착강도의 한계, 화재시 내화성, 보강재의 인발성등의 단점들을 갖고있다[1]. (중략)

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.861-867
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• 2015

The Compact Tension (CT) type test was performed in order to evaluate the fracture toughness performance of glass fiber-reinforced laminated timber. Glass fiber textile and sheet Glass fiber reinforced plastic were used as reinforcement. The reinforced laminated timber was formed by inserting and laminating the reinforcement between laminated woods. Compact tension samples are produced under ASTM D5045. The sample length was determined by taking account of the end distance of 7D, and bolt holes (12 mm, 16 mm, 20 mm) had been made at the end of artificial notches in advance. The fracture toughness load of sheet fiberglass reinforced plastic reinforced laminated timber was increased 33 % in comparison to unreinforced laminated timber while the glass fiber textile reinforced laminated timber was increased 152 %. According to Double Cantilever Beam theory, the stress intensity factor was 1.08~1.38 for sheet glass fiber reinforced plastic reinforced laminated timber and 1.38~1.86 for glass fiber textile reinforced laminated timber, respectively. That was because, for the glass fiber textile reinforced laminated timber, the fiber array direction of glass fiber and laminated wood orthogonal to each other suppressed the split propagation in the wood.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.797-800
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• 2008

To decrease the usage of cement, the pozzolan reaction materials are used as a mineral admixture. Hwang Toh which is broadly deposited in Korea is well known as a environment friendly material and the activated Hwang Toh which has the property of pozzolan reaction is practically used as a mineral admixture of concrete. PET fiber which is made by recycled PET bottle controls micro crack in concrete. But the study about concrete mixed with reinforcing fiber is not enough and the property of Hwang Toh concrete mixed with PET fiber is more complicated case. So this study performed drying shrinkage experiment to analyse mechanical property of Hwang Toh concrete mixed with PET fiber.

• Journal of the Society of Disaster Information
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• v.14 no.4
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• pp.492-500
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• 2018

Purpose: In this paper, based on this background, the main purpose of studying the behavior of concrete slab reinforced with new material fiber in impact loading is investigated by AFRP using aluminum fiber. Results: Research on the use of new materials as reinforcing materials for concrete members has been carried out in many fields such as flexural and shear tests under static loading, fatigue loading under cyclic loading, and application to PC beams. However, And the issue of plate elements is still at a basic stage. Conclusion: In this paper, the dynamic behavior of reinforced concrete slabs is investigated by using AFRP rod reinforced with aluminum fiber.