• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.585-590
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• 2001

The structural characteristics of concrete-filled glass fiber reinforced polymer tubes were studied. The concept of concrete-filled composite columns was introduced to overcome the corrosion problems associated with steel and concrete piles under severe environments. Other benefits of composite columns include low maintenance cost, high earthquake resistance, and long expected endurance period. Several experiments were conducted; 1) compression test for short-length composite columns, 2) uniaxial compression tests on a total of 7 columns with various slenderness ratios. Short-length columns give higher strength and ductility revealing high confinement action in concrete. Failure strengths, failure patterns, confinement effects, and stress-strains relations were analyzed for slender columns. Current study will show the feasibility of concrete-filled glass fiber reinforced polymer composite columns in corrosive environments, and will provide an experimental database for columns that are externally reinforced by multidirectional fibers.

• 한국농공학회논문집
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• 제46권6호
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• pp.37-45
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• 2004

In this study, twelve different glass fiber reinforced polymer concrete composite panel specimens with various rib heights and tensile side and reinforced side thickness were produced, and the flexural tests were conducted to figure out the effect of The height and thickness influencing on the flexural properties of composite panel. Test results of the study are presented. Especially, a prediction equation of the ultimate moment based on the strength design method agrees well with the test results, and it is thought to be useful for the corresponding design of cross-section according to various spans as the glass fiber reinforced polymer concrete composite panel is applied for a permanent mold.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.493-494
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• 2008

During the last years hollow core insulators started their success story in the field of high voltage engineering for electrical apparatus, substituting porcelain insulators. The termination, also named top and bottom fittings are used for the connection to the rest of the electrical apparatus. The top and bottom flange are attached to the composite to transmit mechanical load and also ensure the gas tightness. They are bonded by epoxy glue with a glass transition temperature of about $130^{\circ}C$-$150^{\circ}C$ the glass reinforced epoxy tube of filament winding. This paper describes the results of a study on the bonded joints of fiber reinforced epoxy tube and cast aluminum. This suggests that surface roughness and glue types play an important role in evaluating of gas sealing capability on the flange and fiber reinforced epoxy tube in the composite hollow bushing.

• Composites Research
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• 제13권3호
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• pp.1-8
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• 2000

Excellent environmental durability and handy installation procedure as well as high specific strength and stiffness have introduced fiber-reinforced polymeric composite materials into the civil and architectural engineering field. This study presents the considerably enhanced strength characteristics of the mortal beams by being reinforced with epoxy-bonded carbon fiber sheets(CFS). Three point bending and Charpy impact tests were performed on both of bare and reinforced mortar specimens. The influences of length, and the number of reinforcing plies were investigated. Strength reduction due to pre-existent notch was lessened dramatically. The acoustic emission(AE) measurement revealed the progressive damage process in reinforced specimens.

• 한국세라믹학회지
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• 제48권5호
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• pp.373-378
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• 2011

The composite added with surface-coated chopped carbon fiber showed the microstructure of a 3 dimensional discretional arrangements. The fiber reinforced reaction bonded silicon carbide composite, containing the 50 vol% carbon fiber, showed the porosity of < 1 vol%, 3-point bending strength value of 250MPa and fracture toughness of 4.5 $MPa{\cdot}m^{1/2}$. As the content of carbon fiber was increased from 0 vol% to 50 vol% in the composite, fracture strength was decreased due to the increase of carbon fiber, which has a less strength than SiC and molten Si. On the other hand, the fracture toughness was increased with increasing the amount of carbon fiber. According to the polished microstructure, carbon fiber was shown to have a random 3 dimensional arrangement. Moreover, the fiber pull-out phenomenon was observed with the fractured surface, which can explain the increased fracture toughness of the composite containing high content of carbon fiber.

• 대한기계학회논문집
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• 제18권4호
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• pp.887-902
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• 1994

Within the framework of anisotropic thermoelasticity, the problem of an interlaminar crack in a laminated fiber-reinforced composite subjected to a uniform heat flow is investigated. Under a state of generalized plane deformation, dissimilar anisotropic half-spaces with different fiber orientations are considered to be bound together by a matrix interlayer containing the crack. The interlayer models the matrix-rich interlaminar region of the fibrous composite laminate. Based on the flexibility/stiffness matrix approach, formulation of the current crack problem results in having to solve two sets of singular integral equations for temperature and thermal stress analyses. Numerical results are obtained, illustrating the parametric effects of laminate stacking sequence, relative crack size, crack location, crack surface partial insulation, and fiber volume fraction on the values of mixed mode thermal stress intensity factors.

• 구강회복응용과학지
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• 제22권1호
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• pp.23-27
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• 2006

This case reports describe a new approach to the use of polymers in orthodontics, using a fiber reinforced composite(FRC). FRC was successfully used in a periodontal splints, fiber post for endodontic use, orthodontic retainer and space maintainers, implant prosthesis, large span bridge, management of cracked tooth, anchorage reinforcement in orthodontics. FRC has highly favorable mechanical properties, and its strength-to-weight ratios is superior to those of most alloys. FRC has potential for use in many applications in dentistry and is expected to gain increasing application and popularity in dentistry. These case reports show that FRC is a promising anchorage reinforcement material for use in orthodontic practice.

• 한국재료학회지
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• 제4권7호
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• pp.733-740
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• 1994

페놀수지 결합재에 보강섬유의 종류에 따라서 내염섬유 보강 복합재(OFRP), 탄소섬유 보강 복합재(CFRP), 유리섬유 보강 복합재(GFRP), 아라미드 섬유 보강 복합재(AFRP)를 제조하였다. 각 보강섬유의 분율을 달리함에 따라 마찰계수 및 마모율을 측정하여 각 보강섬유의 특성이 미치는 영향을 관찰하였다. 아라미드의 섬유량이 45tw%일 때 평균 마찰계수가 0.353-0.383으로 가장 높게 나타난 반면에 핏치계 탄소섬유를 45wt% 보강한 경우 0.164-0.190으로 가장 낮게 나타났다. AFRP와 CFRP의 마모율은 낮게 나타내었으며, GFRP와 OFRP는 섬유분율이 증가함에 따라 급격히 증가하는 양상을 보였다. OFRP는 마모 diagram이 불안정하였으며 CFRP와 AFRP는 대체적으로 안정한 형태를 나타내었다. GFRp는 상당히 불안정한 마모diagram을 나타낸 것으로 보아 마찰 안정성이 가장 떨어짐을 알 수 있었다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.410-414
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• 2004

Under longitudinal loading continuous fiber reinforced metal matrix composite(MMC) have interpreted an outstanding performance. However, the applicability of continuous fiber reinforced MMCs is somewhat limited due to their relatively poor transverse properties. Therefore, the transverse properties of MMCs are significantly influenced by the properties of the fiber/matrix interface. In this study, elastic-plastic behavior of transversely loaded unidirectional fiber reinforced metal matrix composites investigated by using elastic-plastic finite element analysis. Different fiber placement(square and hexagon) and fiber volume fractions were studied numerically. The interface was treated as three thin layer (with different properties) with a finite thickness between the fiber and the matrix. The analyses were based on a two-dimensional generalized plane strain model of a cross-section of an unidirectional composite by the ANSYS finite element analysis code.

• 대한기계학회논문집A
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• 제30권12호
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• pp.1518-1525
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• 2006

Finite element analyses of structures made of the fiber reinforced composites require an adequate method to characterize the high anisotropic behavior induced by one or several layers of fiber cords with different spatial orientation embedded in a rubber matrix. This paper newly proposes a continuum based rebar element considering change of the orientation of the fiber during deformation of the composite. The mechanical behavior of the embedded fiber is modeled using two-node bar elements in order to consider the relative deformation and spatial orientation of the embedded fiber. For improvement of the analysis accuracy, the load-displacement curve of fiber is applied to the stiffness matrix of fiber. A finite element program is constructed based on the total Lagrangian formulation considering both geometric and material nonlinearity. Finite element analyses of the tensile test are carried out in order to evaluate the validity of the proposed method. Analysis results obtained with the proposed method provides realistic representation of the fiber reinforced rubber composite compared to results of other two models by the Halpin-Tsai equation and a rebar element in ABAQUS/Standard.