• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.167-168
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• 2010

This study considered applications of FRP panels as curved structural members. Also, curved GFRP panel with open cell type for tunnel lining was manufactured by pultrusion method through improving equipments.

• Journal of Korean Society of Steel Construction
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• v.18 no.5
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• pp.615-624
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• 2006

In the present paper, an extended composite beam theory that has no restriction on the lay-up and can account for Poisson effect which is significant for composite materials is proposed. Buckling equations for composite thin-walled members which are subjected to axial compression are derived based on the composite beam theory. In order to check the validity of the derived buckling equations, the results of experiments on the flexural-torsional buckling of vinylester/E-glass and polyester/E-glass pultruded T-section members and the flexural buckling of vinylester/E-glass pultruded H-section members are used as numerical examples. The comparison of the analytical results to the experimental and FE analysis results reveals that the proposed buckling equations predict the buckling loads of pultruded members conservatively by about 7%.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.17-24
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• 2002

인발성형 적층 FRP 복합소재의 재료상수는 일반적으로 시편실험을 통해 구해지고 있으나, 본 논문에서는, 실험에서 구한 탄성계수가 부재일 경우를 위해, Micromechanics와 Classical Laminate Theory (CLT)를 이용한 적층 FRP 복합재료의 탄성계수(E/sub L/과 E/sup b//sub L/) 예측모델을 제시하였다 또한 예측모델로부터 구한 값과 실험으로부터 얻은 실측값을 비교하여 그 적정성을 검증하였고, 예측모델의 민감도 및 확률적인 특성을 구성소재 (Constituents)의 재료특성에 근거해 평가하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.4 s.70
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• pp.427-434
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• 2005

In this study, to develop composite bridge deck of many advantages such as light weight, high strength, corrosion resistance and high durability, profile design, laminate design and finite element analysis were carried out. In the analysis, 5-girder single span bridge with composite deck was considered. Deflection serviceability, failure criteria and web buckling were evaluated. Composite deck of designed profile was fabricated with pultrusion process. The coupon tests were conducted for the fabricated deck and the results were described.

• Journal of the korean Society of Automotive Engineers
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• v.18 no.5
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• pp.96-120
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• 1996

현재 자동차용 복합재료를 생산하는데 유리한 제조방법으로는 압축성형 (Compression Molding), 액상성형(Liquid Molding), 인발성형(Pultrusion), 필라멘트 와인딩성형(Filament Winding)등이 있다. 압축성형은 현재 자동차 외장부품 성형에 널리 알려져 있는 SMC(Sheet Molding Compound)성형, 최근에 많은 연구가 되고 있는 LMPC(Low Pressure Molding Compound)성형, GMT(Glass Mat Reinforced Thermoplastics)성형 등이 있다. 액상성형은 RTM(Resin Transfer Molding)과 VARI (Vacuum Assisted Injection Molding), SRIM(Structure Reaction Injection Molding) 등이 있으며, 자동차 산업뿐만 아니라 일반 산업에서도 최근 많은 각광을 받고 있다. 그러므로 본 소고에서는 자동차용 복합재료의 제조에 널리 사용되는 성형공정에 대하여 간단히 살펴보고, 자동차 부품에 있어서의 복합재료 응용 현장과 최근 환경문제가 대두되면서 관심의 초점이 되고 있는 자동차용 복합재료 재활용 기술에 대하여 고찰하고자 한다.

• Journal of the Korean Society of Mechanical Technology
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• v.20 no.6
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• pp.796-802
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• 2018

In order to remove rust and impurities from surface of raw SUS circular bar, peeling machine is used to make lustrous and clean surface of SUS circular bar. Drawing process system is used to manufacture SUS hexagonal bar. SUS hexagonal bar have been widely used to make hexagonal bolt/nut, adapter and fittings and so on. The purpose of this study is to investigate the stabilities for guide bar of clamp in drawing process system. As the results, the guide bar showed structural stability in cases of below load of 50 Ton and over hook radius of 3.0mm. Further as the thickness of guide bar hooking with jaw was increased, minimum safety factor was decreased.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.1A
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• pp.99-106
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• 2006

Due to single symmetry of cross section, T-shaped members are likely to buckle in a flexural-torsional mode when they are subjected to axial compression. Therefore, the flexural-torsional buckling can be regarded as a governing mode of global buckling. An experimental program has been carried out to investigate the flexural-torsional buckling behavior of pultruded T-shaped members. Two types of pultruded members were tested in the experiment, and they were made of either E-glass/vinylester or E-glass/polyester. Lay-up and thickness of reinforcing layers, volume fractions of each constituents in layers, mechanical properties were experimentally determined. Two sets of knife edge fixure were used to simulate simple support condition for flexure and twisting, and the lateral displacements and the angle of twist were measured using three potentiometers. Every specimen buckled in a flexural-torsional mode, and most of the specimens showed post-buckling strength.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.11
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• pp.9-16
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• 2021

As the climate changes rapidly due to warming, it is becoming very important to ensure the stability of environmental structures. It is necessary to choose a material that withstands repeated external forces (wind loads) and satisfies members and joints that have energy absorbing power. Even if the strength of the traffic light attachment is sufficient, if the rigidity is insufficient, there is a limit to the displacement during strong winds. Excessive deformation may cause damage and fall, resulting in a safety accident. The author intends to study mechanical properties and resistance to external environment as a structural material capable of withstanding wind load (50m/sec) by fabricating a C/GFRP composite traffic light attachment using the pultrusion method (Pultrusion).

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.2
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• pp.191-200
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• 2005

To develop composite bridge deck, comparative study on the flexural characteristics of deck fabricated with filament winding and pultrusion was performed. In this study, composite deck of triangular shape was fabricated with filament winding process and flexural tests were conducted along with pultruded 'Duraspan' deck. Failure load, maximum deflection and strains were compared with each other. Also finite element analysis for filament winding deck was carried out and the results were compared with those from experiments.

• Proceedings of the CALSEC Conference
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• 2001.08a
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• pp.105-109
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• 2001

성형의 종류 ◈금속 성형 ㆍ 스탬핑(Stamping) ㆍ 정밀 블랭킹(Fine Blanking) ㆍ 딥 드로잉(Deep Drawing) ㆍ 다이캐스팅(Die Casting) ㆍ 인베스트먼트 주조(Investment Casting) ㆍ 분말 야금(Power Metallurgy) ㆍ 인발(Wire Drawing) ㆍ 압출(Extrusion) ㆍ 단조(Forging) ㆍ ㆍ코이닝(Coining) ㆍ... ◈비금속 성형 ㆍ 사출(Injection) ㆍ 압축(Compression) ㆍ 블로우 성형(Blow Molding) ㆍ 진공 성형(Vacuum Molding) ㆍ 발포 성형(Foam Molding) ㆍ 피복(Encapsulation) ㆍ 회전식(Rotational) ㆍ 주조(Casting) ㆍ 적층(Laminating) ㆍ 압출(Extrusion) ㆍ...(중략)