• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.169-172
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• 2005

Recently the repair of damaged reinforced concrete members by the external bonding of fiber-reinforced polymer laminates has received considerable attention. This paper investigates the flexural behaviors of beam strengthened with Aramid fiber sheets(AFS), and attempts to evaluate the flexural strength of such RC beams by the use of nonlinear flexural analysis because the application of the KCI strength method to strengthened beam is somewhat limited and the failure strain of AFS is overestimated in particular cases.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.99-100
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• 2009

우리나라 학교건물의 상당수는 내진기준이 제정되기 전에 건립되었으며, 간막이벽으로 채광 및 환기 등을 고려하여 조적허리벽을 사용하고 있다. 기존 연구에 따르면 이러한 조적허리벽은 지진 발생시 기둥의 유효높이를 줄여주게 되어 단주효과로 인한 취성파괴를 유발 시킬 수 있다. 따라서 본 연구에서는 전단강도와 연성능력 향상의 효과가 있을 것으로 예상되는 아라미드 섬유를 사용하여 보강한 기둥 및 조적 허리벽의 내진성능향상 검증을 위한 실험을 수행 하고자 한다.

• 한국염색가공학회지
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• 제15권2호
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• pp.93-101
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• 2003

To acquire dyeing ability on aramid(Nomex) spun yarn in supercritical fluid dyeing, supercritical fluid dying(SFD) machine of 3L scale was designed. C. I. Disperse Red 60 and Red 360 were used in this work. It was possible to increase dyeing ability and to get level dyeing of fiber by attaching assistance devices(controlling device of supercritical fluid, nozzle, cover of carrier, etc.) to SFD machine. Physical properties(tensile strength, elongation, shrinkage) of Nomex spun yam treated by SFD were not changed. K/S values of dyed Nomex spun yam with Red 360 were higher than that with Red 60 and color fastness of dyed Nomex spun yam by SFD was similar to that by conventional dyeing method.

• 대한기계학회논문집A
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• 제24권7호
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• pp.1810-1816
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• 2000

A hybrid composite APAL(Aramid Patched Aluminum alloy) , consisting of Al 2024-T3 aluminum alloy plate sandwiched between two aramid/epoxy laminates, was developed. The characteristics of tensile s trength were investigated and statistical properties of tensile strength were studied in terms of Weibull distribution probability with number of AFRP laminates. The tensile strength of APAL was inproportional to number of AFRP laminates and followed the two-parametic Weibull distribution.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 춘계학술대회 논문요약집
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• pp.74-74
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• 2004

탄소섬유강화 적층재(Carbon Fiber Reinforced Plastic, 이하 CFRP)는 강성도는 뛰어나지만 충격특성에는 취약한 단점이 있다. 따라서 충격저항과 충격에너지 흡수율이 상대적으로 우수한 유리섬유강화 적층재(Glass Fiber Reinforced Plastic, GFRP) 및 아라미드섬유강화 적층재(Aramid Fbier Reinforced Plastic, 이하 AFRP)를 CFRP 적용분야에 대체하고 점차적으로 피로특성을 개선시켜 나간다면 특성이 더욱 개선된 제품을 사용할 수 있을 것으로 판단된다.(중략)

• 한국농공학회지
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• 제45권2호
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• pp.58-67
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• 2003

Over the last decade fiber-reinforced polymer (FRP) reinforcement consisting of glass, carbon, or aramid fibers embedded in a resin such as vinyl ester, epoxy, or polyester has emerged as one of the most promising and affordable solutions to the corrosion problems of steel reinforcement in structural concrete. But reinforcing rebar for concrete made of FRP rebar has linear elastic behavior up to tensile failure. For safety a certain plastic strain and an elongation greater than 3% at maximum load is usually required for steel reinforcement in concrete structures. The same should be required for FRP rebar. Thus, the main object of this study was to develop new type of hybrid FRP rebar Also, this study was evaluated to the mechanical properties of Hybrid FRP rebar. The Manufacture of the hybrid FRP rebar was achieved by pultrusion, and braiding and filament winding techniques. Tensile and interlaminar shear test results of Hybrid FRP rebar can provide its excellent tensile strength-strain behavior and interlaminar stress-strain behavior.

• Steel and Composite Structures
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• 제11권6호
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• pp.455-468
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• 2011

Although retrofitting and strengthening reinforced concrete (RC) columns by wrapping fiber reinforced polymer (FRP) composites have become a popular technique in civil engineering, the study on reinforced high-strength concrete (HSC) columns is still not sufficient. The objective of these companion papers is to investigate the mechanical properties of reinforced HSC square columns confined by aramid FRP (AFRP) jackets under concentric compressive loading. In the part I of these companion papers, an experiment was conducted on 54 confined RC specimens and nine unconfined plain specimens, the considered parameters were the concrete strength, the thickness of AFRP jackets, and the form of AFRP wrapping. The experimental process and results are presented in detail. Subsequently, some discussions on the confinement effect, failure modes, strength, and ductility of the columns are carried out.

• Steel and Composite Structures
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• 제11권4호
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• pp.325-340
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• 2011

Based on the experimental data presented in part I of these companion papers, a semi-empirical model is proposed for axial stress-strain curves of reinforced high-strength concrete square columns confined by aramid fiber reinforced polymer (FRP) jackets. Additionally, a three-dimensional finite element model is developed to simulate the mechanical behaviors of the columns. In the finite element model, both material nonlinear and contact nonlinear are taken into account. Moreover, the influence of contact nonlinear (i.e., the end friction on the contact surface between test machines and specimens) is investigated deeply. Predictions from both the semi-empirical model and the finite element model agree with the experimental results, and it is also demonstrated that the friction coefficient of end friction notably affect the properties of columns when it ranges from 0.00 to 0.25.

• 한국해양공학회지
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• 제11권3호
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• pp.69-75
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• 1997

A A12024-T3 plate has been reinforced with AFRP to be a Hybrid-Composite, APAL. The fatigue life of the APAL has been investigated. The effects of bonding surface, numbers of AFRP bonded and AFRP orientation on fatigue life have been compared with A12024-T3 plate. Fatigue life of APAL has been remarkedly increased compared with that of A12024-T3 plate. The fatigue life has depended on bonding surface and AFRP orientation, but no relationship could be found with numbers of AFRP laminates.

• 한국구조물진단유지관리공학회 논문집
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• 제1권1호
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• pp.65-73
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• 1997

In this paper, It is the effect of using fiber sheet (Carbon Fiber Sheet & Aramid Fiber Sheet) and Steel Plate for reinforced concrete beam. 25 specimens are tested, 16 specimens are for bending capacity and the other are for shear capacity. In the case of bending testing, the kind and quantity of the reinforcement materials, the bondage and the existence of crack were selected as experimental variables. In the case of shear testing, It is testified the effect of reinforcement with the variables of the method of reinforcement (side type and U type). As a result, Using the reinforcing materials can increase the capacity of bending and shear stress.