• 한국건축시공학회지
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• 제15권6호
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• pp.615-620
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• 2015

고성능 시멘트 복합재료(HPFRCC)는 인장력 작용 하에 있어서 초기 균열이 발생한 이후에도 변형의 증가와 함께 응력이 증가하는 변형경화 특성과 다수의 미세 균열이 발생함으로써 균열 폭 제어 특성을 나타낸다. 그러나 국내의 HPFRCC의 연구는 단일섬유를 중심으로한 제조방법이나 경화전후의 재료적 성상에 관한 연구들이 진행되어지고 있으나 복합섬유인 HPFRCC를 실무에서 활용하기 위한 연구는 미미한 실정이다. 따라서 본 연구에서는 시공성 및 경제성을 고려하여 실무에서 효율적인 활용성을 검토하기 위한 방안으로 강섬유(이하 SL)와 유기섬유(이하 OL)를 조합한 복합섬유로 유동성 및 강도 등 제반 공학적 특성을 검토하고자 한다. 결과적으로 강섬유 장섬유(SL)과 유기섬유 장섬유(OL)의 복합섬유를 활용하는 HPFRCC의 제반 공학적 성능을 검토한 결과 복합섬유 혼입율 1.5%일 때 가장 우수한 것으로 판단되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.88-89
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• 2017

Due to the increase in the usage of explosive materials and terrorism, the interest towards the superior explosion protective HPFRCC has risen. In existing research, the optimum ratio for solving the problematic problems such as the optimum fiber incorporation rate and the self-shrinkage crack of HPFRCC had been derived. However, there had been few or even no research upon how effective HPFRCC would perform protective explosion-proof in actual explosion. Therefore, this research compared the explosion-proof performance of HPFRCC according to fiber commination and mixing ratio. As a result, the combination of steel fiber and organic fiber showed excellent flow and strength, and it also improved the explosion resistance.

• Computers and Concrete
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• 제16권4호
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• pp.545-568
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• 2015

High Performance Fiber Reinforced Cementitious Composites which are called HPFRCC, include cement matrices with strain hardening response under tension loading. In these composites, the cement mortar with fine aggregates, is reinforced by continuous or random distributed fibers and could be used for various applications including structural fuses and retrofitting of reinforced concrete members etc. In this paper, mechanical properties of HPFRCC materials are reviewed briefly. Moreover, a reinforced concrete beam (experimentally tested by Maalej et al.) is chosen and in different specimens, lower or upper or both parts of that beam are replaced with HPFRCC layers. After modeling of specimens in ABAQUS and calibration of those, mechanical properties of these specimens are investigated with different thicknesses, tensile strengths, tensile strains and compressive bars. Analytical results which are obtained by nonlinear finite analyses show that using HPFRCC layers with different parameters, increase loading capacity and ultimate displacement of these beams compare to RC specimens.

• 한국건축시공학회지
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• 제17권1호
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• pp.1-8
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• 2017

최근 전 세계적으로 폭탄테러 및 폭발사고가 빈발하여, 인명 및 재산피해가 증가하고 있다. 따라서 방호 방폭 성능을 갖는 고성능 시멘트 복합재료(HPFRCC)에 대한 관심이 증가하고 있다. 이에 본 연구에서는 최적의 HPFRCC를 군부대 시설에 실제적으로 적용하기에 앞서 유 무기 복합섬유 혼입율 및 ERCO 혼입율 변화에 따른 HPFRCC의 기초적 특성 및 자기수축 저감 성능을 분석하고자 하였다. 그 결과, 적절한 유동성, 강도, 자기수축저감 효과를 종합적으로 고려할 때 복합섬유(SS+OL) 혼입율 1.5%에 ERCO 0.5%의 혼입이 가장 효과적인 것으로 평가 되었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2016년도 춘계 학술논문 발표대회
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• pp.30-31
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• 2016

As the treatments of many kinds of explosive objects increase recently, it is in the trend that explosion accidents increase. Thus, many studies on HPFRCC (High-performance Fiber-reinforced Cement Composites) whose ductility is enhanced are being conducted actively in order to minimize the damages from explosion accidents. However, HPFRCC, the self-shrinkage of HPFRCC is on the rise as a problem since it becomes ultra-high strengthened by using low W/B. Thus, in this study, it is intended to evaluate the capacity for reducing the self-shrinkage of HPFRCC depending on some changes of ERCO(Emulsified Refined Cooking Oil) replacement ratio and the fiber replacement ratio between some short steel fibers (SS) and some long organic fibers (OL). As a result, it was found that some excellent effects are exerted since the self-shrinkage was reduced a lot as the ERCO replacement ratio increases and the fiber replacement ratio of SS rather than OL increases.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.369-372
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• 2006

In this paper, analysis method of HPFRCC is proposed as predicting properties flexural behavior. For analyzing HPFRCC beam, properties of strain-hardening, multiple cracking, and crack spacing control are considered as non-homogeneous material properties of the beam. This paper focused on the deflection, maximum moment of the flexural beam, distribution of crack width with the monte carlo simulation.

• 한국구조물진단유지관리공학회 논문집
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• 제18권5호
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• pp.34-40
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• 2014

HPFRCC는 물-결합재비 (W/B)가 20%로 상당히 낮고 굵은 골재를 사용하지 않으며, 고분말 혼화재료를 혼입하기 때문에 자기수축이 상당히 크게 발생하여 구조물 적용 시 균열저감대책이 필요하다. 따라서 이 연구에서는 HPFRCC의 수축을 효율적으로 저감시키기 위한 방법으로 수축저감제와 팽창재의 사용을 검토하기 위하여 이들의 단독 또는 병행 혼입률에 따른 역학적 특성과 구속 수축특성을 평가하였다. 구속수축 실험 중에서 링-테스트 (Ring-test)를 통하여 HPFRCC에 사용되는 시멘트에 대하여 중량비로 수축저감제 1%와 팽창재를 7.5%를 병행 사용하였을 경우 압축강도와 인장강도가 크게 저하되지 않으면서도 수축을 가장 효율적으로 저감시킬 수 있는 최적 배합임을 도출하였고 수정된 건조수축 균열실험을 통하여 이를 검증하였다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.59-62
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• 2003

Kinds, shapes and fraction ratios of fibers have influence on properties of HPFRCC(High-Performance Fiver Reinforced Cementitious Concrete ) like bending strength, strain capacity and fracture toughness. For example, hydrophilic fibers have different chemical bond strength from hydrophobic fibers, fiber shapes influence on fiber pull-out and rupture, and fiber volume fraction influence on bending strength. In this study, to estimate influences of kinds, shapes and fraction ratios of fibers, we make HFRCC with 3 kind of fiber in various volume fraction of fiber and compare cracking, bending strength and fracture toughness. As the results, bending strength of HPFRCC was increased as fiber volume fraction was Increase and fiber tensile strength was increase, and strain capacity and fracture toughness of HFRCC was higher in fiber pull-out fracture than in fiber rupture fracture. And HFRCC showing pseudo strain hardening has higher fiber reinforce efficiency than others.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.69-70
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• 2015

This study has attempted to derived an optimum fiber replacing ratio for practical use by measuring tensile strength and length deformation followed by variation of fiber replacing ratio among the basic characteristics of HPFRCC in order to evaluate the possibility of practical use of HPFRCC. As a result of performing experiment and research, the optimum replacement ratio was determined at the fiber replacing ratio of 1.5% when compressive strength, tensile strength and tensile stress-strain curve.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.152-153
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• 2014

Recently, there are many research for increasing tensile strength of concrete using fiber-reinforced mortar. Especially, the research about the high ductile concrete with fiber-reinforcement which behaves strain-hardening (defined as HPFRCC) is performed while it has the drawback of decreasing workability because of interruption of fibers such as fiber-ball effect. Hence to solve this problem, as a previous research, combination of metal fiber and organic fiber was suggested. Although this research achieved favorable result of workability of HPFRCC, the research scope was concentrated on workability of the mortar. Therefore, in this research, based on the fiber-combination of previous research, the tensile properties is evaluated depending on water-to-binder ratios to obtain improved tensile performance.