• Title/Summary/Keyword: HPFRCC

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Field Application of Land Mine Crater using HPFRCC and ERCO (HPFRCC 및 ERCO를 활용한 지뢰매설호 현장적용)

  • Lee, Jea-Hyeon;Lee, Jong-Tae;Jung, Ung-Seon;Jo, Sung-Jun;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2017.05a
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    • pp.90-91
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    • 2017
  • Military camps deal with various types of explosives. For instance, military engineering unit conducts education and training for laying landmines. However, in case of land mine craters installed with regular-level RC, structural safety may be in danger thus there is a necessity to utilize High Performance Fiber-Reinforced Cement Composites (HPFRCC), which has high functionality in protection and blast resistance. Therefore, in this research we conducted an field application of land mine crater of HPFRCC, using the existing optimal fiber mixing ratio and ERCO addition ratio.

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Impact Resistance Characteristics of HPFRCC Depending on Various Fiber Replacing Ratio (섬유혼입율 변화에 따른 HPFRCC의 내충격 특성)

  • Park, Yong-Jun;Kim, Dae-Gun;Mun, Gyeong-Sik;Han, Sang-Hyu;Kim, Gyu-Yong;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2015.05a
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    • pp.75-76
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    • 2015
  • This study has examined the impact resistance and blast resistance characteristics of HPFRCC as a research on impact resistance and blast resistance characteristics using high volume mortar and high velocity projectile for evaluating the protection performance of actual buildings as small quantity experiment of laboratory conditions is performed although there was an instance of performing research on mortar that has reinforced fiber followed by the rise of problems on the damage of human life and buildings created due to explosion and shock. As a result, the destruction loss area and depth have decreased in case of the surface compared to the rear side. As tensile strength and tenacity have increased with the increased fiber replacing ratio, a tendency of destruction loss area and depth getting decreased was shown as the impact resistance has increased.

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Workability evaluation of HPFRCC depending on mixing proportions (배합비 변화에 따른 HPFRCC의 유동성 평가)

  • Park, Jae-Yong;Kang, Byeong-Hoe;Park, Yong-Jun;Han, Dong-Yeop;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2014.11a
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    • pp.150-151
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    • 2014
  • Although there has been many research regarding improving anti-shock performance and durability of concrete using fiber-reinforcement, there are still drawback on workability with interruption of fibers such as fiber-ball. Hence to solve this problem, in previous research, the optimum combination of fibers to improve workability of HPFRCC. In this research, based on the result of previous research, to improve the workability further, various fine aggregate contents is evaluated on workability, and the most appropriate mixing proportion is suggested.

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Tension Stiffening of High Performance Fiber-Reinforced Cementitious Composites (고인성 섬유보강 시멘트 복합체의 인장강성)

  • Yun Hyun-Do;Yang Il-Seung;Han Byung-Chan;Hiroshi Fukuyama;Cheon Esther;Kim Sun-Woo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2004.11a
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    • pp.441-444
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    • 2004
  • This paper presnets the tensile behavior of 8 high performance fiber-reinforced cementitious composites (HPFRCCs) members, each reinforced with one deformed bar 16mm in diameter. The variables included HPFRCC(Ductal, steel cord and polyethylene hybrid fiber, PE fiber) versus normal concrete. Fibers used in HPFRCC significantly increased tensile strength, ductility, and tension stiffening of cementitious materials. For HPFRCC, after first cracking, tensile load continue to rise without fracture localization. Sequentially developed parallel cracks contributed to the inelastic strain at increasing stress level. After yielding of the reinforcing bars, HPFRCC showed increases in loads with increasing strains.

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A Study on the Rheology Properties for Development of Sprayed High Performance Fiber Reinforced Cementitious Composites for Protection and Blast Resistant (방호·방폭용 뿜칠형 고성능 섬유보강 시멘트 복합재료 개발을 위한 레올로지 특성 연구)

  • Choi, Yun-Wang;Choi, Byung-Keol;Park, Man-Seok;Sung, Don
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.2 no.3
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    • pp.188-195
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    • 2014
  • This paper was evaluated the rheology properties according to each step of paste, mortar and HPFRCC as a part of the basic study to development of sprayed high performance fiber reinforced cementitious composites(HPFRCC) for protection and blast resistant. Rheology test results in step of paste, in case of GGBFs and FA, it showed that the plastic viscosity and yield stress reduced gradually according to the increase of mixing rate, and in case of SF, the plastic viscosity and yield stress increased radically starting from the mixing rate of 10%. Rheology test results in step of mortar, type of aggregates, it showed that particle shape and grading of aggregate is influence on plastic viscosity and yield stress, and change of volume ratio is influence on plastic viscosity than yield stress. Fluidity and rheology test results in step of HPFRCC, if after a fiber mixed, it showed that viscosity agent is more effective to improve the fluidity and fiber dispersion than superplasticizer.

Cyclic Behavior of High-Performance Fiber-Reinforced Cement Composite Coupling Beam Having Diagonal Reinforcement (대각철근을 갖는 고성능 섬유보강 시멘트 복합체 연결보의 이력거동 평가)

  • Kwon, Hyun-Wook;Jeon, Yong-Ryul;Lee, Ki-Hak;Shin, Myung-Su;Han, Sang-Whan
    • Journal of the Korea Concrete Institute
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    • v.25 no.6
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    • pp.649-656
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    • 2013
  • Coupled shear walls can provide an efficient structural system to resist lateral force. However, the reinforcement detail for diagonally reinforced coupling beams required by ACI-318 often causes the difficulties in construction due to the reinforcement congestion and interference among reinforcement. This paper is to evaluate cyclic behavior of High-Performance Fiber-Reinforced Cement Composite (HPFRCC) coupling beams having reduced transverse reinforcement around the beam perimeter. Experimental test was conducted using three specimens having a beam aspect ratio 2.0. Test results showed that HPFRCC coupling beams with half of transverse reinforcement required by ACI-318 provided similar energy dissipation capacities compared with the coupling beams having reinforcement satisfy the requirement of ACI-318.

Effect of Hybrid Fibers on the Engineering Properties of HPFRCC (섬유 조합변화가 HPFRCC의 공학적 특성에 미치는 영향)

  • Han, Dongyeop;Han, Min Gheol;Kang, Byeong Hoe;Park, Yong Jun
    • Journal of the Korea Institute of Building Construction
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    • v.14 no.6
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    • pp.639-645
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    • 2014
  • For the construction materials, concrete, as the most widely used material, is focused on its improvement of performance. Although concrete has many advantages of easiness of handling, economical benefits, and high compressive strength, low tensile strength, brittleness and drying shrinkage are reported as the drawbacks of concrete. Hence, to solve these drawbacks of concrete, many research has conducted especially using fiber-reinforced concrete technology. Especially, HPFRCC which has high volume of fiber reinforcement was suggested as a solution of these drawbacks of normal concrete with increased ductility while it has the possibility of workability loss with fiber clumping which can cause low performance of concrete. Therefore, in this paper, optimized fiber combination with either or both metal and organic fibers is suggested to provide better performance of HPFRCC in tensile strength and ductility. As the results of experiment, better workability was achieved with 1 % of single fiber rather than multiple fibers combinations, espeically, short steel fiber showed the best workability result. Furthermore, in the case of organic fibers which showed higher air content than steel fibers, higher compressive strength was achieved while lower tensile and flexural strength were shown.

Assessment of the Damage in High Performance Fiber-Reinforced Cement Composite under Compressive Loading Using Acoustic Emission (AE기법에 의한 압축력을 받는 고인성 섬유보강 시멘트 복합체의 손상 평가)

  • Kim, Sun-Woo;Yun, Hyun-Do
    • Journal of the Korea Concrete Institute
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    • v.21 no.5
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    • pp.589-597
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    • 2009
  • High Performance Fiber-reinforced Cement Composite (HPFRCC) shows the multiple crack and damage tolerance capacity due to the interfacial bonding of the fibers to the cement matrix. For practical application, it is needed to investigate the fractural behavior of HPFRCC and understand the micro-mechanism of cement matrix with reinforcing fiber. This study is devoted to the investigation of the AE signals in HPFRCC under monotonic and cyclic uniaxial compressive loading, and total four series were tested. The major experimental parameters include the type and volume fraction of fiber (PE, PVA, SC), the hybrid type and loading pattern. The test results showed that the damage progress by compressive behavior of the HPFRCC is a characteristic for the hybrid fiber type and volume fraction. It is found from acoustic emission (AE) parameter value, that the second and third compressive load cycles resulted in successive decrease of the amplitude as compared with the first compressive load cycle. Also, the AE Kaiser effect existed in HPFRCC specimens up to 80% of its ultimate strength. These observations suggested that the AE Kaiser effect has good potential to be used as a new tool to monitor the loading history of HPFRCC.

An Experimental Study on the Mechanical Properties of HPFRCCs Reinforced with the Micro and Macro Fibers (마이크로 및 매크로 섬유에 의해 보강된 고인성 시멘트 복합재료의 역학적 특성에 관한 실험적 연구)

  • Kim Moo-Han;Kim Jae-Hwan;Kim Yong-Ro;Kim Young-Duck
    • Journal of the Korea Concrete Institute
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    • v.17 no.2 s.86
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    • pp.263-271
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    • 2005
  • HPFRCC(High Performance Fiber Reinforced Cementitious Composite) is a class of FRCCs(Fiber Reinforced Cementitious Composites) that exhibit multiple cracking. Multiple cracking leads to improvement in properties such as ductility, toughness, fracture energy, strain hardening, strain capacity, and deformation capacity under tension, compression, and bending. These improved properties of HPFRCCs have triggered unique and versatile structural applications, including damage reduction, damage tolerance, energy absorption, crack distribution, deformation compatibility, and delamination resistance. These mechanical properties of HPFRCCs become different from the kinds and shapes of used fiber, and it is known that the effective size of fiber in macro crack is different from that in micro crack. This paper reports an experimental findings on the mechanical properties of HPFRCCs reinforced with the micro fiber(PP50, PVA100 and PVA200) and macro fiber(PVA660, SF500). Uniaxial compressive tests and three point bending tests are carried out in order to compare with the mechanical properties of HPFRCCs reinforced with micro fibers or hybrid fibers such as compressive strength, ultimate bending stress, toughness, deformation capacity and crack pattern under bending, etc.,