• 제목/요약/키워드: polyamide fiber

검색결과 108건 처리시간 0.022초

철도 터널 구조물 시공을 위한 다발형 폴리아미드섬유 보강 숏크리트 (Multiple Polyamide Fiber Reinforced Shotcrete for Railway Tunnel Structure)

  • 전중규;정재민;윤지현;전찬기
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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    • pp.1214-1219
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    • 2011
  • Fiber reinforced shotcrete began to be used in tunnel constructions because it facilitates and expedites the construction process, and improves reinforcement properties. As one of the most widely used forms of shotcrete used in tunneling, steel fiber reinforced shotcrete offers excellent strength and ductility and allows quick reinforcement. However, steel fibers tend to lump together in cement matrix, and low levels of water and acid resistance cause corrosion in steel fiber, resulting in cracks and delamination. In particular, rebound and backlash of steel fiber is significantly increased during steel fiber reinforced shotcrete construction, compromising the flexural toughness and quality of shotcrete. In order to resolve the problems associated with steel fiber reinforced shotcrete and improve the application, durability, and cost-effectiveness of shotcrete, this paper proposes methods for manufacturing and constructing tunnels with multiple polyamide fiber reinforced shotcrete. We performed experiments to evaluate the performance of the proposed shotcrete, and the experimental results indicate that the multiple polyamide fiber reinforced shotcrete proposed in this paper offers outstanding performance that meets various construction design criteria.

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보강섬유의 종류에 따른 섬유보강 콘크리트의 휨특성 (Flexural Behavior of Fiber-Reinforced Concrete by Fiber Types)

  • 강영태;김규용;이보경;이상규;김경태;남정수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 추계 학술논문 발표대회
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    • pp.15-16
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    • 2017
  • In this study, the flexural behavior of fiber-reinforced concrete by fiber type were evaluated. As a result, the flexural strength of the hooked steel fiber-reinforced concrete(HSFRC) was lower than that of the amorphous metallic fiber reinforced concrete(AFRC), however it was shown strain-softening behavior by the pull-out of fiber. The flexural strength and the equivalent flexural strength of polyamide fiber-reinforced concrete(PAFRC) were lower than other specimens, but the equivalent flexural strength ratio was similar to that of AFRC. The flexural behavior of the fiber-reinforced concrete was associated with the bonding and pull-out properties of the fiber and matrix depending on the fiber type.

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다발형 폴리아미드섬유 보강 콘크리트의 휨거동에 관한 실험적 연구 (A Experimental Study on the Flexural Behavior of Bundle Type Polyamide Fiber Reinforced Concrete)

  • Jeon, Chan Ki;Jeon, Joong Kyu
    • 한국재난정보학회 논문집
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    • 제10권1호
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    • pp.61-70
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    • 2014
  • 일반적으로 건설재료 용도로 많이 사용되고 있는 유기섬유 보강 콘크리트는 섬유 자체의 인장강도 및 탄성계수는 낮지만, 휨거동, 균열에 대한 저항성 및 충격저항성 등의 특성은 우수하며, 내화학성이 뛰어나고 부식의 우려가 없는 것으로 널리 알려져 있다. 최근 해외에서는 유기섬유 보강재를 터널 숏크리트와 프리캐스트 세그먼트 라이닝, 교량 슬래브 및 PC제품 분야에서 일부 활용되고 있으며, 그 종류 또한 다양하다. 본 연구에서는 다발형 폴리아미드섬유를 혼입한 콘크리트의 휨거동 특성을 ASTM C 1609 및 KS F 2566에 준하여 하중-처짐 관계를 도출하여 유기섬유 보강 콘크리트의 적용 가능성을 검토하였다.

Polymide 6에서 Cyclic Diphosphonate Ester와 Melamine의 난연 효과 (Flame Retardant Synergistic Performance between Cyclic Diphosphonate Ester and Melamine in Polyamide 6)

  • Wang, Xueli;Jiang, Jianming;Yang, Shenglin;Jin, Junhong;Li, Guang
    • 폴리머
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    • 제32권2호
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    • pp.125-130
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    • 2008
  • A commercial cyclic diphosphonate ester (TPMP) and melamine (MA) was combined and added to polyamide 6 (PA6) to prepare the fire retardant PA6. An increase of the oxygen index to 28.6 as well as an improvement of the UL-94 classification to V-0 rating was observed. Cone measurements explained the rate of heat release (RHR) decreased and TGA showed the early decomposition and high solid residue due to co-addition of TPMP and MA, suggesting the occurrence of synergistic effect of TPMP and MA on fire resistance of PA6. The morphology of the char developed during combust ion showed the appearance of thick, intumescent cells on the surface of retardant PA6, which protects the underlying material from the action of the heat flux or flame and limits the diffusion of combustible volatile products towards the flame and oxygen.