• 제목/요약/키워드: Steel Fiber Reinforced Concrete (SFRC)

검색결과 169건 처리시간 0.025초

Cyclic performance of steel fiber-reinforced concrete exterior beam-column joints

  • Oinam, Romanbabu M.;Kumar, P.C. Ashwin;Sahoo, Dipti R.
    • Earthquakes and Structures
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    • 제16권5호
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    • pp.533-546
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    • 2019
  • This study presents an experimental investigation on six beam-column joint specimens under the lateral cyclic loading. The aim was to explore the effectiveness of steel fiber-reinforced concrete (SFRC) in reducing the transverse shear stirrups in beam-column joints of the reinforced concrete (RC) frames with strong-columns and weak-beams. Two RC and four SFRC specimens with different types of reinforcement detailing and steel fibers of volume fraction in the range of 0.75-1.5% were tested under gradually increasing cyclic displacements. The main parameters investigated were lateral load-resisting capacity, hysteresis response, energy dissipation capacity, stiffness degradation, viscous damping variation, and mode of failure. Test results showed that the diagonally bent configuration of beam longitudinal bars in the beam-column joints resulted in the shear failure at the joint region against the flexural failure of beams having straight bar configurations. However, all SFRC specimens exhibited similar lateral strength, energy dissipation potential and mode of failure even in the absence of transverse steel in the beam-column joints. Finally, a methodology has been proposed to compute the shear strength of SFRC beam-column joints under the lateral loading condition.

Prediction of elastic modulus of steel-fiber reinforced concrete (SFRC) using fuzzy logic

  • Gencoglu, Mustafa;Uygunoglu, Tayfun;Demir, Fuat;Guler, Kadir
    • Computers and Concrete
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    • 제9권5호
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    • pp.389-402
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    • 2012
  • In this study, the modulus of elasticity of low, normal and high strength steel fiber reinforced concrete has been predicted by developing a fuzzy logic model. The fuzzy models were formed as simple rules using only linguistic variables. A fuzzy logic algorithm was devised for estimating the elastic modulus of SFRC from compressive strength. Fibers used in all of the mixes were made of steel, and they were in different volume fractions and aspect ratios. Fiber volume fractions of the concrete mixtures have changed between 0.25%-6%. The results of the proposed approach in this study were compared with the results of equations in standards and codes for elastic modulus of SFRC. Error estimation was also carried out for each approach. In the study, the lowest error deviation was obtained in proposed fuzzy logic approach. The fuzzy logic approach was rather useful to quickly and easily predict the elastic modulus of SFRC.

강섬유 보강 콘크리트 구조물의 해석을 위한 K&C모델의 보정 (Modified K&C Model for Numerical Analysis of Steel-Fiber-Reinforced Concrete Structure)

  • 박강규;이민주
    • 한국전산구조공학회논문집
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    • 제34권2호
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    • pp.85-91
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    • 2021
  • 본 연구에서는 섬유보강콘크리트(SFRC) 구조물의 수치해석을 위한 K&C모델의 보정기법을 소개하였다. SFRC 1축 및 3축 압축강도 실험결과를 기반으로 보정을 수행하였으며, 단일요소 해석결과를 실험결과와 비교함으로써 보정 기법의 검증을 수행하였다. 또한, 변형률 속도의 영향을 반형하기 위해 동적증가계수(DIF)를 고려하여 SFRC 구조물의 발사체 관통해석을 수행함으로써 보정기법의 적용 가능성을 확인하였다.

철근콘크리트 및 강섬유철근콘크리트보의 동적거동 (Dynamic behavior of RC and SFRC Beams)

  • 강보순;황성춘;심형섭
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.662-667
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    • 2001
  • In this paper, damping behavior of steel fiber reinforced concrete(SFRC) beams by experimental and numerical method is discussed. Because of its improved ability to dissipate energy, SFRC has a better damping behavior than that of reinforced concrete(RC). Damping behavior is influenced by longitudinal reinforcement ratio, volume and type of steel fiber, strength of concrete and the stress level. Damping in the SFRC beams has been evaluated from dynamic experimental test data at various levels of cracked states in the beams. A FEM program(TICAL) has been developed based on the relationships between curvature and damping. It is observed for SFRC beams with 0.44% of tensile reinforcement steel that approximate 5% to 35% was relatively increased in the damping ratio generally depending on the load level.

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철근콘크리트 및 강섬유 철근콘크리트보의 에너지감쇄 (Damping of RC and SFRC Beams)

  • 강보순
    • 한국철도학회논문집
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    • 제8권2호
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    • pp.122-127
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    • 2005
  • In this paper, damping behavior of steel fiber reinforced concrete(SFRC) beams by experimental and numerical method is discussed. Because of its improved ability to dissipate energy, SFRC has a better damping behavior than that of reinforced concrete(RC). Damping behavior is influenced by longitudinal reinforcement ratio, volume md type of steel fiber, strength of concrete and the stress level. Damping in the SFRC beams has been evaluated from dynamic experimental test data at various levels of cracked states in the beams. A FEM program(TICAL) has been developed based on the relationships between curvature and damping. It is observed far SFRC beams with 0.44$\%$ of tensile reinforcement steel that approximate 5$\%$ to 35$\%$ was relatively increased in the damping ratio generally depending on the load level.

국내 강섬유를 사용한 강섬유보강 콘크리트 슬래브 모델의 균열 및 변형특성 (Crack and Deformation Behaviors of Steel Fiber Reinforced Concrete Slab Model Specimens Using Domestic Steel Fiber)

  • 박승범;홍석주;이봉춘;조춘근
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.319-324
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    • 1999
  • This study is to investigate the properties on the load-deflection and fracture behaviors of the steel fiber reinforced concrete(SFRC) slab model specimens, Steel fibers of indent, crimp, and end hook shape were considered to reinforce the matrix under various mixing conditions and proportions. Initial cracking load, maximum load, and energy absorption capacity(load carrying capacity) of SFRC panel specimen increased with increase of steel fiber contents. And the plain concrete slab was fractured abruptly after maximum load but SRFC slabs were fractured smoothly by steel fibers in concrete matrix operated as cracking resistance force after maximum load. Indent, crimp and end hook shape steel fibers were effective in reinforcing the matrices but end hook type fiber were superior to indent and crimp type fibers.

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SFRC 보에 대한 System Identification (System Identification on SFRC Beam)

  • 이차돈
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1991년도 봄 학술발표회 논문집
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    • pp.3-7
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    • 1991
  • Considering the relatively large amount of stable flexural teat results available for steel fiber reinforced concrete (SFRC) and their dependency on the constitutive behavior of the material, a technique called “System Identification” is used for interpretating the flexural test data in order to obtain basic information on the tensile constitutive behavior of steel fiber reinforced concrete. “System Identification” was successful in obtaining optimum sets of parameters which provide satisfactory matches between the measured and predicted flexural load-deflection relationships.

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강섬유보강콘크리트의 압축거동 특성을 반영한 기둥의 내폭해석 (Numerical Study on Columns Subjected to Blast Load Considering Compressive Behavior of Steel Fiber Reinforced Concrete )

  • 김재민;이상훈;김재현;김강수
    • 한국구조물진단유지관리공학회 논문집
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    • 제27권5호
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    • pp.105-112
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    • 2023
  • 강섬유보강콘크리트는 일반 콘크리트에 비해 높은 강도 및 우수한 에너지 소산 능력을 보이며, 폭발하중 작용 시 균열 전파 및 파편 발생을 감소시킬 수 있다. 본 연구에서는 유한요소해석 프로그램인 LS-DYNA에 SFRC 재료물성을 구현하고자 콘크리트 비선형 재료모델인 K&C 모델의 파괴 곡면(Failure surface) 및 손상 함수(Damage function)를 정의하는 파라미터를 제안하였다. 제안 파라미터 검증을 위하여 단일요소해석을 수행하였으며, 제안 파라미터가 적용된 재료모델은 SFRC 재료시험 거동을 상당히 유사하게 모사하는 것으로 나타났다. 또한, 강섬유 혼입률에 따른 SFRC 기둥의 성능을 평가하기 위하여 내폭해석을 수행하였으며, KOSHA 규정을 참조하여 섬유 혼입률에 따른 SFRC 기둥의 내폭성능을 정량적으로 분석하였다.

강섬유보강 콘크리트의 휨인성에 영향을 미치는 실험방법적 요인 (The Test Methodological Effects on the Flexural Toughness of Steel Fiber Reinforced Concrete)

  • 한승환;이형준;오병환;조재열
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1998년도 가을 학술발표논문집(II)
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    • pp.380-385
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    • 1998
  • Nowadays, shotcrete plays an essential part in he construction of underground structures, and steel fiber is so useful for increasing the toughness of the concrete that is spotlighted at tunnel or pavement site. A variety of tests have been developed to measure and quantity the improvements achievable in steel fiber reinforced concrete(SFRC) and shotcrete. But Korea doesn`t have specific standards in this respect, and the only criteria that KHC(Korea Highway Corporation) applies to tunnel shotcreting are flexural strength and toughness quotient. Test results in order to manage the quality of steel fiber reinforced concrete and shocrete are very affected by various test method. Therefore, this study deals with the test methodological effects on SFRC quality. The major interests are loading method, that is, load control and displacement control, loading velocity, support condition.

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The optimum steel fiber reinforcement for prestressed concrete containment under internal pressure

  • Zheng, Zhi;Sun, Ye;Pan, Xiaolan;Su, Chunyang;Kong, Jingchang
    • Nuclear Engineering and Technology
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    • 제54권6호
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    • pp.2156-2172
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    • 2022
  • This paper investigates the optimum fiber reinforcement for prestressed concrete containment vessels (PCCVs) under internal pressure. To achieve this aim, steel fiber, which is the most widely used fiber type in current engineering applications, is adopted to constitute steel fiber-reinforced concrete (SFRC) to substitute the conventional concrete in the PCCV. The effects of characteristic parameters, 𝜆sf, of the steel fiber affecting significantly the mechanical behavior of the concrete are first taken into account. Partial or complete concrete regions of the PCCV are also considered to be replaced by SFRC to balance the economy and safety. By adopting the ABAQUS software, the ultimate bearing capacity and performance for the fiber-reinforced PCCV are scientifically studied and quantified, and the recommendations for the optimum way of fiber reinforcement are presented.