• 제목/요약/키워드: fiber evaluation

검색결과 1,680건 처리시간 0.022초

시편형상에 따른 강섬유보강 콘크리트의 휨인성평가방법 (Toughness Evaluation of Steel Fiber Reinforced Concrete to Spiecimen Types)

  • 류종현;김진철;한승환;이상돈;안태송
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.341-344
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    • 2001
  • Fiber reinforced shotcrete(FRS) is widely used in tunnel linings, which strengthen the rock surface and reduce the loosening of the rock strata. The advantages of FRS in tunnel linings are the unsusceptibility to crack, the benefit of shotcrete strength, and the superiority of toughness. In this study, the several evaluation methods of FRS toughness were investgated experimentally, which included the ASTM beam test, EFNARC square panel test and RTA round panel test. Especially, it was examined that the round panel test could fulfill the toughness evaluation of FRS.

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식이섬유 첨가가 절편의 특성에 미치는 영향에 관한 연구 (A Study on the Effect of Addition of Dietary Fibers on Quality of Julpyun)

  • 이지영;구성자
    • 한국식품조리과학회지
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    • 제10권3호
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    • pp.267-276
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    • 1994
  • Recent epidemological observations suggested beneficial effects of dietary fiber on man's health. With the increased emphasis placed on the requirement for dietary fiber in the diet, there has been greater interest in successfully incorporating dietary fiber into food products. Hence, in this study, several dietary fibers such as cellulose, pectin, rice bran, barley bran and job's tears bran were incorporated into julpyun to determine their effects on some physical properties and sensory characteristics. Difference of water binding capacity(WBC) was found among dietary fiber sources. The WBC of pectin was highest and that of job's tears bran was lowest. The moisture contents of julpyun were increased as WBC of added dietary fiber sources was higher. In the rheometer measurement for julpyun added with dietary fiber, hardness of julpyuns added with cellulose and pectin was low. But, hardness of julpyun added cellulose was increased rapidly during storage at 4$^{\circ}C$. Springiness and gumminess wereshowed similar aspects to hardness. In the retrogradation speed by Avrami equation, the rate constant of julpyun added barley bran was low ao retrogradation occurred slowly. The results of sensory evaluation, julpyun added no dietary fiber showed good overall preference. Overall preference in sensory evaluation showed positive correlation with the after-swallowing and color.

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강섬유보강 콘크리트의 휨인장강도 특성을 고려한 휨강성 평가 (Evaluation of Flexural Stiffness Considering Flexural Tensile Strength of Steel Fiber Reinforced Concrete)

  • 홍건호;정승원
    • 대한건축학회논문집:구조계
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    • 제35권8호
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    • pp.131-138
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    • 2019
  • Since concrete has a low tensile strength compared to the compressive strength, reinforced concrete flexural members represent easy crack occurance under a small load. In order to overcome this problem, steel fiber reinforced concrete has been developed to compensate the tensile strength and brittleness of members. However, in the design formula of the domestic building code, it is not specified in the design formula reflecting the material characteristics. Therefore, the field application of the steel fiber reinforced concrete have had many restrictions. In this study, a flexural tensile strength model of steel fiber reinforced concrete is proposed by collecting and analyzing the material properties of material test results conducted by various researchers, and verified by the test results of cracking and stiffness evaluation of flexural members based on the proposed model. As a result of this study, the flexural tensile strength model of steel fiber reinforced concrete which can reflect the mixing ratio and aspect ratio of the steel fiber was proposed and the validity of the proposed material model equation was evaluated from the load-deflection relationship in the flexural test of the slab member.

콘크리트의 휨성능 증진 및 균열제어에 대한 특수 가공된 셀룰로오스섬유의 효과 (Effects of Specialty Cellulose Fibers on Improvement of Flexural Performance and Control of Cracking of Concrete)

  • 원종필;박찬기
    • 콘크리트학회논문집
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    • 제12권2호
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    • pp.89-98
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    • 2000
  • The mechanical properties of specialty cellulose fiber reinforced concrete and the contribution of specialty cellulose fiber to drying shrinkage crack reduction potential of concrete and theirs evaluation are presented in this paper. The effects of differing fiber volume fraction(0.03%, 0.06%, 0.08%, 0.1%, 0.15%, 0.2%) were studied. The results of tests of the specialty cellulose fiber reinforced concrete were compared with plain and polypropylene fiber reinforced concrete. Flexural performance(flexural strength and flexural toughness) test results indicated that specialty cellulose fiber reinforcement showed an ability to increase the flexural performance of normal- and high- strength concrete(as compared to plain and polypropylene fiber reinforced concrete). Optimum specialty cellulose fiber reinforced concrete were obtianed using 0.08% fiber volume fraction. Drying shrinkage cracking test results confirmed specialty cellulose fibers are effective in reducing the drying shrinkage cracking of normal and high-strength concrete(as compared to popylene fiber reinforced concrete).

강섬유보강 시멘트 복합체의 섬유인발거동에 따른 인장성능 평가에 관한 실험적 연구 (An experimental study on the tensile performance evaluation of steel fiber reinforced cementitious composites according to fiber pull-out behabior)

  • 이예찬;김규용;남정수;이상규;서동균;유하민
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2020년도 가을 학술논문 발표대회
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    • pp.155-156
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    • 2020
  • The purpose of this study is to evaluate tensile performance of cementitious composites reinforced with steel fiber. The tensile performance of steel fiber reinforced cementitious composites is related to the tensile performance of reinforced fiber, and depends on the fracture or pull-out of fiber. Therefore, the tensile performance was compared and analyzed by conducting a direct tensile test on the tensile specimens of cementitious composites reinforced with hook-type steel fiber and amorphous steel fiber.

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Evaluation of Structural Integrity and Performance Using Nondestructive Testing and Monitoring Techniques

  • Rhim, Hong-Chul
    • 한국지진공학회논문집
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    • 제2권3호
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    • pp.73-81
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    • 1998
  • In this paper, the necessity of developing effective nondestructive testing and monitoring techniques for the evaluation of structural integrity and performance is described. The evaluation of structural integrity and performance is especially important when the structures and subject to abrupt external forces such as earthquake. A prompt and extensive inspection is required over a large area of earthquake-damaged zone. This evaluation process is regarded as a part of performance-based design. In the paper, nondestructive testing and monitoring techniques particularly for concrete structures are presented as methods for the evaluation of structural integrity and performance. The concept of performance-based design is first defined in the paper followed by the role of evaluation of structures in the context of overall performance=based design concept. Among possible techniques for the evaluation, nondestructive testing methods for concrete structures using radar and a concept of using fiber sensor for continuous monitoring of structures are presented.

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플라스틱 섬유재와 슬래그 시멘트를 이용한 고강도 간격재의 개발 및 적용성 평가 (Applicability Evaluation and Development of High Strength Spacer with Plastic Fiber and Slag Cement)

  • 권성준;조홍준;박상순
    • 한국구조물진단유지관리공학회 논문집
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    • 제18권4호
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    • pp.92-98
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    • 2014
  • 본 연구는 환경부하 저감을 위해 슬래그 시멘트를 사용하고 플라스틱 섬유보강재(폴리프로필렌, 나일론, 유리섬유)를 혼입하여 고강도 간격재를 개발하고 현장적용성을 평가하는 연구이다. 이를 위해 예비실험을 통하여 4가지 섬유 복합재의 첨가량이 결정되었다. 또한 역학적 시험(압축, 휨, 인장) 및 내구성 시험(흡수율, 투수율, 길이변화율, 균열저항성, 탄산화, 동결융해)을 통하여 최적의 섬유재를 도출하였으며, 이를 이용한 고강도 섬유재 간격재의 배합 및 생산시스템을 개발하였다. 또한 현장적용성 평가를 통하여 개발된 간격재의 구체 콘크리트 일체성을 확인하였다.

Skin biopsy: an emerging method for small nerve fiber evaluation

  • Sohn, Eun Hee
    • Annals of Clinical Neurophysiology
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    • 제20권1호
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    • pp.3-11
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    • 2018
  • Skin biopsy and staining the specimens with immuno-reactive markers has been proven to be a useful method to demonstrate the pathologic status of small nerve fibers. Quantification of intraepidermal nerve fiber density using anti-protein gene product 9.5 antibody is a standard method to diagnose small fiber neuropathy. Skin biopsy also makes it possible to differentiate the nerve fibers according to their function by using different markers. Quantification of dermal structures with different types of nerve fibers could reveal the pathophysiologic mechanism of the disease state.

비정질 강섬유 보강 콘크리트 강도 특성 평가 및 실증하우스 적용성 검토 (Strength Property Evaluation of Amorphous Steel Fiber-Reinforced Concrete and Applicability Review of Test House)

  • 성종현;최세진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.38-39
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    • 2015
  • This study reviewed slump and air content as pre-hardening characteristics depending on B/P production of amorphous steel fiber-reinforced concrete and evaluated compressive strength, flexural strength and tensile strength as post-hardening characteristics depending on B/P production of amorphous steel fiber-reinforced concrete.

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