• 제목/요약/키워드: fiber form

검색결과 620건 처리시간 0.023초

셀룰로오스 섬유보강 콘크리트를 사용한 기계화경작로 확·포장공사의 현장사례 연구 (Field Case Study of Mechanized Form Roads Pavement Construction using Cellulose Fiber Reinforced Concrete)

  • 박종건
    • 한국농공학회논문집
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    • 제57권2호
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    • pp.47-56
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    • 2015
  • At the present, the mechanized form roads pavement was constructed with plain concrete. Mostly, it was used by welded wire mesh for preventing crack. Cellulose fibers for the reinforcement of concrete offer relatively high levels of elastic modulus, fiber count (per unit weight), specific surface, and bond strength to cement-based materials. The construction of concrete pavement confirmed that cellulose fiber reinforced concrete was applicable to mechanized form roads pavement. In the study, cellulose fibers were used here at 0.08 % volume fraction, which is equivalent to a fiber content of $1.2kg/m^3$. Cellulose fiber reinforced concrete were compared with plain concrete. Field test results indicated that cellulose fiber reinforced concrete showed slightly to increase of 28 days compressive strength and improved the initial strength. it tended to increase of splitting tensile strength. Test results showed that the slump and air content tend to decreased. but, the variation of air contends is very little. Also, construction cost of cellulose fiber reinforced concrete is less than about 25.7 % the case of welded wire mesh previously used. Therefore, The cost reduction is expected to be possible in construction site by mechanized form roads pavement.

강화형 strip crown의 사용 (GLASS FIBER REINFORCED STRIP CROWN IN PRIMARY TEETH)

  • 김대업
    • 대한소아치과학회지
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    • 제32권1호
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    • pp.132-135
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    • 2005
  • 본 연구의 목적은 유전치 심미수복의 새로운 방법으로 glass fiber를 이용한 강화형 strip crown의 사용을 제시하고자 하는 것이다. Strip crown의 제작을 위하여 celluloid crown form(3M, USA)과 복합레진은 Z100(P shade, 3M, USA)을, 유동성 복합레진은 Aeliteflo(Bisco Inc., USA)를 사용하였다. 상아질 결합제는 Clearfil SE Bond(Kuraray Medical Inc., Japan)를 사용하였고 강화를 위하여 그물형 glass fiber(TESCERA Fiber Mesh, Bisco Inc, USA)를 사용하였다. 적절한 크기의 celluloid crown form을 성형하여 삭제된 치아에 시적한 후 레진 접착제와 유동성 복합레진으로 처리한 그물형 glass fiber를 설측 내면에 삽입하고 광중합하였다. 잔여 공간에 복합레진을 채우고 치아에 끼운 다음 광중합하였다. 복합레진의 심미성은 유지하면서 glass fiber로부터 기계적 장점을 얻을 수 있을 것으로 사료된다. 새로운 강화형 strip crown의 물성에 대한 후속연구가 필요하다.

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스트립형의 섬유 면진 베어링의 실험적 해석 (An Experimental Study on Fiber Reinforced Strip Form Isolator)

  • 문병영;강경주;강범수
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2002년도 춘계 학술발표회 논문집
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    • pp.409-416
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    • 2002
  • 기존의 면진 기술을 일반건물에 적용하기 위해서는 낮은 가격과 낮은 무게로 면진 베어링이 제작 및 공급되어야 한다. 이에 본 논문에서는 일반건물에 면진 기술을 적용하기 위한 방법으로 기존의 적층고무 면진 베어링에 철판을 대체하여 섬유로 보강하고, 고무와 섬유의 층으로 구성된 벨트 타입의 면진 베어링을 제안하였다. 또한 제안한 섬유보강 면진 베어링을 설계 및 제작하여 수직실험과 수평실험을 수행하여 그 성능을 검증하였다. 따라서, 스트립형의 면진 베어링이 제작가능하며 일반건물의 필요한 크기로 절단이 가능함을 보였다. 또한 수평 실험 수직 실험을 통해서 기존의 적층고무 면진 베어링을 대체하여 사용할 수 있는 결과를 보였다. 이와 같은 결과를 통해서 일반건물에 낮은 무게와 낮은 가격의 면진 베어링을 공급할 수 있음을 보였다. 이 연구결과로 인해 스트립형의 섬유보강 면진 베어링이 저가건물에 널리 사용될 수 있을 것으로 기대된다.

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스트립형 섬유 보강 탄성받침의 실험에 의한 기계적 특성해석 (Mechanical Characteristic Analysis of Fiber Reinforced Strip Form Elastomeric Bearing by Experiment)

  • 강경주;문병영;강범수;김계수;박진삼
    • 한국지진공학회논문집
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    • 제6권6호
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    • pp.1-6
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    • 2002
  • 기존의 면진 기술을 일반건물에 적용하기 위해서는 낮은 가격과 낮은 무게로 면진 탄성받침 이 제작 및 공급되어야 할 필요가 있다. 이에 본 논문에서는 일반건물에 면진 기술을 적용하기 위한 방법으로 기존의 적층고무 면진 탄성받침에 철판을 대체하여 섬유로 보강하고, 고무와 섬유의 층으로 구성된 스트립형의 면진 탄성받침을 제안하였다. 또한 제안한 섬유보강 면진 탄성받침을 설계 및 제작하여 수직실험과 수평실험을 수행하여 그 성능을 검증하였다. 따라서, 스트립형의 면진 탄성받침이 제작가능하며, 필요한 크기로 절단이 가능함을 보였다. 또한 수평 실험 수직 실험을 통하여 기존의 적층고무 면진 탄성받침을 대체하여 사용할 수 있음을 보였다. 이 연구결과로 인해 스트립형의 섬유보강 면진 탄성받침이 저가건물에 널리 사용될 수 있을 것으로 기대된다.

Characteristics of Optical Current Sensors by Sensor Design

  • Kim, Young-Min;Park, Jung-Hwan;Lee, Kwang-Sik;Kim, Jung-Bae;Park, Won-Zoo
    • 조명전기설비학회논문지
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    • 제21권4호
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    • pp.80-87
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    • 2007
  • This paper will suggest that the 1 cross orthogonal loop type sensor improves on the orthogonal loop form sensor-head, which is available a calibration of the linear birefringence, when a fiber optic current sensor was composed. An output characteristics of the 1 cross orthogonal loop form, a general closed loop form, the orthogonal loop form are compared by the IEC(International Electrotechnical Commission) 60044-8 standard, and the state of polarization is compared with three forms. As a result, when the closed loop form was changed to the orthogonal loop form, retardation decreased 15.3[%]. When the closed loop form was changed to the 1 cross orthogonal loop type, the retardation decreased 33.8[%]. As a result of the Faraday Effect measurement, the 1 cross orthogonal loop form has the highest output characteristic and the lowest error ratio. It met the 0.5 class of the IEC 60044-8 standard. Thus, in application of the 1cross orthogonal loop form, the possibility to develop high reliability fiber optic current sensors that have a high output and stable error ratio rises is increased.

경남지역의 실내외 공기 중 총섬유 입자의 농도특성 및 석면 입자의 확인 (Concentration Characteristics of Indoor and Outdoor Airborne Total Fiber Particles and Identification of Asbestos in Gyeongnam Provinces)

  • 박희은;박정호;김형갑
    • 한국산업보건학회지
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    • 제22권2호
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    • pp.119-127
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    • 2012
  • Objectives: The aim of this study is to identify concentration characteristics of indoor and outdoor airborne total fiber particles and asbestos in Gyeongnam Provinces. Methods: This study investigated concentration characteristics of indoor fiber particles from 748 schools and 38 public facilities as well as outdoor particles from 11 sites through PCM (phase contrast microscope). SEM/EDX (scanning electron microscope/energy dispersive using X-ray analysis) was used to obtain physicochemical information of asbestos fiber particles. The study identified asbestos rate in the 15 samples from indoor and outdoor airborne total fiber particles. Results: 1. The average indoor airborne concentrations of total fiber particles were $0.0011{\pm}0007$ f/cc in schools and $0.0015{\pm}0007$ f/cc in public facilities by PCM. Over 90% of the fiber particles were identified as single fibers. 2. The average outdoor airborne concentrations of total fiber particles were $0.0007{\pm}0002$ f/cc, and they were lower than those of indoor airborne concentrations. 3. The results showed that the form of asbestiform was diverse as skein of thread like form and long needle, which was relatively narrower than that of glass fiber and rock wool. 4. The results of SEM/EDX analysis of 15 areas where total fiber particle was relatively high showed that the form was rather similar to that of asbestos, but chemical composition was proven to be non-asbestos. Conclusions: The concentration of indoor and outdoor airborne total fiber particles of Gyeongnam Provinces satisfied the IAQ (Indoor air quality) level of 0.01 f/cc and asbestos was not found in most of the samples by SEM/EDX.

비탈형 영구거푸집용 굳은모르터의 특성에 관한 연구 (A Study on The Mechanical Properties of Permanent Form Mortar)

  • 김우재;이영도;임남기;김성식;문장수;정상진
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
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    • pp.166-173
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    • 1997
  • The present problem of this country building market in the face of 3D, in addition to a rise in construction cost, materials problems and opening a building market to foreign countries, is finding the efficient ways of overcoming these problems. So the efficacy of form work in technical improvement becomes important through scientific methods of the design and construction as advancement in th study of strength for Permanent form mortar is possible. According to the increment of polymer-cement ration, the degree of bending strength and compressive strength and impact strength increases. The optimum volume content of glass fiber seemed to be about 2.5% considering the distribution of glass fiber, workability and economy.

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횡구속 방법에 따른 고성능 RC 기둥 콘크리트의 내화특성 (Properties of Fire Endurance of High Performance RC Column with Laterral Confinement Method)

  • 황인성;김기훈;배연기;이보형;이재삼;한천구
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2004년도 추계 학술발표회 제16권2호
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    • pp.553-556
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    • 2004
  • This paper is to investigate the spalling and fire endurance of high performance RC column member with PP fiber and lateral confinement of metal lath and non fire resistance removal type form. According to test results, combination of PP fiber and metal lath as well as use fire resistance non removal type form had favorable fire resistance by discharging internal vapour pressure and lateral confining. After fire endurance test, compressive strength decreased markedly caused by internal expansion pressure and crack. Residual strength of plain concrete was decreased to $22\%$. The use of PP fiber and lateral confinement of metal lath and non removal type form enhanced the residual strength above $40\%$. Especially, the combination of $0.1\%$ of PP fiber and lateral confinement with the level of 2.3T exhibited more than $51\%$ of residual strength. Therefore, to improve fire endurance and spalling resistance, the combination of $0.1\%$ of PP fiber and metal lath with 2.3T can be the proper measure.

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비탈형 영구거푸집의 현장 적용을 위한 실험적 연구 (An Experimental study on field application of Permanent form)

  • 정근호;김우재;이영도;정재영;정상진
    • 한국건축시공학회지
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    • 제1권1호
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    • pp.143-150
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    • 2001
  • Permanent-Form is one of system forms for reducing human labor, work costs, oscillation, noise, construction wastes and so on. Permanent-Form is made from precast method in facilities, and carried in construction site to assemble with no demolding. The biggest expense to produce permanent-Form is about manufacturing mold. This papers about structural efficiency evaluation, construction efficiency test. The result of this study is below. (1) In the compressive strength test of column. Fly ash specimen and polymer specimen's strength developed as each 8%, 14% to comparison with standard specimen. The reason of this result from form section area increase and form's reinforcing bar (2) The Degree of column crack in permanent form is lower than another one's The glass fiber's fiber reinforcement effect brings like this. (3) In the flexural load test of beam, the early crack load and maximum load of permanent form use specimen showed 20% higher than standard specimen's. (4) In field application experiment, an constructional error is satisfied with the allowable margin of error, $\pm$5mm (5) When the concrete is placed into the form inside, The transformation degree of permanent form is lower than plywood form's. (6) The concrete packing ability of permanent form is satisfactory. (7) The bonding strength of permanent form shows enough strength - 6kgf/$\textrm{cm}^2$.

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