• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.521-524
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• 2005

This study is an experiment for reducing effect of explosive spalling by fiber addition ratio and kinds of fiber at high performance concrete. So, high strength concrete were made addition to PVA and PP fiber as diameter of 34, 100 $\mu$m and 40 $\mu$m by fiber addition ratio as 0.05, 0.1, 0.3$\%$. After those were heated respectively for 30 in accordance with Standard Time-Temperature Curve. And then conditions of explosive spalling were divided into four grades, and characters of explosive spalling were investigated.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.11-12
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• 2014

In this study, fundamental properties of concrete mixed with fiber has been analysed. Compressive strength, tensile strength and plastic shrinkage has been tested to conduct the optimum addition ratio of fiber. Effect to control press concrete's cracking has been tested. The following results could be made as the conclusion. For the flowability, slump decreased about 41-79% when all types of fiber used in the concrete. When the addition ratio of fiber is 1.2%, the slump of concrete decreased about 45%. For the strength properties. all the specimens with different addition ratio of fiber shown higher compressive strength comparing with Plain. Comparing with Plain, cracking decreased when the fiber added. Especially, when NY fiber used in the concrete, the plastic shrinkage did not occurred. In addition, Latex modified concrete(LMC) has improved superior physical and chemical properties. The properties of latex, combined with the low water-cement ratio, produce a concrete that has improved flexural, tensile, and bond strength, lower modulus of elasticity, increased freeze-thaw resistance, and reduced permeability compared to conventional concrete of similar mix design.

• 한국환경복원기술학회지
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• 제5권6호
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• pp.37-42
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• 2002

This study has been performed to investigate the physical and mechanical characteristics of compaction, volume change and compressive strength for reinforced soil mixed with polypropylene fiber, and to confirm the reinforcing effects with admixture such as polypropylene fiber. To this end, a series of compaction test and compression test was conducted for clayey soil(CL) and polypropylene fiber reinforced soil. In order to determine proper moisture contents and mixing ratio, pilot test was carried out for natural soil and PFRS(polypropylene fiber reinforced soil). And the mixing ratio of mono-filament fiber and fibrillated polypropylene fiber admixture was 0.1%, 0.3%, 0.5% and 1.0% by the weight of dry soil. From the experimental results, it was found that the optimum moisture contents(OMC) increased with the mixing ratio of fiber, but the maximum dry unit weight and the volume change was decreased with the mixing ratio. It means that the improvement of the workability and the reduction of the weight of embankment was done by the addition of the polypropylene fiber. And, from the compression test results, it was found that the addition of the polypropylene fiber remarkably improved the compressive strength of PFRS. And it was observed in the viewpoint of strength that the fibrillated polypropylene fiber reinforced soil was more effective than the mono-filament polypropylene fiber reinforced soil.

• 한국건설순환자원학회논문집
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• 제8권2호
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• pp.198-203
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• 2020

콘크리트는 초기에 인장강도가 확보되지 못하므로 건조수축과 같은 재료적인 균열이 발생하게 된다. 본 연구에서는 셀룰로오즈 섬유를 0.0 ~ 2.0% 혼입한 콘크리트를 대상으로 공기량, 슬럼프와 같은 작업성을 평가하였으며, 재령에 따른 압축 및 인장강도를 평가하였다. 혼입률이 증가할수록 1.0kg/㎥ 수준에서는 공기량 및 슬럼프에서 저하를 확인할 수 없었으며, 이러한 작업성은 2시간까지 유효하게 작용하였다. 강도 평가에서는 혼입률이 증가할수록 인장 및 압축강도가 개선되었으며, 압축강도의 경우 7 ~ 9%수준으로, 인장강도에서는 7 ~ 22% 수준으로 증가하였다. 인장강도에서 증가율이 상대적으로 크게 평가되었는데, 이러한 효과는 균열저항성에 크게 도움을 주리라 판단된다. 본 연구를 통하여 2분간의 혼입 시간, 셀룰로오즈 섬유 1.0kg/㎥의 혼입률 수준이면 120분간 작업성에 큰 영향이 없으리라 평가된다.

• 한국식품조리과학회지
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• 제8권3호
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• pp.333-341
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• 1992

The physicochemical, rheological and sensory characteristics of 'BACKSULGIES', which was added with potato peel, guar gum or polydextrose, were investigated. The maximum acceptable addition ratio of dietary fiber to 'BACKSULGI' was 10%. And optimal addition ratio was 3% for all samples. The water binding capacity was affected by dietary fiber sources and incubation conditions (temperature and time). The Guar gum had me highest value of water binding capacity. The solubility was highly related with water binding capacity and me swelling power was increased with temperature increment. The degree of gelatinization was not significantly different with dietary fiber sources. But me values of gelatinization of 'BACKSULGIES' added with dietary fibers were significantly higher than mose of 'BACKSULGI' with no dietary fiber. Generally hardness and brittleness incresed along with storage time. But me hardness of 'BACKSULGIES' added with dietary fibers was significantly lower man those of 'BACKSULGI' with no dietary fiber. The retardation effect of dietary fibers for retrogradation of 'BACKSULGIES' was also proved by time constant determination of Avrami equation. Sernsory evaluation revealed that me addition of dietary fibers did not reduce the organoreptic quality. Therefore potato peel 3%, guar gum 3%, polydextrose 3% were optimum addition ratio which could be accepted as conventional 'BACKSULGI'. As me results of this study, it was proved mat the additions of dietary fibers to 'BACKSULGI' had the retardation effect of retrogradation.

• 자원리싸이클링
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• 제23권4호
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• pp.47-57
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• 2014

본 논문에서는 비정질 강섬유의 길이 및 혼입률 변화에 의한 섬유보강콘크리트의 작업성과 섬유분산성에 대한 기초연구를 수행하였다. 일반적인 슬럼프시험 외에 역슬럼프 및 베베시험을 이용하여 일반 강섬유와는 외관 및 형상이 다른 비정질 감섬유의 유동성을 평가하였다. 실험결과, 얇은 판상형의 비정질강섬유의 작업성 평가를 위해서는 일반적인 슬럼프시험보다는 진동 하에서 수행된 역슬럼프 및 베베시험을 통한 유동성 평가가 바람직한 것으로 나타났다. 결론적으로 섬유의 혼입률 및 길이 증가는 콘크리트의 유동성을 현저히 감소시켰으며, 시멘트 메트릭스내에서 섬유간 간격 또한 감소시키는 결과를 보여주었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.34-35
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• 2014

In this study, the effects of high temperatures on the compressive strength and elastic modulus of HPC with pp and jute fiber (jute fiber addition ratio: 0.075 vol%; length: 12 mm; PP fiber addition ratio: 0.075 vol%; length: 12 mm) were experimentally investigated. The work was intended to clarify the influence of elevated temperatures ranging from 20 to 500℃ on the material mechanical properties of HPC at 80 MPa.

• Advances in concrete construction
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• 제16권3호
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• pp.127-139
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• 2023

In this study, the steel fiber and the polypropylene fiber were used to enhance the mechanical properties of fully recycled coarse aggregate concrete. Natural crushed stone was replaced with recycled coarse aggregate at 100% by volume. The steel fiber and polypropylene fiber were used as additive material by incorporating into the mixture. In this test two parameters were considered: (a) steel fiber volume ratio (i.e., 0%, 1%, 1.5%, 2%), (b) polypropylene fiber volume ratio (i.e., 0%, 0.1%, 0.15%, 0.2%). The results showed that compared with no fiber, the integrity of cubes or cylinders mixed with fibers after failure was better. When the volume ratio of steel fiber was 1~2%, the width of mid-span crack after flexural failure was 5~8 mm. In addition, when the volume ratio of polypropylene fiber was 0.15%, with the increase of steel fiber content, the static elastic modulus and toughness of axial compression first increased and then decreased, and the flexural strength increased, with a range of 6.5%~20.3%. Besides, when the volume ratio of steel fiber was 1.5%, with the increase of polypropylene fiber content, the static elastic modulus decreased, with a range of 7.0%~10.5%. The ratio of axial compression toughness first increased and then decreased, with a range of 2.2%~8.7%. The flexural strength decreased, with a range of 2.7%~12.6%. On the other hand, the calculation formula of static elastic modulus and cube compressive strength of fully recycled coarse aggregate with steel-polypropylene fiber was fitted, and the optimal fiber content within the scope of the test were put forward.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.891-896
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• 2001

As composite materials, the addition of steel fiber in concrete significantly improves the engineering properties of structural members, notably shear strength and ductility, In this study, shear capacity evaluation method according to steel fiber contents was proposed from the literature surveys and member tests. For this, previously proposed five shear strength equation were examined and evaluated by maximum shear strength and shear capacity ratio. From the parametric study and regression analysis, following conclusion can be made; the maximum shear strength of steel fiber reinforced column will be estimated by relative shear capacity ratio.

• 한국자원식물학회지
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• 제11권3호
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• pp.358-362
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• 1998

This study was carried out to examine the effect on the contents of dietary fiber, mechanical properties, and sensory quality of bread contained with 10% of high-fiber Camellia (Camellia japonica L.) seed flour. Bread added by dietary fiber was the contents of moisture, protein and ash higher than control bread, while the contents of lipid lower than that of control bread. The high-fiber with Camellia seed flour contained 8.6% soluble dietary fiber, 43.7% insoluble dietary fiber, and 52.3% total dietary fiber. The ratio of insoluble dietary fiber/soluble dietary fiber in the high-fiber with Camelia seed flour was 5 times. Bread with the addition of dietary fiber contained 6.9% total dietary fiber. With the addition of dietary fiber, water absorption , mixing time loaf weight, and hardness increased, but the loaf volume decreased . The sensory quality on bread added by dietary fiber was somewhat low in color, appearance, crumb texture, mouthfeel, flavor and overall preference was higher than that of control bread.