• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.95-96
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• 2023

In this study, the table flow of fiber reinforced cement composites mixed with CNTs dispersed differently according to the dispersion method was evaluated. The mixture was composed of plain mixture according to the presence or absence of ultrasonic dispersion and PCE-based dispersants A and B of 0.5% and 1.0%, respectively, CNT was mixed with 0.03% of cement weight and fiber was mixed with 1.5% of total volume. As a result of the experiment, NC-A0.5 showed a fluidity similar to that of P without CNT. The fluidity of NC-A0.5 and P-N showed a similar tendency, which is considered to be due to the distribution of evenly dispersed CNT particles without agglomeration between cement particles due to the dispersant. NC-B0.5 showed a similar level of firmness to P-U, but after hitting 250 mm, B Agent seems to have a significant effect on liquidity improvement.Both NC-A1.0 and NC-B1.0 seem to have increased flow due to excessive dispersion.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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• pp.473-476
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• 2006

In this study, evaluation of fire-resistant performance for polypropylene fiber-mixed mortar was performed to establish specification for stability of tunnel structure against fire afterward. In the fire-resistant performance test with mix proportion of polypropylene fiber, cracks were observed for mortar under 0.15% of fiber content, but micro-cracks were remarkably reduced for mortar more than 0.2% of fiber content. From the results, we are concluded that optimal mix proportion of polypropylene fiber is $0.20{\sim}0.25%$.

• Journal of the Korean Wood Science and Technology
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• 제29권3호
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• pp.27-35
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• 2001

Four different sources of wood-fibers from Eucalyptus, Italian poplar, hemlock, and mixed species fibers were used to study the influence of their fiber characteristics on the performance of medium density fiberboard (MDF) panels bonded with both urea-formaldehyde (UF) and phenol-formaldehyde (PF) adhesives. Included fiber characteristics were fiber length, size distribution, bulk density, and acidity. Physical and mechanical properties of MDF panels manufactured by dry process using these different fibers were determined for the comparison of board performance. Two hardwood species had a large fraction of short fibers resulting in a higher bulk density while very long hemlock fibers had lower bulk density. Fiber acidity was revealed to strongly affect the internal bond (IB) strength of MDF panels bonded with UF resins. MDF panels made from mixed species fibers showed highest IB strength of all panels prepared. UF-bonded MDF panels showed poor dimensional stability. In conclusion, the present study showed that wood-fiber characteristics such as fiber length, bulk density, and acidity affect the performance of MDF boards, and also suggested that fiber characteristics be considered for MDF panel manufacture.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.61-64
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• 2009

This study is reviewed fire resistance characteristics of high strength concrete according to changes in PP fiber mixing ratio and type of fine aggregate, and the results can be summarized as follows. As fire resistance characteristics, all plain crushed sands prevented spalling regardless of increase in mixing ratio of PP fiber. Mixtures other than the plain showed satisfactory spalling prevention when 0.05 % or more of PP fiber was mixed. After the fire resistance experiment, the plain showed 5.5 % of mass loss rate when fiber was not mixed and others could not be measured. According to increase in mixing ratio of fiber, river sand with fineness modulus of 2.2 showed most satisfactory result of 34 %${\sim}$42 %. Mass loss rate after fire resistance experiment was most satisfactory at about 10 % in the plain crushed sand without mixing of fiber, and all other mixes with 0.05 % PP fiber or more showed 5${\sim}$10 % loss rate.

• 한국지반공학회논문집
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• 제19권4호
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• pp.75-81
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• 2003

초연약 고소성의 준설해성점토를 보강하기 위하여 Micro-Fiber(MF)재를 혼합하여 다양한 실내시험을 수행하였다. 준설점토의 함수비를 3종으로 조정하고 각각의 시료에 MF를 길이와 혼합율을 변화시키면서 일축압축 및 삼축압축 시험을 통하여 보강특성을 검토하였다. 또한, 양생일수벽로 강도증가 경향을 평가하였으며, 폐석회(Waste Lime, WL)의 추가혼합이 보강기능을 증대시키는지 여부를 검토하였다. 실험결과, MF를 혼합함에 따라 준설점토의 강도가 자연함수비에 무관하게 약 50% 증가하였으며, MF의 길이가 길수록 보강효과가 크게 나타났다. 또한, 합리적인 MF의 혼합율은 2% 정도이며, 추가적으로 폐석회를 약 10% 혼합할 경우 중장비주행이 가능한 보강효과가 나타나는 것을 확인하였다.

• 펄프종이기술
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• 제42권3호
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• pp.22-27
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• 2010

Pulping properties of the imported mixed eucalyptus chips and the domestic yellow poplar chips were investigated for comparing two chips as the raw materials for the hardwood chemical pulp. Soda-AQ (anthraquinone) pulping was applied for this study. The pulp from yellow poplar showed higher pulp yield than pulp from mixed eucalyptus, which comes from the lower hot-water soluble extractives and the higher polysaccharides in yellow poplar chips than those of the mixed eucalyptus chips. The yellow poplar pulp had higher average fiber length and fiber width than those of the mixed eucalyptus pulp, which led to the better respond to beating and the higher tear strength than those of the pulp from the mixed eucalyptus chips.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.381-384
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• 2008

본 연구에서는 폭렬방지용 합성섬유의 효과적인 투입방안 마련을 목적으로, 섬유혼입 프리믹스시멘트 결합재를 사용한 고강도 콘크리트의 폭렬방지 및 내화특성을 검토하였다. 내화시험 결과, 원주형 공시체의 폭렬은 W/C 15%의 수동투입에서 일부 박리 또는 파괴폭렬이 발생한 것을 제외하고 대부분 방지되었고, 전체적으로 섬유혼입 프리믹스시멘트는 폭렬방지 성능이 섬유 수동투입과 비교하여 동등 이상으로 우수하였으며, 결합재량이 많아 점성이 큰 고강도 콘크리트일수록 양호한 섬유의 분산성으로 폭렬방지에 더욱 효과적인 것으로 나타났다. 또한, 섬유혼입 프리믹스시멘트 결합재를 사용한 기둥부재의 온도이력은 폭렬이 방지되어 철근이 노출되지 않으면 최외곽 철근의 온도가 내화성능기준의 평균온도 538$^{\circ}C$를 넘지 않는 것으로 나타나, 고강도 콘크리트의 내화기준을 만족하였다.

• 한국지반공학회논문집
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• 제31권6호
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• pp.15-25
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• 2015

본 연구는 연약지반의 강도증진을 목적으로 친환경 헤어섬유를 혼입한 점토흙의 강도 특성을 파악하였다. 본 연구에서는 헤어섬유의 길이 및 혼입율, 시멘트의 첨가량, 양생기간을 변화시키며 헤어섬유 혼입 점토흙의 압축강도 및 인장강도를 조사하였으며, 또한 응력-변형율 특성을 조사하였다. 시험결과, 헤어섬유 혼입점토는 압축 및 인장 모두에서 강도증진을 보였으며, 특히 인장강도에서 보다 큰 효과가 있는 것으로 나타났다. 뿐만 아니라, 헤어섬유 혼입점토가 파괴시까지 더 큰 변위를 허용하는 것으로 나타났다. 이와같은 결과를 토대로 향후 점토지반 강도증진을 위해 친환경 재료인 헤어섬유를 실무적으로 활용해도 될 것으로 판단된다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1986년도 학술발표초록집
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• pp.35-35
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• 1986

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2000년도 봄 한국섬유공학회 학술발표회 논문집(Proceedings of the Korean Textile Conference)
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• pp.85-88
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• 2000