• 제목/요약/키워드: aramid

검색결과 260건 처리시간 0.023초

고로슬래그 미분말과 아라미드 섬유를 이용한 보강그라우트재 개발 (Development of Reinforcement Grout Materials Using Blast Furnace Slag Powder and Aramid Fiber)

  • 서혁;박경호;김찬정;김호철;김대현
    • 한국지반신소재학회논문집
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    • 제18권1호
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    • pp.67-77
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    • 2019
  • 그라우팅 공법은 연약지반의 보강과 방수 및 지하수위저하 또는 상승과 진동으로 인한 침하 및 부등침하로 손상된 구조물의 지지력을 높이고 차수를 목적으로 하는데 사용된다. 본 연구는 아라미드 섬유를 이용하여 그라우트재료의 압축강도를 향상시키고, 고로슬래그 미분말을 이용하여 높은 강도의 지반개량공법을 개발하는데 있다. 따라서 본 연구에서는 시멘트와 고로슬래그미 분말의 비는 100:0, 70:30, 40:60%로 고치환(50%이상)까지 확인하고, 아라미드 혼입률은 시멘트와 고로슬래그 중량의 0, 0.5, 1.0%로 증가시켜 첨가하였으며, 표면의 유제처리 비율을 0.7과 1.2%로 샌드겔을 성형하여 일축압축시험을 수행하였다. 환경성 평가는 중금속용출시험과 pH 측정을 수행하였다. 실험결과 아라미드 섬유 1%첨가 시 일축압축강도는 약 1.3배 정도 강도가 증가하였고, 6가크롬은 고로슬래그 미분말이 30% 증가할수록 중금속 용출은 약 50% 감소하였으나, pH용출시험결과, 고로슬래그 미분말이 30% 증가할수록 pH는 약 0.5 증가하는 경향을 나타났다. 향후 pH에 대한 부분은 보완이 필요할 것으로 판단된다.

Dyeing of Kevlar Aramid Fiber

  • 신성철
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 1990년도 제2차 학술발표초록집
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    • pp.65-65
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    • 1990
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The Fatigue Behavior and Delamination Properties in Fiber Reinforced Aramid Laminates -Case (I) : AFRP/Al Laminates-

  • Song, Sam-Hong;Kim, Cheol-Woong
    • Journal of Mechanical Science and Technology
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    • 제17권3호
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    • pp.343-349
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    • 2003
  • The fuselage-wing intersection suffers from the cyclic bending moment of variable amplitude. Therefore, the influence of cyclic bending moment on the delamination and the fatigue crack propagation behavior in AFRP/Al laminate of fuselage-wing was investigated in this study. The cyclic bending moment fatigue test in AFRP/Al laminate was performed with five levels of bending moment. The shape and size of the delamination Lone formed along the fatigue crack between aluminum sheet and aramid fiber-adhesive layer were measured by an ultrasonic C-scan. The relationships between da/dN and ΔK, between the cyclic bending moment and the delamination zone size, and between the fiber bridging behavior and the delamination zone were studied. As results, fiber failures were not observed in the delamination zone in this study, the fiber bridging modification factor increases and the fatigue crack growth rate decrease and the shape of delamination zone is semi-elliptic with the contour decreasing non-linearly toward the crack tip.

Experimental study on reinforced high-strength concrete short columns confined with AFRP sheets

  • Wu, Han-Liang;Wang, Yuan-Feng
    • Steel and Composite Structures
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    • 제10권6호
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    • pp.501-516
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    • 2010
  • This paper is aiming to study the performances of reinforced high-strength concrete (HSC) short columns confined with aramid fibre-reinforced polymer (AFRP) sheets. An experimental program, which involved 45 confined columns and nine unconfined columns, was carried out in this study. All the columns were circular in cross section and tested under axial compressive load. The considered parameters included the concrete strength, amount of AFRP layers, and ratio of hoop reinforcements. Based on the experimental results, a prediction model for the axial stress-strain curves of the confined columns was proposed. It was observed from the experiment that there was a great increment in the compressive strength of the columns when the amount of AFRP layers increases, similar as the ultimate strain. However, these increments were reduced as the concrete strength increasing. Comparisons with other existing prediction models present that the proposed model can provide more accurate predictions.

SF_6 가스와 절연지의 절연계에서 가스압력에 따른 부분방전현상 (Partial Discharge Phenomenon with $SF_6$ Gas Pressures in Insulation consisting of Insulation Paper and $SF_6$ Gas)

  • 선종호;김광화;박정후;조정수
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권2호
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    • pp.65-71
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    • 2001
  • This paper describes partial discharge phenomenon with SF6gas pressures in insulation consisting of insulation paper and SF6 gas. We made the specimens with SF6 gas gaps which exist between aramid papers and electrodes and calculated the electric field intensity in the these gaps. We measured the partial discharge inception voltages and the AC breakdown voltages with the test method of IEC 60060-2 and did the partial discharge degradation experiments with a constant voltage. According to gas pressures, the breakdown voltages in SF6gas gaps were calculated by Paschen's law. And these results showed the ability applying partial discharge inception voltages evaluation to Paschen's law and the relationship between the PD quantities occurring insulation breakdown and PD occurring area.

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