• 제목/요약/키워드: Anchoring Strength

검색결과 88건 처리시간 0.024초

신소재 및 성능개선 디테일을 활용한 철근콘크리트 골조면내 전단벽의 내진성능 개선기술 (New Technique of Earthquake Resistant Performance of Reinforced Concrete Infilled Shear Wall using New Materials and Advanced Detailing)

  • 하기주;신종학;김윤용;양승혁;홍건호;김정수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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    • pp.202-205
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    • 2006
  • Three reinforced concrete shear wall and infilled shear wall using retrofitting system were constructed and tested under both vertical and cyclic loadings, Experimental programs were carried out to evaluate and improve the seismic performance of such test specimens, such as the hysteretic behavior, the maximum horizontal strength, crack propagation, and ductility etc. under load reversals. All the specimens were modeled in one-third scale size. For specimens(RWAHC, RWXHC) designed by the improving of seismic performance using the high ductile fiber composite mortar, anchoring, and advanced detailing system for the reinforced concrete shear wall load-carrying capacities were increased $1.1{\sim}1.22$ times in comparison with the standard specimen(SRW).

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러빙처리된 폴리스타이렌막 표면에있어서의 표면 액정 배향에관한 이방성 분산력의 효과 (Anisotropic Dispersion Force Effects for Surface Liquid Crystal Alignment on Rubbed Polystyrene Surfaces)

  • 서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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    • pp.105-108
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    • 1996
  • We have studied the anisotropic dispersion force effects for surfaces alignment of liquid crystals (LCs) on rubbed polystyrene (PS) surfaces by unidirection. In microphotographs of the textures, we obtained the nematic (N) LCs are shown to align in both direction parallel and Perpendicular to the rubbing for region up to medium rubbing, however to align in the direction perpendicular to the rubbing for strong rubbing legion. We suggest that the anisotropic dispersion force is very important rather than macro-surface groove effect to uniform alignment of LCs. We also measured the temperature dependence of extrapolation length of 5CB on rubbed PS surfaces for strong rubbing. It is shown that the polar anchoring strength of 5CB is very weak on rubbed PS surface compared to the rubbed polyimide (Pl) surface.

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넌러빙 액정배향기술을 이용한 a-TN-LCD의 전기광학특성에 관한 연구 (A Study on Electro-optical Characteristics of a-TN-LCD by Non-rubbing Liquid Crystal Alignment Techniques)

  • 서대식;이창훈;황율연;이보호
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 1996년도 추계학술대회 논문집
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    • pp.180-182
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    • 1996
  • In this study, we have investigated the characteristics of the response time and the viewing angle on twisted nematic (TN)-liquid crystal display (LCD) and amorphous (a) TN-LCD without rubbing. To measure the transmission-voltage, response time, and viewing angle characteristics, we prepared three kinds of LC cells and then studied the surface liquid crystal alignment effect. We studied that the response time on a-TN-LCD is fast compared to the TN-LCD. We suggest that the weak anchoring strength is attributed to the fast response time on a-TN-LCD. Also, we obtained the uniform viewing angle characteristics on a-TN-LCD. From these results, we consider that the liquid crystal alignment on LCD device are very important factor for electro-optical characteristics.

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연약지반용 스마트 앵커 공법 (A Method of SMART Anchor for a Weaked Ground Condition)

  • 박대웅;정종기;김정열
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.1334-1337
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    • 2009
  • A SMART anchor is a kind of friction mount anchor, the load is diffused and applied to the various parts of the distributed bond length, having less impact on the grout strength, and being able to secure necessary anchoring force in relatively soft grounds. Smart anchor can have strong loads in soft and weak grounds as in rock beds.

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CFRP판용 쐐기형 정착장치에 대한 실험적 연구 (Experimental Study on Wedge-type Anchorage System for CFRP Laminates)

  • 박종섭;박영환;정우태
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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    • pp.157-160
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    • 2006
  • Carbon fiber reinforced polymer (CFRP) laminates can be used more efficiently in strengthening applications by applying prestress to the CFRP laminates. A key problem for prestressing with CFRP laminates is anchoring the laminates. These may include fracture to the CFRP laminates due to excessive gripping force or slippage of the CFRP laminates out of the anchorage zone caused by low friction between the anchor device and the lamiantes. The main objective of this study is the development of an applicative wedge-type anchorage system for prestressed CFRP laminates through experimental study. The experimental parameters were the type of anchorage and the effect of elastic modulus of tab. The test results showed that the developed anchor assures 100% CFRP laminate strength.

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전사배향 TN-LCD의 액정배향 및 전기광학특성 (Liquid crystal alignment and EO performance of transcription-aligned TN-LCD)

  • 서대식;김진호
    • 한국전기전자재료학회논문지
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    • 제11권12호
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    • pp.1133-1138
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    • 1998
  • In this paper, we obtained the monodomain alignment of nematic liquid Crystal(NLC) in the cell fabricated by transcription alignment method on polyimide(PI) surface with side chain. It is considered that the LC alignment produced by the transcription alignment method is attributed to a memory effect of the NLC on PI surfaces. Also we observed that the generated pretilt angle of NLC is about $3.7^{\circ}$ with transcription alignment on PI surface. Next, we measured that the voltage-transmittance characteristics of transcription-aligned TN-LCD are almost same compared to rubbing-aligned TN-LCD. Also, we measured that the curve of transcription-aligned TN-LCD is less sharp than that of the rubbing-aligend TN-LCD in the decay time characteristics. It is considered that the response time characteristics of transcription-aligned TN-LCD are attributed to the weak anchoring strength between the LC molecules and the polymer surface.

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a-TN-LCD의 전기광학특성에 미치는 액정배향의 효과 (Effects of Liquid Crystal Alignment on the Electro-Optical Characteristics of a-TN-LCD)

  • 서대식;이창훈;황율연;이보호;이승희;김향율
    • E2M - 전기 전자와 첨단 소재
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    • 제10권1호
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    • pp.15-19
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    • 1997
  • The characteristics of the response time and the viewing angle on twisted nematic (TN) liquid crystal display (LCD) and amorphous (a)-TN-LCD without rubbing were investigated. To measure the tansmission-voltage, response time, and viewing angle characteristics, we prepared three kinds of LC cells and then studied the surface liquid crystal alignment effect. It was found that the response time on A-TN-LCD was fast compared to the TN-I-CD, and the weak anchoring strength was attributed to the fast response time on a-TN-LCD. Also, we obtained the wide viewing angle characteristics on a-TN-LCD. The liquid crystal alignment of LCD device for electro-optical characteristics is discussed in the present paper.

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고장력 인장봉으로 보강된 RC 보의 휨 거동에 관한 실험적 연구(3) (An Experimental Study on Flexural Behavior of RC Beams Strengthened with Hi-Strength Bars(3))

  • 신경재;김윤정;문정호
    • 콘크리트학회논문집
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    • 제19권3호
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    • pp.351-358
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    • 2007
  • 현재 상용되고 있는 강판 보강법이나 탄소섬유 시트 부착 보강법과는 달리, 고장력 인장봉을 이용한 외부 비부착 방식의 보강법은 설치가 간단하고 시공 시간이 짧은 등의 장점이 있다. 또한 외부 비부착 보강법은 콘크리트 표면처리가 필요 없고 에폭시 등의 접착제를 사용하지 않아 환경에 미치는 영향도 적다. 지난 연구에 이어 본 연구에서는 보강된 RC보에 관한 총 9개의 실대형 시험체를 변수별로 제작하여 여러 변수가 실제 구조물에 미치는 영향을 검토하였다. 시험체의 주요 변수는 보강재의 크기와 전단 보강근의 간격, 지지 조건이다. 본 논문에서는 보강된 RC 보의 구조적 거동을 무보강 시험체와 비교하여 기술하였다. 실험 결과 고장력 인장봉으로 보강된 RC보는 무보강 시험체와 비교하여 강도와 휨 성능에서 탁월한 효과를 나타내었으며 전단 보강근이 과소 배근된 시험체에서도 고장력 인장봉에 의한 전단 내력 효과를 보였다.

Asperities on the Surface of Plate-like Alumina and their Effect on Nacre-inspired Alumina-PMMA Composites

  • Kim, Bo-Yeon;Lee, Yoonjoo;Kim, Soo-Ryong;Shin, Dong-Geun;Kwon, Woo-Teck;Choi, Duck-Kyun;Kim, Younghee
    • 한국세라믹학회지
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    • 제52권4호
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    • pp.248-252
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    • 2015
  • Natural materials often have unique mechanical properties, such as the hierarchical structure of nacre formed through mineral bridges or asperities created between an inorganic particle and a natural-layer surface. As these asperities produce an exceptional shear resistance, in this study, we aimed to emulate the natural structure of nacre by synthesizing inorganic asperities and mineral bridges with different temperatures in the range of $1100-1300^{\circ}C$ and clay contents from 10 - 50 wt%. Following the infiltration of methyl methacrylate, we measured the mechanical properties to assess whether they were improved by the asperities. It was confirmed that the asperities improved the bending strength by 10%, and the anchoring effect was observed on the fracture surface.

수치해석을 이용한 연약지반에 시공된 스마트 앵커의 거동 분석 (Numerical Analysis of Smart Anchors in Soft Clay by)

  • 김낙경;김성규;강병철;김정열
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.964-968
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    • 2010
  • Ground anchor, commonly referred to as tiebacks or tie-down, is essentially steel elements secured in the ground by cement grout. They are used to provide either lateral or vertical support for various engineered structures, and are effective in all types of soil and rock. However, ground anchor can not be used in soft clay because anchor resistance would not be guaranteed. In this paper, conceptual introduction of the Smart Anchor is presented. The Smart Anchor is a kind of friction type anchor, the load is diffused and applied to the various parts of the distributed bond length, having less impact on the grout strength, and being able to secure necessary anchoring force in relatively soft grounds. This study shows a numerical study of predicting the load transfer of The Smart Anchor in soft clay. A beam-column analysis was performed by a elastic-plastic P-y curves in soft clay.

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