• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.45-49
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• 1978

Sericin 정착은 친수성 단백질인 세리신을 화학처리에 의하여 소수성으로 변화시켜 fibroin 에 밀착, 응고시켜 생사를 양모와 유사한 섬유로 변화시켜 제품의 다양화를 기할 목적으로 많이 행하여졌으며 이에 따른 증량효과도 크게 기대되어진다. 종래의 세리신 정착방법들은 생사의 제리신 정착외에 공업적으로 그 가치가 크게 인정되었던 견사, 생사 층 등에도 광범위하게 응용되어 많은 특허가 있는데 이들 정착방법을 대별하면 (1) Aldehyde 처리에 의한 세리신 정착 (2) Cr 감류처리에 의한 세리신 정착 (3) Epoxy 화합물의 처리에 의한 세리신 정착 (4) 합성수지 처리에 의한 세리신 정착등을 들 수 있겠으며 그 중에서도 특히 Aldehyde 에 의한 정착 (주로 formaldehyde 사용) 과 Cr 감류에 의한 정착이 가장 많이 행해진 경향을 보인다. (중략)

• Journal of Sericultural and Entomological Science
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• v.37 no.2
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• pp.137-141
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• 1995

The sericin fixation of raw silk by glutaraldehyde solutions with catalyst(serifix B) was done and the effect of sericin fixation by catalyst on reaction mechanism, whiteness and physical properties were investigated and discussed. The obtained results were summarized as follows; 1) The complete sericin fixation were obtained by glutaraldyhyde solution regardless the concentration of catalyst. 2) The tenacities of sericin fixed silk increased in comparison with that of nontreated silk. 3) There were not constant tendency in elongation of sericin fixed silk in comparison with nontreated silk. 4) The whiteness of sericin fixed silk treated glutaral-silk in comparison with nontreated silk. 5) FT-IR spectra were quite different from sericin fixed reagent and catalyst.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.143-146
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• 2005

최근 들어 90도 표준갈고리의 대안으로 정착판을 지니는 헤드 철근(headed bar)에 대한 관심이 높아지고 있다. 헤드 철근의 정착내력은, 정착판의 지압력과 위험단면에서 헤드까지 정착길이의 부착력으로 발현된다. 실제 구조물에서는 정착되는 부재의 재료 및 기하학적 물성에 의해 다양한 파괴가 발생된다. 따라서 헤드 철근의 정착내력은 단순히 지압력과 부착력의 합으로 산정될 수 없으며, 발생 가능한 모든 파괴양상을 고려한 최소 내력으로 결정되어야 한다. 헤드 철근의 정착내력을 산정하기 위한 기본적인 해석모델로, CCT 절점에 정착된 헤드 철근의 트러스 모델을 제안하였다. 제안된 트러스 모델의 파괴는 부착파괴와 콘크리트의 압축파괴로 구분되며, 재료 및 기하학적 물성에 의해 파괴 양상이 결정된다. 이러한 트러스 모델은 외부 보-기둥 접합부와 같이 보다 복잡한 부위에 정착된 헤드철근의 정착 기구를 설명하는데 활용될 수 있다.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.3-12
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• 2015

Bursting stress in anchorage zone of post tension girder can be estimated based on Guyon's equation. The major parameters in calculating bursting stress are prestressing force and the distance ratio between concrete edge and anchorage plate. Although Guyon's equation can be applied to calculate bursting stress for rectangular typed as well as circular typed plate, there is some limitation of accuracy due to 2 dimensional analysis. Therefore this study is proposed to suggest a bursting stress equation based on 3 dimensional finite element method.

• Journal of the Korea Concrete Institute
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• v.13 no.6
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• pp.593-601
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• 2001

In RC structure, sufficient anchorage of reinforcement is necessary for the member to produce the full strength. Generally, conventional standard hook is used for the reinforcement's anchorage. However, the use of standard hook results in steel congestion, making fabrication and construction difficult. Mechanical anchor offers a potential solution to these problems and may also ease fabrication, construction and concrete placement. In this paper, the required characteristics and the design considerations of mechanical anchor were studied. Also, the mechanical anchor was designed according to the requirements. To investigate the pull-out behavior and properness of mechanical anchorage, pull-out tests were performed. The parameters of tests were embedment length, diameter of reinforcement, concrete compressive strength, and spacing of reinforcements. The strengths of mechanical anchor were consistent with the predictions by CCD method. The slip between mechanical anchor and concrete could be controlled under 0.2mm. Therefore, the mechanical anchor with adequate embedment could be used for reinforcement's anchorage. However, it was observed that the strength of mechanical anchors with short spacing of reinforcements was greatly reduced. To apply the mechanical anchor in practice (e.g. anchorage of the beams reinforcements in beam-column joint), other effects that affect the mechanical anchor mechanism, such as confinement effect of adjacent member from frame action or effects of shear reinforcement, should be considered.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.169-172
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• 2008

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 mold-type anchorage system for prestressed CFRP laminates through experimental study. The experimental parameters were the type of anchorage detail and the effect of surface treatment. The test results showed that the developed anchor assures 100% CFRP laminate strength.

• Land and Housing Review
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• v.2 no.1
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• pp.53-60
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• 2011

In this study, development tests varying with concrete strength, development length, and the rate of fiber mix ratio are carried out to evaluate the development characteristics of high-strength concrete member with 80MPa, and the applicability of estimated standards of development length in KCI 2007. As a result, it can be expected that minimum development length of KCI 2007 is applicable to high-strength concrete member with 80MPa. Although the mixed fiber(NY+PP) to secure fire resistance performance of high-strength concrete is included up to 0.1%, it does not affect the development characteristics.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.321-324
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• 2008

This paper presents the results of the performance of compression-type anchor for CFRP tendon. As the results of previous tests, the principal variables for enhancing performance of anchor were sleeve dimensions, inserts, compression pressure, etc. A total of 18 specimens were tested for the performance of compression-type anchor with various inner shapes. Test results revealed that the length of sleeve increased along with the performance of anchor up to 18-22%. Also, the performance of anchor was susceptible to the length of sleeve compared to the surface treatment with the oxide.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.2
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• pp.412-417
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• 2009

In order to investigate the effective sericin fixation of raw silk fibers the influence of various additives added to the melamine and formalin mixtures on sericin fixation was studied. When raw silk fibers were treated with wetting agent but without subsequent washing before sericin fixation, the strong sericin fixation was obtained by fixing sericin. Adding hydrogen peroxide to the melamine and formalin mixture made sericin fixation worse, resulting weaken the sericin hardness of fixed raw silk fibers and tight bonding of the fibers. On the other hand, it was confirmed that adding sodium hydrosulfite to the melamine and formalin mixtures gave better sericin hardness of fixed raw silk fibers without the bonding of fibers. Supplying additional melamine with he low concentration of sodium hydroxide to the melamine and formalin mixture(melamine:formalin= 1:6) resulted in very good sericin fixation. But adding hydrochloric acid or methanol to the same mixture had no effect on the sericin fixation, and adding magnesium chloride to it made the hardness of sericin fixation even worse.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.73-83
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• 2016

Bearing stress near anchor plates is usually very high due to prestressing force in anchorage zone of concrete structure used post-tensioned prestressed method. In order to effective utilization of cross section and crack control, appropriate size of anchorage plates should be used to prevent crack initiation and failure of concrete structures eventually. This study aims to suggest equation for effective area of bearing plate of rectangle type and circular type by Highway Bridge Design Specification and PTI etc. A shape factor according to bearing plate shape is suggested based on numerical analysis, and it can be used suitability for design of special anchorage plate dimension.