• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.71-72
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• 2014

Green Frame is a building frame system to construct a column-beam structure using composite precast concrete members. To reduce the cost of producing precast concrete, in-situ production of members is required. However, when the structural members are produced on site, it needs a large space for production. So, "Just-In-Time" production method should be adopted. For Just-In-Time to be realized, the early strength of members should be ensured for them to be transported. Thus, steam curing to secure the early strength is applied in Green Frame. Yet, a large-scale steam curing system is not possible for in-situ production of precast concrete. A smaller steam curing system is needed. In this regard, the study is aimed to develop a new steam curing method applicable to the in-situ production of precast concrete.

• 마이크로전자및패키징학회지
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• 제21권4호
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• pp.51-56
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• 2014

가격적 경쟁력을 가지는 Ag 코팅 Cu 플레이크 함유 도전성 페이스트를 제조하여 경화조건에 따른 열전도도 및 전기전도도 값의 변화를 측정하였다. 대기 중에서 경화시킨 시편의 경우 경화시간이 30분에서 60분으로 증가됨에 따라 열전도도가 증가하는 경향이 관찰되었다. 60분의 동일한 경화시간 조건에서는 질소 중 경화 시편이 대기 중 경화 시편보다 향상된 열전도도 값을 나타내었다. 그 결과 질소 중에서 60분간 경화시킨 Ag 코팅 Cu 플레이크 페이스트는 순수 Ag 플레이크가 함유된 페이스트가 나타내는 열전도도에 근접하는 열특성을 나타내었다. 한편 대기 중 경화 시편의 경우 경화시간이 30분에서 60분으로 증가됨에 따라 비저항 값이 더욱 증가하는 경향이 관찰되었나, 60분의 동일한 경화시간 조건에서 질소 중 경화 시편은 대기 중 경화 시편에 비할 수 없을 만큼 개선된 비저항 값($7.59{\times}10^{-5}{\Omega}{\cdot}cm$)을 나타내었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.553-556
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• 2003

This study is analyzed about the factor of adhesive strength characteristics, curing time, asphalt application, test temperature which are liquid waterproofing membrane of rubber-asphalt and chloroprene-rubber type for concrete bridge deck. According to the results, curing time is shorter, adhesive strength is less in chloroprene-rubber type. And also chloroprene-rubber and rubber-asphalt type are showed high adhesive strength in low temperature.

• 한국농공학회논문집
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• 제53권5호
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• pp.25-33
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• 2011

In this paper, the effects of aggregate and curing temperature on strength development characteristics of UP (Unsaturated Polyester)-MMA (Methyl Methacrylate) based polymer mortar under sub-zero temperature are experimentally investigated to provide a criterion for repair and production of precast products. The result showed that the setting time of the binder was 4 minutes at $20^{\circ}C$ whereas 35 minutes at $-20^{\circ}C$. The result also revealed that the compressive, flexural, and splitting tensile strengths of UP-MMA based polymer mortar significantly decreased as the aggregate and curing temperatures decreased. However, sufficient strengths which can be implemented in actual practices -36.6 MPa of compressive strength, 6.11 MPa of flexural strength, and 5.81 MPa of splitting tensile strength - were obtained even though both aggregate and curing temperatures were $-20^{\circ}C$. Strength development of polymer mortar is largely affected by curing temperature rather than aggregate temperature. It was found that the effects of aggregate temperature on strength development become smaller as the curing temperature becomes lower. Also, toughness, a ratio of compressive strength to flexural strength, increased from 3.5 to 5.9 as both aggregate and curing temperatures decreased from $20^{\circ}C$ to $-20^{\circ}C$.

• International Journal of Concrete Structures and Materials
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• 제9권4호
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• pp.487-498
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• 2015

A proper initial curing is a very simple and inexpensive alternative to improve concrete cover quality and accordingly extend the service life of reinforced concrete structures exposed to aggressive species. A current study investigates the effect of wet curing duration on chloride penetration in plain and blended cement concretes which subjected to tidal exposure condition in south of Iran for 5 years. The results show that wet curing extension preserves concrete against high rate of chloride penetration at early ages and decreases the difference between initial and long-term diffusion coefficients due to improvement of concrete cover quality. But, as the length of exposure period to marine environment increased the effects of initial wet curing became less pronounced. Furthermore, a relationship is developed between wet curing time and diffusion coefficient at early ages and the effect of curing length on time-to-corrosion initiation of concrete is addressed.

• 대한토목학회논문집
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• 제35권2호
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• pp.465-470
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• 2015

에폭시 아스팔트 혼합물은 에폭시 수지와 경화제의 화학반응이 진행되어 양생시간을 거쳐 성능 발현이 이루어진다. 에폭시 아스팔트의 양생수준은 후속공정의 진행과 교통개방 및 공정계획의 수립에 절대적인 영향을 미치므로 정확한 예측모델의 개발이 중요하다. 본 연구에서는 기존 예측식에 사용되는 인자들의 화학적 의미 분석을 통하여 에폭시 수지의 농도와 경화특성을 반영하여 기존식보다 확대된 적용 범위를 갖는 양생수준 예측식을 제시하였다. 실외양생 실험과 비교 결과 상관계수가 0.971 이상으로 나타나 조성이 다른 에폭시 아스팔트 혼합물의 온도와 시간에 따른 양생수준을 예측할 수 있는 것으로 나타났다.

• 펄프종이기술
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• 제34권4호
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• pp.16-21
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• 2002

It was observed that drying temperature and curing time in the paper coating process as well as Tg of the latex used as a binder, greatly affected the properties of the coated paper such as roughness, paper and print gloss, K & N ink drop, and ink set-off. The higher drying temperature induced faster water evaporation and change in binding density, which caused an increase in paper roughness, ink gloss and ink set-off, but decrease in paper gloss and K & N ink drop. The increased curing time promoted latex filming and redistribution of the binder in coating layer. This increased pick strength and ink gloss, but decreased ink trapping. Finally, the higher Tg of the latex showed the wider changing range of these properties.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1996년도 춘계학술대회 논문집
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• pp.260-263
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• 1996

The thermally stimulated currents(TSC) are measured to know the behaviour of charging particles of epoxy composites at the temperature range of -160∼200[$^{\circ}C$] and to prove the variation according to curing time in this study. It is confirmed that the peak amplitude is inversely proportional to the curing time, and TSC are reduced is and T$\sub$m/ is moved to high temperature side according to the curing time because carboxyl radical is formed by thermal oxidation and motility becomes lack.

• 한국추진공학회지
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• 제12권4호
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• pp.24-32
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• 2008

항력감소제 추진제의 경화시간을 단축하여 생산성을 향상시키고자 새로운 추진제 조성을 개발하였다. 신규로 개발된 추진제 조성에 대한 바인더 특성 및 공정성 확인시험을 수행하였으며 아울러 다양한 추진제의 기본특성 및 최종 성능시험을 수행하였다. 시험결과, 모든 시험 항목들이 요구된 조건들을 만족하였을 뿐만 아니라 경화시간도 약 53% 단축되어 생산성 향상에 기여되었다.

• 접착 및 계면
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• 제13권2호
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• pp.85-88
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• 2012

In this paper, the curing reaction of UF resins was investigated by a real time FT-IR method. The curing temperature range of the UF resin was $25{\sim}200^{\circ}C$. It was found that the reactions of UF resin at different temperatures resultedin resins with different cross-linked structures. A real time FT-IR spectroscopy can be considered as a good routine analytical tool for following the progress of UF resin curing.