• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
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• pp.408-413
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• 1996

The purpose of this study is to present the reference data about the period in cold weather concrete practice based on meteorological data of Korea meteorological administration in our country in comparison with previous study and specifications of foreign country as to cold weather concrete such as ACI, JASS-5 and JSCE. The results of this study indicate that the period of cold weather concrete by each specifications in most of the region except Cheju island and coastal region in Korea is lasted over 100 days and the period of cold weather concrete in hillsides and inland areas is longer than that of coastal regions in the same latitude.

• 콘크리트학회논문집
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• 제17권2호
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• pp.237-245
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• 2005

본 연구에서는 우리나라 기상청의 기온자료를 이용하여 시간변화에 따른 각 지역의 한중콘크리트 적용기간을 KCI, ACI 및 AIJ 방법에 따라 산정한 후 동방법의 기존연구결과와 비교 분석함으로써 시간변화에 따른 한중콘크리트 적용기간의 변화를 분석하고자 하였다. 연구결과에 따르면, KCI에 의한 적용기간은 평균 9.5순으로 나타났고, ACI에 의한 적용기간은 10.1순 그리고 AIJ에 의한 적용기간은 9.2순으로 산정되었다. 시간변화에 따른 적용기간으로서 KCI 및 ACI 규정에 의한 본연구의 적용기간은 10년전의 종전 연구보다 약 5${\~}$6일 정도 짧아진 것으로 확인되었으나, AIJ 규정에 의한 적용기간은 종전의 연구와 거의 차이가 없었고, 단, 김의 연구와 비교할 경우 약 3일 정도 짧아지는 것으로 나타났다. 한편, 지역별로는 남부지방의 경우 종전연구에 비하여 한중콘크리트 적용기간이 비교적 많이 단축되었는데,. 이는 지구의 온난화에 의한 평균기온의 상승으로 인한 것으로 사료된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.326-328
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• 2013

This study compares the periods of cold weather concrete determined by the codes regulated by KCI (Korean Concrete Institute) and AIJ (Architectural Institute of Japan). For the calculation of the periods of cold weather concrete, the climate data for last 5 years obtained from Korean weather forecast station is used. Calculated data indicated that the period of cold weather concrete by AIJ code is longer than that by KCI code. Although global warming causes the decrease of the period of winter season, the temperature differences are large in Korea. Therefore, it is required that the current KCI code should be accordingly upgraded to reflect the weather variation in Korea over time.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.261-264
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• 2003

Cold weather can lead to many problems in mixing, placing, setting time, and curing of concrete that can have harmful effects on its properties and service life. Korean Concrete Institute (KCI) defines cold weather as a period when the average daily air temperature is less $4^{\circ}C$ and recommends to cast concrete with special care such as shielding, heating and so on. The use of high early strength cements may improve the rate of hardening characteristics of concrete in cold weather by making it possible to achieve faster setting time and evolving more hydration heat than ordinary Portland cement. Higher early strength can be achieved using Type III cement especially during the first 7 days. The strength increase property of Type III cement at low temperature was studied. As a conclusion the heat or heat insulation curing period can be reduced to 50~75%. So, it can be used for cold weather concreting to reduce construction cost and extend the construction season.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 가을학술발표대회논문집
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• pp.57-58
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• 2023

This study is to estimate cold weather concrete periods by analyzing data of Korea Meteorological Administration in terms of recently revised cold weather concrete regulation of Korea Concrete Institute.

• 한국건축시공학회지
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• 제17권1호
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• pp.73-81
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• 2017

본 연구는 기상자료를 토대로 우리나라 각 지역별 한중 콘크리트 적용기간을 KCI 및 AIJ 규정에 의한 방법으로 각각 산정하고 초기동해 위험일을 각 지역 및 온도 단계별로 제안하고자 하였다. 한중 콘크리트 적용기간의 경우 최근 5년간의 기상자료를 토대로 조사한 결과와 종전의 연구결과를 비교하였다. 연구결과에 따르면 국내 91개 지역의 한중 콘크리트 적용기간은 평균 98일로 조사되었고, 고위도 지역일수록, 산악 및 내륙지역일수록 적용기간은 증가되는 것으로 나타났으며, 종전 연구 대비 본 연구의 적용기간이 1~2일 정도 감소되는 것으로 나타났다. 지구온난화, 도시화 등의 영향으로 판단된다. 초기동해 위험일의 경우 $-5^{\circ}C$, $-2^{\circ}C$ 및 $0^{\circ}C$ 단계별로 시작일 및 종료일을 제시하였으며, 이를 토대로 $0^{\circ}C$ 이하 출현일 수, 출현일 및 평균 추위도를 제시하였다. 본 연구 범위에서 제시된 초기동해 위험일은 KCI에 의한 한중콘크리트 적용기간보다 길게 나타난 지역이 다수 존재하여 한중콘크리트 적용기간 이외에도 초기동해 위험이 있음을 확인할 수 있었다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 추계 학술논문 발표대회
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• pp.53-56
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• 2008

This paper is to investigate the change of the period of hot weather concrete with elapse of age based on climate data. Climate data for 30 years and 5 years are used respectively. Determination of the period of hot weather concreting on architectural execution in Korea according to the specifications of AIJ, KSCE, and ACI are discussed. According to the research, the period of hot weather concreting with each specification in most regions lasts over 35 days. Compared with the period of cold weather concreting in hillside and inland area, coastal areas have shorter period in the same latitude. The period of hot weather concreting tends to decrease with high latitude. As expected, with the elapse of age, the period of hot weather concrete exhibited to decrease, especially, big city like Seoul, Busan etc had remarkably increased period by as much as a week. This is due to the global warming and industrialization effect with the elapse of age.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.21-23
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• 2010

This study was conducted to draw various decisive elements of a reasonable heat curing method and to examine the importance in deciding a construction method when constructing cold weather concrete. As a result, the items proposed as important elements at the time of decision of a heat curing method included economy, workability, maintainability, insulation capability, reduced construction period and usability. As a result of importance by items under AHP technique, it was found the most important element was insulation capability, followed by reduced construction period and workability. As a result of comparison of a heat supplying and a heat insulation method by dual bubble sheet differed 2 times as much as a heat supplying method, especially the evaluation degree by insulation capability and reduced construction period was high.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2008년도 춘계 학술논문 발표대회
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• pp.57-60
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• 2008

This study investigated the results of insulation heat curing method using double layer bubble sheet in slab concrete and mass concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that slab concrete was protected from early freezing by remaining between 6 and 15℃ even in case outside temperature drops -9℃ below zero until the 2nd day from piling, and in the case of mass concrete, with the maximum temperature difference between the center and surface less than 4℃, crack occurrence index was close to 2 and no hydration heat crack occurred by internal constraint. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 춘계 학술논문 발표대회 1부
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• pp.83-85
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• 2011

This study investigated the results of insulation heat curing method using double layer bubble sheet in concrete in cold weather environment. First of all, when double bubble sheets are applied, it was shown that concrete was protected from early freezing by remaining between 7℃ and 3℃ even in case outside temperature drops -7℃ below zero until the 3d day from piling. The insulation heat preservation curing method using the double bubble sheet applied in this field prevented early freezing owing to stable curing temperature management, deterring concrete strength development delay at low temperature, and obtained the needed strength. Also, it was proven that the method is highly effective and economic for cold weather concrete quality maintenance through curing cost reduction like construction period shortening and labor cost reduction, etc by reducing the process of temporary equipment installation and disassembling.