• 한국건축시공학회지
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• 제3권2호
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• pp.135-139
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• 2003

The purpose of this study is to analyze the curing effect of planar surface heater for concreting in cold weather. Some experiments were conducted to evaluate the temperature history of concrete cured with heating sheets in the laboratory conditions. As the results, It was showed that the 130W/$m^2$-heater could raise the inner temperature more than $20^{\circ}C$ under the environmental condition of -5~$-20^{\circ}C$. And the temperature of concrete cured by the 200W/$m^2$-heater was 5~$10^{\circ}C$ higher than that of concrete cured by 130W/$m^2$-heater. Finally, through the curing by the planar surface heater during the first 1.5~2 days, it is possible to secure the sufficient maturity of concrete.

• 한국농공학회지
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• 제13권4호
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• pp.2419-2425
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• 1971

한중(寒中)콘크리트 시공(施工)에 염화(鹽化)칼슘사용(使用)은 콘크리트의 초기강도(初期强度)를 최대한(最大限)으로 높여 동해(凍害)를 방지(防止)함과 경제적(經濟的인 구조물(構造物)을 만들고자 하는데 목적(目的)이 있으며 시험결과(試驗結果)로서 그의 범위(範圍)를 요약(要約)하면 다음과 같다. 1. 염화(鹽化)칼슘을 시멘트중량비(重量比) 1.5%를 TYPE I TYPE II에 혼합(混合)하면 초기강도(初期强度)를 최대한(最大限)으로 증진(增進)할 수 있고 구조물(構造物)의 안전(安全)을 위(爲)해서 1.5%내외(內外)가 적합(適合)하겠다. 2. 염화(鹽化)칼슘을 혼합(混合)하여 동결(凍結)의 위험(危險)을 방지(防止)하기 위한 콘크리트를 만들자면 w/c비(比)를 50% 내외(內外)로 정(定)해야 만이 한중(寒中)에 안전(安全)하겠다. 3. 포조란 초기강도(初期强度)는 떨어지나 후기강도(後期强度)가 점차(漸次)로 상승(上昇)한다. 4. 콘크리트의 초기강도(初期强度)의 증진(增進)으로 양생기간(養生期間)을 최대한(最大限)으로 단축(短縮)시킬 수 있으므로 콘크리트 구조물(構造物)의 끝손질을 조기(早期)에 실시(實施)해야 한다. 염화(鹽化)칼슘의 혼입(混入)은 시멘트응결(凝結)을 촉진(促進)시킬 수 있어 한중(寒中)에 있어서 동해(凍害)를 방지(防止)하고 공기(工期)를 최대한(最大限)으로 단축(短縮)시킬 목적(目的)으로 공사시공(工事施工) 현장(現場)에서는 유효히 사용(使用)될것으로 사료(思料)된다.

• 한국농공학회지
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• 제14권3호
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• pp.2677-2684
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• 1972

시멘트의결경화촉진(疑結硬化促進)으로 콘크리트의 초기압축강도(初期壓縮强度)를 얻음으로서 한중(寒中)콘크리트 공사시(工事時) 동해(冬害)를 예방(豫防)하고 보다 안전(安全)하게 구조물(構造物)을 축조(築造)하는데 도움을 얻고자 일반(一般) 포트랜드시멘트(TYPE I) 조강(早强)시멘트(TYPE II) 및 포조란시멘트를 사용(使用)하여 본시험(本試驗)을 실시(實施)한 것이다. 이상(以上)의 결과(結果)를 요약(要約)하면 다음과 같다. 1. 보통(普通)포트랜드시멘트(TYPE I) 보다 조강(早强)시멘트(TYPE II)가 초기강도(初期强度)가 높았고, 2. 조강(早强)시멘트로 만든 콘크리트 초기강도(初期强度)의 증진(增進)으로 공기(工期)를 최대한(最大限)으로 단축(短縮)시킬수 있어 한중(寒中)콘크리트 공사시공(工事施工)에 적합(適合)하겠다. 3. 조강(早强) 및 포조란은 높은 분말도(粉末度)로 외기(外氣)에 대(對)한 풍화작용(風化作用)이 촉진(促進)될 우려(憂慮)가 있으므로 저장기간(貯藏期間)이 짧아야 하겠다. 4. 국내(國內)에서 생산(生産)되는 포조란시멘트가 조강현상(早强現象)을 나타냄으로 이에 대(對)한 시험(試驗)이 계속 필요(必要)하겠다. 이상(以上)의 결과(結果)는 공사현장(工事現場)에서 유효하게 적용(適用)될 것으로 믿는다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.647-650
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• 2001

The purpose of this study was the influence of cold weather ready mixed concrete quality according to needs of customer were investigated by measurements of slump, air content, temperature and compressive strength. As a results, cold weather ready mixed concrete using high standard admixtures, high early strength admixtures and cold weather concrete plant were similarly to slump, air content, temperature and compressive strength.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 춘계 학술논문 발표대회
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• pp.67-68
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• 2013

In this paper, the compressive strength of an insulating gang form member, which was developed to improve the cold weather concreting quality, and a general gang form member was measured by age to examine the compressive strength characteristics of the two members compared with the standard curing test piece.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.17-20
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• 2005

This paper reported the temperature history of concrete placed at deck plate slab under cold climate condition by varying with surface insulating type. No curing sheet and simple insulation curing including non-woven fabric, double layer bubble sheet, the combination of double layer bubble sheet and non-woven fabric dropped temperature below zero within 24 hours, which caused frost damage at early age. On the other hand, the combination of double layer bubble sheet and non-woven fabric and double layer bubble sheet and styrofoam maintained minimum temperature above $4^{\circ}C\;and\;8^{\circ}C$, respectively. Based on core test results compressive strength of concrete with the combination of double layer bubble sheet and non-woven fabric and double layer bubble sheet and styrofoam was higher than those with other curing method due to good insulation effect.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 추계 학술논문 발표대회
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• pp.25-28
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• 2005

This study investigates the field application of surface insulation curing method, which combined double layer bubble sheet(DBS) and thick-curing-material(TCM) for cold weather concreting. According to the test, deck slab, curing only upper section with DBS and TCM, does not make big different temperature history with that, curing both upper and bottom section during daily average temperature 6.5t. It is concluded that combination of DBS and TCM in only upper section can be safely cured in early period of time during cold water concreting. The field test was carried out with this favourable data. The upper deck slab was insulated by combination of DBS and TCM, and the construction was surrounded by tent. in order to protect from outside wind. The test result shows that the lowest temperature of deck slab indicated 6$ ^{circ}C $. It demonstrated that this curing method can resist early frost and save construction cost in the side of management and saving labor cost, compared with previous method. In addition, the column specimen, combined both form and bubble board, exhibited favorable temperature history, due to internal hydration heat insulation effect.

• 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.

• 한국건축시공학회지
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• 제3권4호
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• pp.87-94
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• 2003

This study is to investigate the temperature hysteresis and development of compressive strength due to the curing conditions and to evaluate the optimum curing condition of test specimens showing the same development of strength to that of real structures in cold weather. The results of temperature curve with curing conditions in mock-up tests showed the trend of decrease plain concrete with insulation form, plain concrete with heating, concrete with accelerator for freeze protection, and control concrete in turn. The strength development of plain concrete of inside and outside of shelter showed the very slow strength gains due to early freezing, but that of concrete with accelerator for freeze protection showed the gradual increase of strength with time. From this, it is clear that accelerator for freeze protection has the effects of refusing the freezing temperature and accelerating the hardening under low temperature. Strength test results of small specimens embedded in members and located in insulation boxes at the site are similar to that of cores drilled from the members at the same ages, thus it is clear that these curing methods are effective for evaluating in-place concrete strength

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 춘계 학술논문 발표대회 학계
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• pp.25-28
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• 2009

This study investigated the results of insulation heat curing method using double layer bubble sheet in slab 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 5 and $l0^{\circ}C$ even in case outside temperature drops $-11^{\circ}C$ below zero until the 4nd 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.