• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.71-72
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• 2010

The study is compared temperature history and strength of concrete followed by covering method of insulation curing of cold weather concrete with double bubble sheet. The results were as follows. First of all, in temperature history of concrete, the internal temperature of concrete fell down to $0^{\circ}C$ before/after 60 hours, having nothing to do with covering method. The study could see that, when sheet was isolated, it fell down to low temperature quickly in early curing. When the study measured compressive strength of core specimen, there were no large differences among placing methods. However, compressive strength fell down in all ages when sheet was isolated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.175-176
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• 2015

Insulation in buildings are one of the crucial factors for energy reduction, and depending on the application areas and properties of the insulation requirements, various different types of insulation materials are being developed, produced, and used. Amongst these is the aircaps often used as packing materials. Because of their porous nature, they are highly efficient in preventing heat and are consequently used overseas often as insulation materials and as part of cold water concrete insulation curing method. This paper studies the recently developed usage of aircaps in waterproofing materials and evaluated their performance as supplementary insulation materials.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.21-25
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• 2008

In this paper, the temperature history and the strength development of concrete corresponded to various bubble sheets layer and curing temperature. Based on the results, In case of the test temperature of -5℃, concrete subject in the exposure condition, result in a frost damage at initial stage by a fall of below zero temperature. In case of the combination of PE film and non woven fabric was after 36 hour, and combination of bubble sheet over double, a tremendous insulating effect of bubble sheet over double is confirmed due to the temperature of concrete fall of below zero temperature after 60 hours. Meanwhile, regarding the -15℃ of temperature, special measure for insulation curing is necessary to secure stability against early frost damage because frost damage was not affected by the lapping thickness of bubble sheet subjected to severe cold weather condition.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.85-90
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• 2012

In this study, temperature profile of the fly ash concrete were studied in accordance with the change of heating curing method combination for the slab concrete in order to develop efficient protection method of the concrete subjected to $-20^{\circ}C$. The slab concretes with the size of $1200mm{\times}600mm{\times}200mm$ were fabricated with W/B of 50% and exposed to $-20^{\circ}C$ for 7 days. Five different combinations of heat curing methods were applied to the slab concrete specimen; two combinations of heat supplying by electrical heater and surface heat insulation material such as polyethylene film and quadrupled layer bubble sheet based on heat enclosure installment; three combinations of heating coil embedment and surface heat insulation materials such as polyethylene film, sawdust and quadrupled layer bubble sheet based on heat enclosure installment. Test results showed that by applying both heating coil and bubble sheet and heat enclosure, the concrete exposed to $-20^{\circ}C$ can be effectively protected from early-age frost damage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.81-83
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• 2012

This paper is to compare the temperature history of the concrete using existing curing sheet and developed curing sheet made with double layered bubble sheet subjected to clod climate. Field application was conducted. According to results, application of developed curing sheet makes the temperature of curing house and concrete higher than existing curing sheet by about 3℃. This is due to the lower thermal conductivity of developed curing sheet.

• Journal of the Korea Institute of Building Construction
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• v.13 no.1
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• pp.38-47
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• 2013

When building with concrete in cold weather, an insulation method of heat curing must be determined, and a holistic curing plan that considers the characteristics of structures, the heat loss coefficient of a curing sheet, the joint condition of the curing materials and the quantity of heat produced by a heating apparatus is an essential prerequisite for protection against early frost damage. But on a number of national construction sites, there have been serious problems in cold weather concreting due to the unreliability of the information obtained from practical experience. In the construction field in Japan, there is a specification for heat curing prepared by Japanese Architectural Society, which provides an equation for calculating heat quantity. It is also necessary to adopt a detailed specification for a standard heat curing method that is applicable to all national construction sites. In this study, the effect of bubble sheets on the economic feasibility of cold weather concrete is investigated through a comparison with the blue sheets commonly prescribed in national construction sites. In conclusion, this study found that bubble sheets had the effect of reducing the cost of curing materials and the fuel cost consumed by a heating apparatus, compared to the use of blue sheets.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.913-918
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• 2001

This paper investigates insulating effects and strength properties of concrete under cold climate carrying out the experiment with insulating forms on the slab member. According to test results, under $-10^{\circ}C$ of outer temperature, the surface of concrete exposed to outer temperature goes below zero after 10hours since exposed. And, the surface of concrete covered with vinyl and blanket goes below zero after 42hours. However, the surface of concrete covered with insulating materials such as polystyrene foam does not drop below zero until 55hours. And, according to coring sample strength test, compressive strength cured with insulation shows much higher strength than no insulation curing condition and vinyl and blanket curing condition.

• Proceedings of the KIEE Conference
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• 1988.07a
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• pp.771-773
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• 1988

The Mechanical strength and the electrical insulation properties of the Epoxy Resin vary with the formation of chemical reactions between Epoxy and curing agent. Therefore, to study their reactions is important for understanding the properties of the cured Epoxy. In this paper, to get the cured Epoxy having good electrical insulation property, it is studied the effects of the surrounding temperature during the cure process on the property of the cured Epoxy. In the experiment, Epoxy is cured with the surrounding temperature varied between -5[$^{\circ}C$] to 50[$^{\circ}C$]. As the results, it follows that the higher the temperature is, the faster the cross-link process is.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.11a
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• pp.475-478
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• 1999

The thermal properties of epoxy resin/siloxane for the electrical insulation were investigated by using dynamic DSC run method. As the heating rate increased, the peak temperature on dynamic DSC curve increased. From the linear relation on the Kissinger plot the curing reaction activation energy and pre-exponential factor could be obtained. The curing activation energy from the straight line of the Kissinger plot was 46.72 kJ/mol.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.13-14
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• 2016

This study is aimed to analyze temperature history at each section of mat foundation concrete applying double bubble sheets. The results of the study are as follows. Firstly, the results of measuring the temperature history indicate that the lowest external temperature has been recorded at -5.6℃ for the three-day measurement period. For the central section, the result indicates that the lower, center and upper part have all secured the concrete curing temperature of 18℃ or higher. This results are believed to have resulted from excellent heat insulation performance of double bubble sheets. For the edge section between the edge form and the concrete interface, the temperature has been measured, on average, approximately 12℃ lower than the central section. However, all measured sections have indicated the temperature of 5℃ or higher. Meanwhile, an analysis has been conducted through the estimation equation of compressive strength of maturity during the curing period in order to examine the possibility of early frost damage and the aspect of securing strength. It has been confirmed that the compressive strength is higher than 50°D·D, namely, 5MPa, on the 3rd day of the aging process, which allows early frost damage to be avoided.