• Journal of the Korean Society of Tobacco Science
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• v.2 no.1
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• pp.61-67
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• 1980

The greenhouse hulk curing and drying system utilizing the direct solar energy was tested to see how much fuel could be saved for curing flue-cured tobacco at the Daegu Experiment Station, Korea Tobacco Research Institute (North latitute: 35$^{\circ}$49'), in 1979. The structure consists of transparent fiberglass exterior, polyurethan boards covered with galvanized iron as the heat absorbers and insulation boards, air duct in which the air is introduced to the furnace room of bulk curing barn, and gravel heat storage system. All exterior surface of heat absorbers, air duct, and gravels were coated with black paint. The air temperature and total radiation were 20.5 to 35.5$^{\circ}C$ and 1004.2 to 1436.2 cal/$\textrm{cm}^2$ during the 3 replicated curing tests, respectively. The greenhouse bulk curing and drying system was able to cut fuel consumption by 25 percent compared with the conventional bulk curing barn. The maximum temperatures for the top absorber and the inlet air of the system were 89$^{\circ}C$ and 64$^{\circ}C$, respectively, and the average temperature of inlet air was higher than that of conventional one by 18$^{\circ}C$.

• 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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• 2006.05a
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• pp.15-18
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• 2006

The test result of mat concrete applying both hydration heat difference and insulation curing method on new construction of Cheongju university educational building are summarized as following. Both fresh concrete and compressive strength properties were satisfied In aimed value. Setting time of concrete incorporating 15% of fly ash(FA) retarded 1.2 hour than control concrete. Temperature history of mali concrete indicated that the highest temperature of center was exhibited at $126^{\circ}C$ after 51 hours while the highest temperature of upper section was $10.6^{\circ}C$ after 46 hours. Temperature Difference between center and surface was managed at less than $6^{\circ}C$ during whole curing period. In addition the temperature of upper section secured more than $3.3^{\circ}C$ while the temperature of outside was indicated at less than $-10^{\circ}C$. Maturity by parts of construction secured more than $30^{\circ}C$ DD higher than outside at 3 days. The more number of times, applying insulation curing method by double bubble sheets, increased, the higher economic effect was secured. Overall it was clear that applying both double bubble sheets and hydration heat difference method on this new construction can resist hydration heat crack, early frost demage and strength decrease. It also significantly contributed quality improvement of cold weather concreting

• 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.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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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.

• 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.

• Composites Research
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• v.34 no.1
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• pp.57-62
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• 2021

As interest in the eco-friendly ships and lightweight equipment is increasing in the shipbuilding and marine industry, composite materials are applied to equipment such as pipes. In this study, a basalt fiber reinforced furan composite (BFC), an eco-friendly material, was manufactured to apply the pipe insulation cover that requires environment-friendly and heat/flame retardant performance. An optimization study of post-curing conditions of BFC was conducted, and experiments and analysis were performed on mechanical strength, heat/flame retardant properties, and affinity properties. Finally, as a result of the study BFC material is proved to be a good candidate to apply pipe insulation cover.

• Journal of the Korean Graphic Arts Communication Society
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• v.22 no.1
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• pp.83-94
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• 2004

PSR ink is used to insulation coating material that heat resistance is. The use purpose is used for bridge prevention, circuit protection, stabilization of insulation. Heat-cured resin was used mainly on the materials of PSR inks. But, UV-curing type resin in used. Also, because of recently environmental problem, ink is going to water type. Purpose of this study is to develop PSR ink that can develop in pure water. and experiment did that do from that find suitable oligomer and monomer and does brand ratio differ. Specially Knew that is extent water soluble UV resin develop possible is DPHA 10~50% that A/A1924 is 50~90wt %, monomer. As a result, when ratio of A/A1924 and DPHA low viscosity epoxy resin is 5:1.5:1.5, could get high sensibility pattern repeatability, tack and alkali-resistance.

• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.121-128
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• 2010

The present research examined heat insulation performance according to change of various laid construction conditions of double bubble sheet being used as material for heat insulation & curing construction of cold weather concrete, and its results are as follows. First, the change in a laid period of bubble sheet within 4 hours and the change in water content inside bubble sheet overall showed similar temperature history and maturity without a big difference in terms of the temperature history of concrete according to construction factors, but it could be confirmed that when a structure was thin or several bubble sheets are laid, requisites unfavorable for initial curing of concrete can occur if a lagger distance between sheets is generated. In terms of the compressive strength of concrete core specimens, it appeared that the initial compressive strength is declined when conditions unfavorable for concrete curing such as delay of a laid period of bubble sheets, induction of large distance between sheets, increase of water content inside bubble sheets and thinness of a structure of placing concrete, etc. were applied, but it appeared that as its age passes, the difference becomes small.

• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.67-76
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• 2016

Concrete exposed to severely low temperature below $-20^{\circ}C$ should be provided with proper heat supplying curing to protect the concrete from early frost damage at the time of pouring.meanwhile, so far, effective heat curingmethods of the concrete under severely low temperature are not well established in Korea. For this reason, the objective of this paper is to provide effective heat curingmethod of concrete exposed to severely low temperature to protect early frost damage by varying the combination of heat curingmaterial combinations. Temperature history,maturity development and core strength results are investigated. Fourmock-up specimens simulating slab, wall and column were prepared and heat insulation, heat supplying and both were applied. Test results indicate that the combination of quadruple layer bubble sheet(4BS) and embedding of heating cable has desirable performance for a slab, and heat supplying curing inside heat enclosure and heat generationmat also shows desirable performance for a wall, and for a column, use of EPS heat insulation has proper performance against early frost damage, which reaches $45^{\circ}D{\cdot}D$ and helps the concretemaintain above $0^{\circ}C$ within 3 days. Themethodsmentioned above are believed to be optimum protection from early frost damage of the concrete under $-20^{\circ}C$.