• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.29-32
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• 2006

Experimental test results of field construction, Cheongju University Educational Liberal Art Building, applying the insulating curing method on slab concrete showed that the quality of concrete in fresh and hardened state satisfied all target values. Temperature history of slab concrete in A and B area secured more than $7.8{\sim}9.2^{\circ}C$ higher than outside atmosphere. After completing certain curing period of time on the surface of the structure, crack occurrence was not found. It is concluded that the preventing vaporization of moisture by the insulating curing method reduces plastic and drying shrinkage as welt as improves durability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.05a
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• pp.67-71
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• 2008

The study analyzed on fire resistance of high strength concrete followed by thickness of fireproof plaster board and change of adhesive method. In spalling characteristics after fire resistance test, all four-side covering concretes were left out of testing screens. Thus, serious spalling was happened by exposing their internal reinforcing rods. in partial testing screens, spalling was happened till the internal concrete of main reinforcing rod. Only, temperature history didn't have special differences among changes of adhesive method. However, thickness of fireproof plaster board is very important. Namely, mock member reinforcing 25mm general adhesive + Bending was 583℃ in the highest temperature of surface part and 479℃ in the highest temperature of the main reinforcing rod, which was relatively good temperature history.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.113-114
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• 2013

This study is to investigate the effect of the diameter of reinforcement bars located in an aluminum-form on the temperature histories of the re-bars before placing concrete during a cold weather condition. The diameters of reinforcement bars with 13 mm, 19 mm, 25 mm and 32 mm were prepared for the experimental tests. Results showed that the larger the size of the diameter of the bars, the higher were the temperature drop. However, this study found that its effect on the temperature drop of the bars was insignificant.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.75-77
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• 2013

In this study, the characteristics of temperature history was evaluated for three hot wires with different capacity installed in slab concrete which are relatively thin. Results can be summarized as follows. First, for the case of material using 5W hot wire, all decreased to below zero at or around 24 hours. Similarly, the material using 20W hot wire decreased to 2℃ below zero at or around 80 hours but satisfied the accumulative temperature of 45° D·D at 7 days of material age. On the other hand, the case of 30W hot wire, the biggest capacity, showed the high temperature history of 5℃ in average at all areas except the corners. Thus, the target accumulative temperature was secured at or around the 3 days of material age. Considering the above, the initial damage by freezing can be prevented only if 20W or higher hot wires are used for the slabs at -10℃ of extremely low temperature environment.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.05a
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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.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.663-668
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• 2002

In this paper, insulating effects and strength development of concrete placed at mock up model structure are discussed using anti freezing agent and insulating forms. According to test results, concrete containing 8% of anti freezing agent shows lower freezing temperature, earlier setting time and higher strength development than plain concrete. As for the temperature history of mock up structures, when plain concrete is placed at euro form, the temperature drops to -4${\circ}$ before early 24 hours, and when concrete containing anti freeze agent at euro form, it to -3${\circ}$ before early 24 hours. Nevertheless, when concrete containing anti freeze agent is placed at insulating form, it does not go below zero, and the concrete containing anti freeze agent enhances higher strength development.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.351-354
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• 2005

Quality of concrete required to achieve the desired levels of strength and durability depend on the effectiveness of the curing method. During cold weather, the concrete at the time of placement should be taken to prevent damage to concrete due to freezing. Since the cement-water reaction is exothermic by nature, the temperature within mass concrete can be quite high. The temperature control for massive sections should be taken more careful than for shallow sections. However, in the constructing hydraulic structures, the curing temperature control for concrete had been very difficult to be taken in a proper way because the conditions constructing them are poor and contractors are small enterprises. For several. reasons including above, Rural Research Institute has developed a device and program for recording curing temperature history in cold weather concrete and mass. As there are two major advantages of the device, namely cheapness and availability, this program and device has been recommended to the use of curing temperature control in cold weather concrete and mass.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.89-92
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• 2005

Our country has experienced variations in temperature as belong to the area of the continental climate that shows four significant seasons. These occur quality of construction. As the hydration of cement processes, the strength of concrete is developed. In order to improve the quality of concrete, various conditions including temperature and humidity should be maintained appropriately and concrete itself should be cured sufficiently This paper is basic experiment for estimating influence of strength by seasonal mock-up concrete's heat of hydration and estimate relationship of compressive strength development by curing temperature. And show basic document as quality control.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.207-208
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• 2017

The current study assumed a condition in which concrete curing was not completed correctly in the winter, in order to analyze the effect of changes in early low-temperatures in early-frost damage depth. As a result, lower external temperature early on after depositing the concrete greatly reduced the temperature in the upper parts of the concrete, and it delayed the time during which the concrete temperature restored. In addition, for early-frost damages, lower early temperature increased the expansion of frozen water, which in turn relaxes the concrete structures and increases the absorption rate, ultimately extending the depth of early-frost damage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.39-40
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• 2022

This study is intended to examine the curing effect of the combination of the bubble sheet on the concrete by analyzing the temperature profile and core strength of the simulated concrete structure. The test results relvealed that the average temperature of the concrete applying photothermal sheet overlapped with the double bubble sheet at the bottom was 23.5℃, which had the highest insulation and insulation effect compared to other types of surface insulation curing sheets, and the core strength increased by up to 56%.