• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.21-26
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• 2002

This paper is intended to verify the efficiency of anti-freeze agent and insulating form by analyzing the temperature history and the property of strength-increase about the concrete that is placed in the insulating form and normal form, using new type anti-freeze agent in batcher plant According to the results about the temperature history, while the lowest temperature shows 3$^{\circ}C$ in case of normal concrete + euroform, 4$^{\circ}C$ in case of normal concrete + insulating form, it shows 6$^{\circ}C$ in anti-freeze agent + the insulating form, so the effect is most favorable. The compressive strength with mixing anti-freeze agent or not, shows high in order of standard curing, structure-managing and open air-placed specimen and the concrete mixing anti-freeze agent shows the highest compressive strength-increase.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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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.

• 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.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.392-399
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• 2003

This paper discusses the validities of insulating curing of cold weather concreting at early stage by applying insulation forms. Tests were carried out using modified insulating form combining existing insulating form and various other insulations in order to develop improved insulation form. Temperature history of concrete using various insulating forms and insulation was measured to determine most effective combination of insulting form. According to results, as for the wall form, under the curing temperature of $-10^{\circ}C$, the temperature of concrete using Euro form drops sharply before 24 hours and lasts below $0^{\circ}C$ for 7 hours. The temperature of concrete using the form combining Polypropylene panel, styrofoam and plywood panel keep above $0^{\circ}C$. And, it is confirmed that the form mentioned above has a favorable effects on enhancing strength development of concrete and the cost to make the forms shows more reasonable than that of existing forms. However, as for the combination methods of insulation form for slab, which is composed of insulating form at the bottom of slab and various surface curing materials at the top of slab, in case of exposed condition at the top of slab, temperature history of concrete goes below $0^{\circ}C$ after 10 hours. In case of the combination of vinyl sheet and curing blanket, it drops below $0^{\circ}C$ after 42 hours. However, in case of the combination of vinyl, styrofoam and curing blanket, it does not go below $0^{\circ}C$ until 55 hours. Accordingly, compared to the case of exposure and the combination of vinyl and curing blanket, it indicates that the combination mentioned above has more effective insulating performance.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05a
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• pp.11-12
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• 2011

This study examine Effect of Change of Compressive Strength of Concrete Members with Insulating Gang form on Temperature History of Concrete Positions. Test show, insulating gang forms differences and gang forms have 10℃ on peak point temperature of surface and Center if temperature history have 24Mpa by change of compressive strength. In addition, there have 14℃(16℃) on peak point temperature of surface and Center if temperature history have 40(60)Mpa. Therefore, insulating gang forms have an effect insulating performance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.4
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• pp.580-584
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• 2012

The insulating oils perform a cooling and insulation action in electric power transformer. The mineral oil has immanent fire dangerousness and environmental contamination problem. Vegetable insulating oil has higher ignition point, flash point and more excellent biodegradability than conventional mineral oil. In a real oil-filled transformers, some of the power is dissipated in the form of heat. And transformer require the heat to be removed from the winding and insulator by forced convection of the insulating oil. The flow electrification occurs when insulating oil was forced to be circulated. In this paper, influence of temperature, velocity of flow, and insulating pipe and diameter on streaming electrification of vegetable insulating oil was investigated using forced circulation apparatus. Temperature effects were most significant, and it showed a peak in the temperature $30^{\circ}C$ to $35^{\circ}C$ at insulating and copper pipe. The change of flow electrification according to area variety could be checked by change of diameter.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.617-622
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• 2001

This paper presents the effectiveness of cold weather concreting by applying both anti-freeze agent and insulating forms developed through previous study investigating insulating effects on the concrete and the strength gain. According to test results, in $-10^{\circ}C$ of air temperature, when euroforms are applied, the temperature of plain concrete drops below $0^{\circ}C$ and maintains its temperature during early 24 hours. However, when insulating forms are applied, the temperature of concrete keeps 8~$13^{\circ}C$ during first 24 hours. Insulating forms has better performance on insulating effects than existing euroforms. Concrete containing anti-freeze agent shows temperature rising effects about $1^{\circ}C$ compared to plain concrete. Strength gain of core concrete shows higher when insulating forms is applied.

• Fire Science and Engineering
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• v.22 no.5
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• pp.67-71
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• 2008

This experimental study showed the tracking characteristics of contaminated insulating materials of RCD. Electrolytes is made by IEC(International Electrotechnical Commission) 60589, NaCl added to deionized water as each 0.1 wt%. The used test equipment is application to KS(Korean Industrial Standard) C IEC 60112. The used samples is RCD(Residual Current Device) of tree companies. It is investigated carbonic electric conductive pass growth time and tracking growth form that contaminated insulators materials of RCD. As a result, carbonic electric conductive pass growth time and tracking growth form was different each companies. Track growth time of contaminated insulating materials was faster than non-contaminated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.57-58
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• 2015

In this study, the experimental study on Thermal Performance of Insulated Forms with Different Insulating Methods at Low Temperature. For this study, placing insulated plywood based form between two constant temperature chamber that maintaining 10℃, decrease temperature of one chamber to -10℃ and -20℃. Each of steps, maintaining period of temperature was 1 hour. After placing the form, measure temperature of opposite side of the insulated form. As a result of experiment, temperature difference of rigid urethane was lowest.

• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.2
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• pp.118-124
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• 2016

The purpose of this study is to analyze the rheology characteristics of insulating concrete for each type of insulation performance improvement material and utilize the result as preliminary data for optimal flow designing and pumping analysis. As a result, when lightweight aggregate was mixed, the yield stress decreased significantly, and in case of type 2, the combination of micro form cell admixture (MFA) and calcined diatomite powder (DM) showed the most ideal flow characteristics. In case of type 3, the combination of micro form cell admixture (MFA), calcined diatomite powder (DM) and lightweight aggregate (L) showed the best flow characteristics.