• 한국방재학회:학술대회논문집
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• 2010.02a
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• pp.42-42
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• 2010

In order to assure the quality of concrete structure in construction process, the odor strength measured by using odor sensor was used to evaluate curing effect. Then, the compressive strength and odor strength in ordinary concrete N were shown in water curing(=standard curing), indoor and outdoor atmospheric curing condition. The difference between odor strength in the standard curing and that in each curing condition was defined as the difference in the odor strength. And the difference in odor strength in slag powder concrete BP cured in water curing(=standard curing) for different period before exposing in outdoor atmosphere in winter season were evaluated at the age of 14 days. A necessity to prolong the moisture curing for the slag powder concrete BP compared with the ordinary concrete N to obtain a required curing effect was shown by measuring the odor strength and long term compressive strength.

• Magazine of the Korea Concrete Institute
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• v.8 no.4
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• pp.141-148
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• 1996

The pulished works on Accelerated Curing Effect were generally performed around from 1960 to 1970th century for 18 to 24 hours - total curing periods. It is not possible to define the effect of temperature rise because those results were obtaine mainly by using the manually operated steam-curing tank. Thus, it may not be available to apply those data immediately on the domestic PC wall production line. The testing specimens were made from the standard mix proportion according to those of domestic PC factories to establish a basic data for the Accelerated Curing Effect. The experimental tests were conducted according to the conditions of each sub-curing periods. By comparing the results of compression tests on de-molded and 28-day water-curing specimens, we find that the most effective curing condition to obtain more than the required design strength after 28 day of water curing may be as follows: the presteaming period does not affect seriously and less than$30^{circ}C/hr$- the rate of temperature rise andless than $82^{circ}C$ - maximum temperature are necessary. It seems that post-curing procedure is very important factor to increase the effect of accelerated curing.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.107-111
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• 1996

The testing specimens were made from the standard mix proportion according to those of domestic PC factories to establish a basic data for the Accelerated Curing Effect. The experimental tests were conducted according to the conditions of each sub-curing periods. By comparing the results of compression tests on de-molded and 28-day water-curing specimens, we find that the most effective curing condition to obtain more than the required design strength after 28 days of water curing may be as follwings; the presteaming period does not affect seriously and less than $30^{\circ}C$/hr-the rate of temperature rise and less than $82^{\circ}C$ - maximum temperature are necessary. It seems that post-curing procedure is very important factor to increase the effect of accelerated curing.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.618-621
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• 2006

This paper is to investigate temperature history of cold weather concrete depending on insulation curing sheet kinds. Insulating effect according to curing sheet is shown in order of 5 layer bubble sheet, combination of PE form and 3 layer bubble sheet and 3 layer bubble sheet. It maintained above $10^{\circ}C$ of minimum temperature until the completion of initial curing period when bubble curing sheet was supplied regardless of curing sheet kinds. Five layer bubble curing sheet secure higher curing temperature than any other curing sheet applied in this experiment by as much as $2{\sim}3^{\circ}C$, which performed remarkable insulation effect. Concrete applied with curing sheet secured above $65^{\circ}D{\cdot}D$ of maturity, at which concrete had 5MPa of compressive strength at 3 days.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.170-176
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• 1997

The published works on steam curing effect have been generally concentrated on the subject, "compressive strength". However a practical test for durable steam curing concrete products has not been performed in domestic. In this study, the maximum temperature of steam is considered as a major variable to investigate the freezing and thawing resistance of the steam curing concrete. All of the specimen were cured for 24 hours which included presteaming 4 hour. Finally we found that the most effective curing condition is the case of one-day and 14-day specimens after the 24 hours steam curing at $74^{\cire}C$ degree curing temperature. It is also found that the durability of one-day samples are much weaker than those of 14-day samples. Consequently, we can conclude that the samples that produced immediately after a steam curing are more possible to deteriorate from the freezing and thawing environment.vironment.

• Magazine of the Korean Society of Agricultural Engineers
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• v.33 no.2
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• pp.61-72
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• 1991

This study was carried out to research the strength drop of concrete in dry environment. The mixing ratio of cement-fine aggregate was 1: 1, 1 : 2, 1: 3 and 1 : 4. The curing was compared standard curing with dry curing immediately after casting. It is analysis of strength change by water-proof mixing. The curing age of cement mortar was 3days, 7days, l4days and 28days. The result obtained from this study are summarized as follows. 1. The compressive and bending strength change by increasing the curing age, dry curing mortar the increasing rate of strength was decreased than standard curing mortar. 2. The compressive and bending strength change in early curing, strength difference between standard curing mortar and dry curing motar was gradually closed by increasing the W/C. 3. The dry curing mortar was decreased than standard curing mortar in decreasing rate of compressive and bending strength by increasing the W/C. 4. The compressive strength of water-proof mortar in early curing, liquid water-proof mortar was shown high strength in dry curing than standard curing. The powder and liquid water-proof mortar have a small effect in dry environment. The liquid water-proof mortar was high strength without relation change of curing age in dry environment than standard curing. 5. The compressive strength of liquid water-proof mortar in poverty mix, dry curing was shown high strength than standard curing. 6. The bending strength was increased than compressive strength by decreasing the volume of cement in early curing. The increasing rate of bending strength was decreased to compressive stength by increasing the curing age.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.825-828
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• 2006

In this paper, experimental studies are performed to find out properties of crack according to the change of curing conditions of flyash concrete. To study the effect of curing conditions on flyash concrete, slump, bleeding, air content and hydration temperature of fresh concrete are measured according to various curing conditions. In addition, the effect of caring conditions on compressive strength, tensile strength and Plastic drying shrinkage cracking of hardened concrete is also considered.

• Journal of the Korean Society of Tobacco Science
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• v.22 no.1
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• pp.13-18
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• 2000

All steps of the curing process are automatically controlled by preseted program according to stalk positions in flue-cured tobacco. The bulk curing experiment was carried out to evaluate the effect of the basic and modified curing program in curing time schedule of two bulk models in physical properties of cured leaves in a new flue-cured tobacco variety KF 114(Wicotiano tabacum L.). The curing process of KF 114 was prolonged in yellowing and quicker in browning stage than those of NC 82. There was no significant difference in physical properties and chromatic characteristics of the cured leaves between basic and modified program at two bulk models. The ratio of normal leaf color tended to increase and the greenish leaf decreased in the modified curing program of two models, but no difference in the brownish leaf ratio was olserved between two programs.

• Journal of the Korean Society of Tobacco Science
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• v.23 no.1
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• pp.12-18
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• 2001

This study was conducted to investigate the effect of tobacco curing on far infrared light on the quality of flue-cured tobacco leaves. Physicochemical characteristics such as alkaloid, total sugar, total nitrogen, starch, total phenolic compounds, browning degrees, and color differences, in cured tobacco leaves were compared between hot air and far infrared curing methods. There was no significant difference in sugar/nicotine ratio and nitrogen number between the curing methods, while the contents of ether extract and filling capacity were increase by far infrared curing. Therefore, it was expected that far infrared curing might be effective for high aroma and physical properties of the cured tobacco leaves.

• Advances in concrete construction
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• v.11 no.5
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• pp.367-374
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• 2021

The present study investigated the effect of the combined carbonation and steam curing on the physicochemical properties and CO₂ uptake of the Portland cement concrete. Four different curing regimes were adopted during the initial 10 h of curing to evaluate the potential of carbonation curing as an alternative to conventional steam curing in the precast concrete industry from environmental and practical viewpoints. Four combinations of carbonation and steam curing conditions were applied as curing regimes to the samples at an early age. The test results indicated that the samples treated with the combined carbonation and steam curing exhibited higher early strength development compared to the other samples, signifying that carbonation curing can reduce the production time of precast concrete. Furthermore, the CO₂ uptake capacity of the samples was calculated and found to be as high as 18% with respect to the mass of the paste samples. Hence, the simultaneous utilization of steam and CO₂ for the fabrication of precast concrete members has the potential to make precast concrete greener and more cost-effective.