• Journal of the Korea Institute of Building Construction
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• v.18 no.3
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• pp.267-275
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• 2018

This study is to investigate the effect of various temperature and humidity conditions on the strength and efflorescence of alkali activated slag cement(AAS) using the red mud. As a result of examining the strength and efflorescence characteristics of AAS mixed with red mud according to the curing conditions, The compressive strength and flexural strength were the highest at 28 days, but the absorption rate, efflorescence area and soluble $Na^+$ elution were lowest in standard wet curing compared to the air curing, high temperature curing and low temperature curing.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.260-267
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• 2021

The purpose of this study was to experimentally investigate the effects of curing methods on the compressive strength and tensile behavior of alkali-activated slag-based fiber-reinforced composite with a water-to-binder ratio of 15%. Three kinds of mixtures according to the curing conditions were prepared and compressive strength and tension tests were performed. Test results showed that the compressive strength and the first cracking strength of composites decreased when high temperature curing and air curing were adopted, while tensile strain capacity of composites increased. It was also observed that crack spacing and crack width of composites decreased by applying high temperature and air curing.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.31-36
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• 2008

This study aims to examine the effects of thickness of the concrete members and curing temperature on the properties of low heat concrete through heat of hydration analysis. Type of the members that was analyzed in the experiment is ternary mixture of ordinary portland cement, blast-furnace slag incorporating ratio(20%) and fly ash incorporating ratio(30%), which formed a mat foundation. Thicknesses of the concrete members were 1, 2 and 3(m) and three levels of curing temperatures were 10, 20 and 30(℃). They were applied to analyze the effects on the temperature and thermal cracking index. As a result, for temperature history, temperature difference between the central area and the surface tended to decrease as the thickness of the concrete members get thinner. For the temperature cracking index, on the other hand, the risk of cracking tended to decrease as the curing temperature gets higher and as the thickness gets thinner.

• Journal of the Korean Society of Tobacco Science
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• v.20 no.1
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• pp.13-18
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• 1998

In the flue curing process, the wet bulb temperature is usually controlled at a constant level. To improve the quality of flue cured leaves, we studied the effect of the cyclic change of wet bulb temperature at the yellowing stage of flue curing on physical properties of cured leaves. The wet bulb temperature was automatically controlled between preset high (38℃) and low point (35℃) every one hour cyclically. As a result, the acceleration of the increase in the physical properties of cured leaves were observed. The leaves cured by this method were more or less orange in color, better bodied, and less brittle compared with the leaves produced by conventional curing. However, the leaves cured by this method had a little sharpness and harshness. As to the physical properties, there was decreased in occurrence of flat leaves than that of conventional ones. On the other hand, in case of cyclic curing method, increase of price per kg reached to 2-3% compared with those of conventional ones.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.19-22
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• 2003

The purpose of this study is to analyze the curing effect of planar surface heater for concreting in cold weather. Some experiments were conducted to evaluate the temperature history of concrete structures cured with heating sheets. Results are as follows ; (1) The temperature of concrete showed continuously rising trend with the heating by planar surface heater under the cold environmental condition of 3~-12$^{\circ}C$. And after about 24 hours the maximum temperature of concrete was reached at 25~3$0^{\circ}C$. (2) The temperature of slab concrete heated by planar surface heater of 130W/$m^2$ was at least $25^{\circ}C$ higher than that of an exterior air, and the curing performance was much more effective than heating by hot wind machine. (3) Through the curing by planar surface heater for 48 hours, the concrete maturity of about 1.5 times to heating by hot wind machine was acquired.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.553-556
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• 2003

This study is analyzed about the factor of adhesive strength characteristics, curing time, asphalt application, test temperature which are liquid waterproofing membrane of rubber-asphalt and chloroprene-rubber type for concrete bridge deck. According to the results, curing time is shorter, adhesive strength is less in chloroprene-rubber type. And also chloroprene-rubber and rubber-asphalt type are showed high adhesive strength in low temperature.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.143-144
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• 2019

This study introduces the production and construction of building interior and exterior materials using UHPC for premix type room temperature curing developed through advance research and development.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.163-166
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• 1999

In this paper, strength development of concrete using blast-furnace slag cement(BSC) and ordinary portland cement(OPC) are discussed under varius W/C and curing temperatures. According to the experimental results, strength development of BSC concrete is lower than that of OPC concrete in low temperature at early age and maturity. In high curing temperature, BSC concrete has higher strength development than that of low temperature regardless of the elapse of age and maturity. BSC has much effect on the strength development of concrete at the condition of mass concrete, hot weather concreting and the concrete products with the steam curing, which is influenced by high temperature.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.4
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• pp.16-21
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• 2002

It was observed that drying temperature and curing time in the paper coating process as well as Tg of the latex used as a binder, greatly affected the properties of the coated paper such as roughness, paper and print gloss, K & N ink drop, and ink set-off. The higher drying temperature induced faster water evaporation and change in binding density, which caused an increase in paper roughness, ink gloss and ink set-off, but decrease in paper gloss and K & N ink drop. The increased curing time promoted latex filming and redistribution of the binder in coating layer. This increased pick strength and ink gloss, but decreased ink trapping. Finally, the higher Tg of the latex showed the wider changing range of these properties.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.263-267
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• 1995

The usual methods for the temperature control of mass-concrete structures include the use of low-heat cement, pre-cooling, post-cooling, or sheet curing. In order to control the heat of hydration during the construction of mass-concrete structures, the combination of the above methods is commonly employed. For the construction of mass-concrete structures such as massive pier or anchor, it is necessary to control the curing temperature with pipe cooling. In this study, the method of analysis on the effect of pipe of was proposed to prevent the thermal cracking due to heat of hydration In addition the effect of covering the concrete surface with blanket insulation was investigated. The results of the present study may be useful for the prediction of curing temperature of mass-concrete structures and the reasonable construction management.