• Journal of Environmental Science International
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• v.19 no.1
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• pp.105-114
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• 2010

The objective of the paper is to experimentally investigate the compressive strength of the concrete incorporating fly ash. Ordinary Portland cement(OPC). Water to binder ratio(W/B) ranging from 30% to 60% and curing temperature ranging from $-10^{\circ}{\sim}65^{\circ}C$ were also adopted for experimental parameters. Fly ash was replaced by 30% of cement contents. According to the results, strength development of concrete contained with fly ash is lower than that of plain concrete in low temperature at early age and maturity. In high curing temperature, the concrete with fly ash has higher strength development than that of low temperature regardless of the elapse of age and maturity. Fly ash can have much effect on the strength development of concrete at the condition of mass concrete, hot weather concreting and the concrete products for the steam curing.

• Journal of the Korean Ceramic Society
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• v.48 no.6
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• pp.610-616
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• 2011

The effect of curing temperature on basic geopolymeric reactivity and hardening behaviour of blast furnace slag were investigated using the mixture of pulverized slag and several alkaline solutions of relatively high concentration. For the pastes prepared at several different temperatures between 20$^{\circ}C$ and 90$^{\circ}C$, setting time and heat of reaction were examined while mineralogical and morphological examinations were performed for the hardened paste after curing period at same temperature. The geopolymeric reaction of slag was revealed to be accelerated strongly according to the curing temperature regardless of the sort and concentration of the alkaline solution. The increase of concentration of the alkaline solution within 9M and the existence of silicic ion in the solution also promoted the reaction severely. The mineral component and their ratio of the hardened paste were revealed to be influenced by the chemical species and silicic ion contained in alkaline solution rather than by the curing temperature. The higher temperature and longer period of curing stage were effective for the sustained formation of geopolymer and succeed improvement of density and uniformity of morphology of the final hardened body.

• Restorative Dentistry and Endodontics
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• v.26 no.5
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• pp.387-392
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• 2001

When cavity floor is near the pulp, polymerization of light-activated restorations results in temperature increase. This temperature increase cause by both the exothermic reaction process and the energy absorbed during irradiation. Therefore instating base is required. Most frequently used insulating base is glass ionmer. The purpose of this study was to evaluate intrapulpal temperature changes of glass ionomer according to various curing intensity and curing time. Caries and restoration-free mandibular molars extracted within three months were prepared Class I cavity of 3$\times$6mm with high speed handpiece. 1mm depth of dentin was evaluated with micrometer in mesial and distal pulp horns. Pulp chambers were filled with 37.0$\pm$0.1$^{\circ}C$ water to CEJ. Chromium-alumina thermocouple was placed in pulp horn for evaluating of temperature changes. glass ionomer material was placed in 2mm. total curing time was 40s: continuous 40s, intermittent 20s, intermittent 10s. Glass ionomer material was cured with 300mW/$\textrm{cm}^2$, 550mW/$\textrm{cm}^2$ light curing unit. The results were as follows : 1. Temperature in pulp increased as curing unit power is increased. 2. Temperature in pulp more increased continuous emission than intermittent emission.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.103-104
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• 2019

The aim of the research is assessing the possibility of recovering the compressive strength of the mortar mixture replaced excessively high volume of blast furnace slag accidently. As a result of the experiment, in the case of compressive strength, painting sodium oxide showed higher compressive strength recovery effect than painting calcium oxide. As a curing temperature, 20℃ showed advanced result rather than 65℃. From the wet curing, the reaction was confirmed, deeper penetration depth was checked at 20℃ than 60℃ temperature. Therefore for the concrete mixture with excessively high volume of blast furnace slag, it is considered that painting sodium hydroxide and curing 20℃ can recover the compressive strength effectively.

• 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 the Korean Geotechnical Society
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• v.19 no.2
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• pp.7-14
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• 2003

A series of laboratory tests, which can show how different curing conditions influence an aging effect on clay, were carried out for the clay samples collected in the area of Kwangyang Bay and Mokpo. Clay samples were remolded and reconsolidated under three different curing temperatures (20, 50, and 80 degree Celsius) and low different curing durations (1, 7, 14, and 40 days). To find out an aging effect and geotechnical characteristics between undisturbed samples and reconsolidated samples, laboratory tests, consisting of uniaxial compression tests, CU triaxial test, and consolidation tests, were preformed. Results showed that the compression index ratio is very useful factor to indicate the aging effect of natural clays. Also geotechnical characteristics of clays reconsolidated at high temperature were very similar to those of undisturbed clays. Finally, curing temperature and curing duration influenced an aging effect on clays. The best curing condition was 80 degree Celsius and 27 days.

• Journal of the Korea institute for structural maintenance and inspection
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• v.14 no.5
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• pp.63-71
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• 2010

This paper is about a research of steam curing which is one of the curing methods for accelerating the early-age strength of pre-cast concrete. With cylinder mold and mock-up specimen, the research was executed to study the best cycle of steam curing temperature through quantifying cycle of steam curing and maximum temperature, while the required strength is developed under the early-age. Moreover, causes and measurements for the high temperature of concrete, which is due to the steam curing, and the crack, which occurs when removing steel form, are stated. Ultimately, the economical method of producing, which satisfies early-age strength development and quality assurance while manufacturing PC structure, is stated.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.4
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• pp.127-133
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• 2012

In this paper, tests were carried out to monitor the effect of the curing temperature on autogenous shrinkage of the high strength cement mortar incorporating silica fume, blast furnace slag and fly ash ranged from 10%~30% by mass of cement. The curing temperatures were varied from $5^{\circ}C$ to $35^{\circ}C$, respectively. According to results, the setting time exhibited to delay with increase of admixture and drop of temperature. As for the effect of curing temperature on autogenous shrinkage, the increase of SF and BS resulted in an increase of autogenous shrinkage, while the use of FA decrease. The higher the curing temperature is, the greater the autogenous shrinkage is. This is due to the accelerated hydration rate of cement. It is found that the maturity does not consider the effect of curing temperature on autogenous shrinkage.

• Journal of the Korean Society of Safety
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• v.12 no.1
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• pp.71-76
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• 1997

In this paper, it was described results of study on curing safety of molding meterial, about the variation of phenol resin contents, wood flour contents and moisture of wood flour, under the same condition. The experimental results are summarized as follows ; 1) When the curing temperature was high, the curing time was short in the case of 4～8wt% moisture of wood flour, but in the case of more than l2wt% moisture of wood flour, the curing time was long. 2) The curing time for curing temperature was more short when 6wt% moisture of wood flour than 4wt% moisture of wood flour. 3) The more wood flour content and moisture of wood flour content, the longer curing time and the more mineral filler content, the shorter curing time. 4) When the phenol resin content of main matrix increase, the curing time was short.

• Magazine of the Korean Society of Agricultural Engineers
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• v.26 no.3
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• pp.46-58
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• 1984

This study was carried out to investigate the compressive strength and the other effects varying to seasons and curing days on the wet curing conditions of the plain concrete. The results obtained are summarized as follows; 1. The longer the wet curing days and the higher the temperature, the greater the compressive strength was expected. 2.。$_2$8, compressive strength of concrete at 28 days under the dry curing conditions showed a range in 64-76% of that under the wet curing conditions. 3. The seasonal variations in the compressive strength under the wet curing showed in order of summer>spring=autumn>winter, and that under the dry curing were in order of spring ≒autumn> summer> winter. 4. In order to obtain 90% of the design compressive strength, 7 days in spring or autumn and 2 weeks of the wet curing in summer were required. 5. The compressive strength of concrete under the wet curing by using wet straw bag cover was almost the same as that of water curing method. 6. Under the wet curing conditions, the higher the temperature, the greater the effect of the curing of concrete was obtained, however, the compressive strength of concrete was decreased under relatively higher (over 15$^{\circ}$ C) and lower temperature (below 4$^{\circ}$C). 7. Freezing damage was occured when temperature was below 0$^{\circ}$ C and humidity was relatively high. 8. A considerable differnce between estimation of $^{\circ}$$_2$8 from $^{\circ}$7 and measured one was appeared in case of the dry curing conditions. Oregon formula was appeared to be acceptable under the wet curing conditions. 9. In relationship between $^{\circ}$$_2$8 and $^{\circ}$7~, $^{\circ}$28=1. 52 $^{\circ}$7 under the wet curing conditions except winter season, and $^{\circ}$$_2$8 =(1.39-1, 48)$^{\circ}$7 under the dry curing conditions were shown.