• Journal of Technologic Dentistry
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• v.12 no.1
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• pp.103-106
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• 1990

The purpose of this study was to determine if homogeneity of the resin associated with benchcuring could be obtained in the curing unit as the water increased from room temperature to curing temperature. The results of the experiment were as follows : 1. Long periods of bench-curing are not necessary. 2. Bench-curing can take place in the water bath of the curing unit. When this procedure is used, the water should be far enough below the temerature at which active polymerization of the resin proceeds to allow the bench-curing to occur.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.332-333
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• 2013

This research utilizes the modified sulfur having the low melting point which 65℃ is tries to study the strength property of the mortar according to the cure method of the modified sulfur mortar. And we try to use as basic data for investigating the curing condition of the light panel optimum utilizing the modified sulfur. We experimented by five kinds; 20℃ water curing method and 20, 40, 60, 80(℃) air dry curing method. In 3 day curing, the compressive strength was improved caused by high curing temperature. But the compressive strength was degraded caused by enhanced temperature in 7day curing and 28day curing. Therefore, the curing temperature of the modified sulfur mortar is determined that it comes 20 time case curing and the water curing is the most recommendable.

• Journal of Korean Society for Quality Management
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• v.16 no.1
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• pp.43-48
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• 1988

Most of silicone used for water repellent finish is MHP (methyl hydrodiene polysiloxane), which is formed by hydrolysis and condensation polymerization of MHD (methyl hydrodiene dichlorosilane: Me H Si $Cl_2$). The cross-linking theory explains the water repellent mechanism of MHP. The silicone finish on fiber could improve in handle, softness, abrasion resistance, soil repellency, tear strength and crease resistance, as well as water repellency. According to using method silicone-water repellent finishing agents, could be devided into air dry type and curing type. MHP is the typical curing type of water repellent finishing agent, and this type requires the curing temperature above $150^{\circ}C$ at least. High curing temperature is the very drawback of this curing type. For this reason, there has been global interest in the lowering of its temperature. The objective of this study is to investigate merits of alkali treatment for silicone finishing by ANOVA and LSD (least significant difference).

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.925-928
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• 2000

In this paper, physical properties of cement mortar for floor using expansion agent are discussed varied with mixing time and curing temperature, delivery time and content of added water for preventing fluidity loss. According to experimental results, slump loss shows high with elapse of time And as curing temperature goes up, it also show high when curing temperature goes up and time lag between mixing and casting increases. As curing temperature goes down, drying shrinkage shows to be decreased. But it shows decline tendency with increase of added water content.

• Advances in concrete construction
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• v.5 no.5
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• pp.481-492
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• 2017

The aim of this paper is to investigate the effect of quartz powder (Qp), quartz sand (Qs), and different water curing temperature on mechanical properties including 7, 14, 28-day compressive strength and 28-day splitting tensile strength of Ultra High Performance Concrete and also finding the correlation between these variables on mechanical properties of UHPC. The response surface methodology was monitored to show the influences of variables and their interactions on mechanical properties of UHPC, then, mathematical models in terms of coded variables were established by ANOVA. The offered models are valid for the variables between: quartz powder 0 to 20% of cement substitution by cement weight, quartz sand 0 to 50% of aggregate substitution by crushed limestone weight, and water curing temperature 25 to $95^{\circ}C$.

• Computers and Concrete
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• v.6 no.6
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• pp.437-450
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• 2009

The effect of six different curing conditions on compressive strength and ultrasonic pulse velocity (UPV) of volcanic pumice concrete (VPC) and normal concrete (NC) has been studied. The curing conditions include water, air, low temperature ($4^{\circ}C$) and different elevated temperatures of up to $110^{\circ}C$. The curing age varies from 3 days to 91 days. The development in the pulse velocity and the compressive strength is found to be higher in full water curing than the other curing conditions. The reduction of pulse velocity and compressive strength is more in high temperature curing conditions and also more in VPC compared to NC. Curing conditions affect the relationship between pulse velocity and compressive strength of both VPC and NC.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.181-186
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• 1999

When the expansive additives are used in concrete to reduce the shrinkage cracking, it shows variable properties with the curing method and curing temperature. Therefore, in this study, the experiments are perfomed to present the expansion of cement mortar by varying the unit additions of expansive additives and the curing method. According to the test results, the order of expansion by curing method, which is caused by hydration heat of cement, is follows ; curing at water > curing at air after curing at water for 7 days > curing at air. Cement mortar using expansive additives shows that high expansion is place with rise of temperature.

• 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.

• Magazine of the Korean Society of Agricultural Engineers
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• v.19 no.1
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• pp.4312-4322
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• 1977

In order to investigate the effect of the water content and the accelerated curing on the strength of the soil-cement mixtures, laboratory test of soil cement mixtures was performed at five levels of water content, four levels of accelerated curing temperatures, three levels of normal curing periods, and six levels of accelerated curing time. Also this study was carried out to investigate the effect of grain size distribution of 21 types of soils on the strength of soil-cement mixtures at four levels of cement content and three levels of curing time. The results are summarized as follows: 1. Optimum moisture content increased with increase of the cement content, but maximum dry density was changed ununiformly with cement content. Water content corresponding to the maximum strength was a little higher than the optimum moisture content along the increase of cement content. 2. In molding the specimens with the optimum moisture content, the maximum strength appeared at the wet side of the optimum moisture content. 3. According to increase of curing temperature as 30, 40, 50, and 60$^{\circ}C$, unconiiend compressive strength of soil-cement mixtures increased, the rate of increase at the early curing period was large, and approximately 120 hours was suifficient to harden soil-cement mixtures completely. 4. The strength of soil-cement mixtures at the curing temperature of 10$^{\circ}C$ decreased at the rate of 30 to 50 percent than at the curing temperature of 20$^{\circ}C$, and the strength of soil-cement mixtures at the curing temperature of 0$^{\circ}C$ increased a little with increase of curing time. 5. Although the strength of soil-cement mixtures seemed to be a little affected by the temperature difference between day time and night, it was recommended that reasonable working period was the duration from July to August of which average maximum temperature of Korea was approximately 30$^{\circ}C$. 6. Accelerated curing time corresponding to the normal curing time of 28-day was shorten with increase of curing temperature, also it was a little affected by the cement. Accelerated curing time that the strength of soil-cement mixtures for the cement of 9 percent and the curing temperature of 60was shorten with increase of curing temperature, also it was a little affected by the cement. Accelerated curing time that the strength of soil-cement mix- tures for the cement of 9 percent and the curing temperature of 60$^{\circ}C$ was 45 hours at the KY sample, 50 hours at the MH, 40 hours at the SS, and 34 hours at the JJ respectively. 7. Accelerated curing time was depended upon the grain size distribution of soil, it decreased with increase the percent passing of No. 200 sieve. 8. Relationship between the normal curing times and the accelerated curing times showed that there was a linear relationship between them, its slope decreased with increase of curing temperature. 9. The most reasonable soil of the soil-cement mixtures was the sandy loam which was a well graded soil. Assuming the base of road requiring 7-day strength of 21 kg/$\textrm{cm}^2$ being used, the soil-cement mixtures could be obtained with adding 6 percent of cement in such a sails S-7, S-8, S-9, S-10, S-11, S-12, S-13. 10. The regression equation between the 28-day and the 7-day strength was obtained as follow; q28=1.12q7,+6.5(r=0.96).

• 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.