• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.477-480
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• 2003

This study discusses the fundamental properties of cement mortar with the kinds and adding ratio of stabilizing agent of recycled water. According to the results, fluidity and air content hardly make difference by the kinds and adding ratio of stabilizing agent. When recycled water is used, setting time is shortened slightly in comparison with plain mortar because of an increase of fine particle. And it is similar to the use of recycled water in the case of A, Band D(stabilizing agent), but shortened significantly in the case of C. Also, it does not show difference with variation of the adding ratio, but as the adding ratio increases, it approach to the value of plain mortar. When recycled water is used, compressive strength is similar to plain concrete, and it shows the larger value in order of D, C and A. As the adding ratio of stabilizing agent increases, it decreases at 3days, but increases at 7 and 28days. However, at the adding ratio of 0.5%, it decreases, instead. Length change ratio by drying shrinkage increases in the case of B in comparison with plain mortar, but is similar to plain mortar in the other stabilizing agent. As the adding ratio of stabilizing agent increases, it decreases, however, increases at the adding ratio of 0.5%

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.765-768
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• 2006

This paper investigates the properties of light weight foamed concrete with variances in adding ratio of stability agent(PS). Test showed that an increase of PS adding ratio decreased fluidity due to higher viscosity and increased unit weight of specimens. A sinking depth declined as the adding ratio of PS inclines, but all specimens including control concrete was ranging in KS; 0.5 to 10mm. Compressive strength value of specimens increased as PS adding ratio inclines. As for the tensile strength, any significant feature was not observed, compared with control concrete, but the ratios of camp. to tens. increased. Appearance density of concrete increased, and thermal conductivity was satisfied in KS, except for a specimen adding 0.07 percent of PS.

• Journal of the Korean Applied Science and Technology
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• v.28 no.1
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• pp.95-101
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• 2011

We estimated on the stability of W/O type emulsified fuel using by capacitance sensor, so it concluded the following conclusions. For the first 24 hours, prepared emulsified fuel reveals phase separation ratio of 5%, maintains stable status which verifies the stability of emulsified fuel. Adding more water increases the phase separation ratio rapidly, and adding more surfactant displays stable emulsification. Adding water causes larger size of water droplet diameter, and adding surfactant mixture causes smaller size of water droplet diameter. In conclusion, the size of W/O type emulsified fuel water droplet diameter is directly related to the volume of surfactant, and density of water droplet diameter changes thedistribution according to water contents.

• Steel and Composite Structures
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• v.45 no.5
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• pp.665-682
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• 2022

In the current study, punching behavior of Reinforced concrete (RC) isolated footings was experimentally and numerically investigated. The experimental program consisted of four half-scale RC isolated footing specimens. The test matrix was proposed to show effect of footing area, reinforcement mesh ratio, adding internal longitudinal reinforcement bars and stirrups on the punching response of RC isolated footings. Footings area varied from 1200×1200 mm2 to 1500×1500 mm2 while the mesh reinforcement ratio was in the range from 0.36 to 0.45%. On the other hand, a 3D non-linear finite element model was constructed using ABAQUS/standard program and verified against the experimental program. The numerical results agreed well with the experimental records. The validated numerical model was used to study effect of concrete compressive strength; longitudinal reinforcement bars ratio and stirrups concentration along one or two directions on the ultimate load, deflection, stiffness and failure patterns of RC isolated footings. Results concluded that adding longitudinal reinforcement bars did not significantly affect the punching response of RC isolated footings even high steel ratios were used. On the contrary, as the stirrups ratio increased, the ultimate load of RC isolated footings increased. Footing with stirrups ratio of 1.5% had ultimate load equal to 1331 kN, 19.6% higher than the bare footing. Moreover, adding stirrups along two directions with lower ratio (0.5 and 0.7%) significantly enhanced the ultimate load of RC isolated footings compared to their counterparts with higher stirrups ratio (1.0 and 1.5%).

• Korean journal of food and cookery science
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• v.17 no.5
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• pp.426-430
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• 2001

This experiment was carried out to investigate the effects of adding corn flour on the quality of rice cakes. Rice-corn cakes were prepared by adding corn flour at 25%, 50% and 75%, and the quality characteristics were measured. In the expansion ratio, springiness and cohesiveness of rice-corn cakes, the 25% group(C-25) was the highest and the 75% group(C-75) was the lowest. The higher the ratio of adding corn flour was, the lower the expansion ratio, springiness and cohesiveness were. In the hardness and chewiness of rice-corn cakes, the 75 % group(C-75) was the highest and the 25% group(C-25) was the lowest. But in the taste, texture and overall acceptance of rice-corn cakes, the 50% group(C-50) was the best.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.5
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• pp.86-94
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• 2020

When the Superabsorbent Polymer (SAP) is added into concrete, the slump decreases rapidly, deteriorating the workability, the internal curing effect can be obtained through the water absorption and discharge process, and the internal voids of the concrete are increased. In this study, the effects of internal curing and voids were evaluated by evaluating the compressive strength, freeze-thaw resistance, and chloride penetration resistance of SAP-adding concrete that secured workability using a water reducing agent. Also, the internal curing effect of SAP was evaluated by dividing the curing conditions of concrete into water curing and sealed curing. From the result, as the SAP adding ratio increased, the amount of water reducing agent increased, and as for the compressive strength, the SAP adding ratio of 1.5% showed the greatest compressive strength. In particular, in the case of sealed curing showed higher compressive strength than the water curing. It is considered that the compressive strength increased due to the reduction of the effective water-cement ratio and the internal curing effect. Adding 1.0~1.5% of SAP improved the freeze-thaw resistance similar to the case of adding the AE agent, and the addition of more than 1.0% of SAP improved the chloride penetration resistance. The optimal adding ratio of SAP is 1.5%, and the adding ratio of 2.0% or more adversely affects the compressive strength and freeze-thaw resistance.

• Journal of the East Asian Society of Dietary Life
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• v.9 no.4
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• pp.468-474
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• 1999

To make rice cake with squid ink, the squid ink dilulted in fifteen times was added to rice flour in the ratio of 0%, 2%. 4%, 6% and 8% respectively. Then, the squid inky rice cake was tested in physical function and chromaticity. Rheometer test was also included in this experiment. In physical function test, it showed that the inky rice cake with 6% and 8% ratio was the best in preference. In the chromaticity test, as the adding ratio of squid ink increases, the brightness decreased. The red and yellow brightness of 8% inky rice cake showed high. The results of rheometer test are as follows. In hardness, the inky rice cake with 2% adding ratio was high and the 6% inky rice cake was low. In cohesiveness, the 0% inky rice cake was high and the 8% inky rice cake was low. In gumminess, the 2% inky rice cake was high and the 6% inky rice cake was low. In brittleness, the 2% inky rice cake was high and the 6% inky rice cake was low. With correlation analysis, 1 could reach the following. The overall quality of inky rice cake was correlated with all test items except chewiness. The moistness was correlated with flavor, grain and chewiness. Also, the 8% inky rice cake was correlated with the inky rice cakes with the other adding ratios in all aspects of test. Futhermore, in the results of rheometer test. the hardness was correlated with the other three kinds of characteristics.

• Journal of the Korean Wood Science and Technology
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• v.48 no.1
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• pp.61-75
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• 2020

In this study, the environmentally friendly material charcoal was added to ricehusk, an agricultural by-product, and sawdust, which emerges during the sawing process, to produce board by mixing ratio and concentration levels of ricehusk and charcoal; it then investigated its physical properties for development purposes and achieved the following results. The water absorption and thickness swelling of the compounded board produced per adding ratio of ricehusk and charcoal showed a gradually decreasing tendency along with the increase in adding ratio of the charcoal, and as the density of the compounded board increased, the water absorption decreased, while the thickness swelling increased. The internal bond strength of the compounded board had indicated its highest value of 0.49N/㎟ at the density of 0.7g/㎤. This satisfied the quality standard for KSF 3104 Particleboard. The internal bond strength of the compounded board manufactured per adding ratio of ricehusk and charcoal showed a steady decrease with the decrease in the adding ratio of ricehusk, and an increase in the addingratio of the charcoal. Also, in cases when the ratio of the ricehusk and charcoal by KSF 3104 quality standard were 35:5 and 30:10, it satisfied the quality standard of 15.0-type, whereas it satisfied the 13.0-type quality standard if the ratios were 25:15 and 20:20. It showed a tendency of increasing hardness of the compounded board with the increase in density, and decreasing hardness with the increase in the adding ratio of the charcoal.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.473-476
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• 2003

This study discusses the use of anti-shrinkage agent as the method to reduce autogenous and drying shrinkage. According to results, as for the fundamental properties of high performance concrete, fluidity and strength decrease with an increase of the adding ratio of anti-shrinkage agent, but air content increases. Compared with plain concrete, autogenous and drying shrinkage are reduced by 12~52% and 4~22% respectively upto the adding rario of anti-shrinkage agent of 2.0%. When expansive additive is added by 5.0%, they are also reduced by 38~95% and 15~50% respectively. Therefore, as expansive additive of 5.0% and anti-shrinkage agent of 1.0% are added to high performance concrete of around W/B 30%, it is considered that fluidity and strength are hardly influenced, and in addition, crack by shrinkage can be prevented effectively.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.03a
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• pp.445-452
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• 2001

Generally, OPC(ordinary portland cement) is used for grouting in Korea, and bentonite has usually been added to prevent the deposition of cement particles. The dispersion of CB(cement bentonite) grout is influenced by variable factors i.e. water to cement ratio, particle size of cement, kind of bentonite, adding volume, methods of adding, viscosity of CB grout materials and curdling time. Among variable factors, the viscosity of CB grout materials is influenced by the dispersion, and dispersion is improved as increasing the mixing speed. In this paper, described a suitable mixing speed of the High Speed Mixer in field, engineering characteristics of CB grout materials vary with the water to cement ratio and the mixing speed as well as confirming the state of dispersion.