• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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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%

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 추계 학술발표회 논문집
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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.

• 한국응용과학기술학회지
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• 제28권1호
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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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• 제45권5호
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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%).

• 한국식품조리과학회지
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• 제17권5호
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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.

• 한국구조물진단유지관리공학회 논문집
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• 제24권5호
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• pp.86-94
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• 2020

고 흡수성 폴리머(SAP)가 콘크리트에 혼입되면 슬럼프가 급격하게 감소하여 시공성이 저하되며, 수분 흡수·방출 과정으로 내부 양생 효과를 얻을 수 있고, 콘크리트의 내부 공극을 증가시킨다. 본 연구에서는 감수제를 사용하여 시공성을 확보한 SAP 혼입 콘크리트의 압축강도 및 동결융해 저항성, 염화물 침투 저항성을 평가하여 내부 양생과 공극의 영향을 평가하였다. 또한 콘크리트의 양생 조건을 수중 양생과 봉함 양생으로 구분하여 SAP의 내부 양생 효과를 평가하였다. 실험 결과, SAP 혼입율이 증가할수록 감수제 사용량은 증가하였으며, 압축강도는 SAP 혼입율 1.5%가 가장 큰 압축강도를 나타냈다. 특히, 봉함 양생의 경우 수중 양생보다 큰 압축강도를 나타냈으며, 유효 물-시멘트 비 감소와 내부 양생 효과에 의해 압축강도가 증가한 것으로 판단된다. SAP를 1.0~1.5% 혼입하면 AE제를 혼입한 경우와 유사하게 동결융해 저항성이 개선되었으며, SAP를 1.0% 이상 사용하면 염화물 침투 저항성이 개선되었다. 최적의 SAP 혼입율은 1.5%이며, 2.0% 이상의 혼입율은 압축강도 및 동결융해 저항성에 악영향을 준다.

• 동아시아식생활학회지
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• 제9권4호
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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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• 제48권1호
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• pp.61-75
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• 2020

본 연구에서는 농업부산물인 왕겨와 제재과정에서 발생되는 톱밥에 환경 친화적인 소재인 숯을 첨가하여 왕겨와 숯의 혼합비율 및 밀도별로 보드를 제조한 후 용도개발을 위하여 물리적 성질을 조사하여 다음과 같은 결과를 얻었다. 왕겨 및 숯의 첨가율 별로 제조된 혼합보드의 수분흡수율과 두께팽윤율은 숯의 첨가율이 증가할수록 완만하게 감소하는 경향을 나타내었고, 또한 혼합보드의 밀도가 증가할수록 수분흡수율은 감소하고 두께팽윤율은 증가하는 경향을 나타냈다. 혼합보드의 박리강도는 밀도가 0.7g/㎤일 때 0.49N/㎟로 가장 높은 수치를 나타내었다. KSF 3104 파티클 보드의 품질기준을 만족시켰다. 왕겨 및 숯의 첨가율별로 제조된 혼합보드의 박리강도는 왕겨의 첨가율이 감소하고 숯의 첨가율이 증가할수록 박리강도가 완만하게 감소하는 경향을 나타냈다. 또한 KSF 3104 파티클 보드의 품질기준 왕겨와 숯의 비율이 35:5와 30:10일 때는 15.0형, 25:15와 20:20일 때 13.0형의 품질기준을 만족시켰다. 혼합보드의 밀도가 증가할수록 경도가 증가하는 경향을 나타냈고, 왕겨의 첨가율이 감소하고 숯의 첨가율이 증가할수록 경도는 감소하는 경향을 나타냈다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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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.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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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.