• Journal of the Korean Recycled Construction Resources Institute
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• v.4 no.4
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• pp.489-495
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• 2016

In this study, the Warm-Mix Asphalt was prepared using a modified Sulfur Binder mixed with an additive of a polymer component in sulfur, which is an industrial by-product generated in the crude oil refining process. The dynamic stability and durability characteristics of the prepared Warm-Mix Asphalt was evaluated by the indirect tensile strength, the tensile strength ratio before and after water immersion and freezing-thawing, and the dynamic stability by wheel tracking test. The Warm-Mix Asphalt Mixtures using Modified Sulfur Binder has a tensile strength ratio before and after water immersion of 0.88, which is about 1.13 times that of the Warm-Mix formed modified Asphalt, and the tensile strength ration before and after freezing-thawing is also 0.82, thus, all tensile strength ratios satisfied the KS quality standard value of 0.75 or more. The indirect tensile strength was 1.6MPa which was twice the KS quality standard value of 0.8MPa, and about 1.24 times higher than that of normal heated asphalt 1.29MPa. In addition, the dynamic stability by the wheel tracking test was 14,075 times/mm, which was about 15 times higher than that of normal heated asphalt and about 3 times higher than that of the Warm-Mix formed modified Asphalt, showing excellent resistance to plastic deformation such as fatigue cracks.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.549-554
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• 2002

In Powder System, SCC demands high dosage of superplasticizer and a lage amout of powder for suitable fluidity and viscosity. Okamura's method of most representative mixing design method in SCC of Powder-System is unfavorable economically because of using a large amount of powder. In addition, many ready-mixed concrete plants do not use his mix design method and procedure due to complexity for practical application. Therefore, Nan Su proposed more simple mix design method than Okamura's. It had an advantage in simplicity in practical application and required a smaller amount of powders compared with Okamura's method. This paper proposed an optimal mixture proportion of SCC with consideration of Nan Su's method. The new and modified mix design method required a smaller amount of powder than that of Nan Su's. To check the properties of SCC, considered with the requirements specified by the Japanese Society of Civil Engineering.(JSCE)

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.215-216
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• 2012

The purpose of this study is to analyze the situation and feature of construction technology by analysis properties and the mixture proportion of a reinforced concrete building from the modern domestic and to leave technological records for the optimal maintenance of the cultural heritage. The study says, the case of the 1:3:6 mix concrete has been standard regardless of the kind of structures after the concrete has being used in earnest, However, The strength range is big from Water-Cement ratio difference according to the concrete casting site.

• Magazine of the Korea Concrete Institute
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• v.4 no.4
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• pp.149-160
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• 1992

콘크리트 압축강도가 설계의 규준이 될 경우 배합비를 결정하는 방법은 여러 가지가 있으나, 파괴에너지 및 탄성계수와 같은 규준이 주어질 경우 배합비 결정에 적용하는 방법은 거의 없다. 이를 위하여 본 연구는 콘크리트 재료성질의 관계에 관한 배합설계도(Mix design diagram)를 제안하였다. 이 방법은 시멘트량, 물-시멘트 비가 콘크리트의 압축강도, 탄성계수, 할렬인장강도, 파괴에너지 그리고 콘크리트 특성길이(Characteristic length)에 주는 영향을 실험에 의하여 규명하였다. 시편제작을 위하여 각기 다른 물-시멘트비와 워커빌리티를 갖는 6종류의 무근콘크리트 배합이 사용되었다.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.97-102
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• 1997

In this study, a predictive method which was modified from KIshi's model for the temperature development of concrete was developed by using mineral compounds of clinker and pozzolans. Temperature dependent heat generation of reaction was also considered. Specific heat considering the effect of mix proportion and temperature was calculated with experimental data in the literatures. Thermal conductivity considering the effect of mix proportion and temperature was experimentally investigated. Through this research it was found that the developed method considering thermal properties accurately predicted adiabatic temperature rise of concrete without the experiment. It was also found that the thermal conductivity of concrete could be predicted by the volume ratio of each component of mix proportion and was independent of temperature within the normal climatic range.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.103-110
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• 1997

The objective of this study is to provide the information on the small-scale model mix proportion when the behavior of prototype concrete pavement is studied through small-scale model experiments. However it is difficult to obtain a model material to simulate the prototype concrete by scaling the individual components according to the laws of similitude. In this paper, the stress-strain behavior in uniaxial compression is used as a means to correlate materials similitude between the prototype and the model concrete. Based on th results of experiments, We compared the stress-strain curves of prototype and model concrete mixes using a nondimensional basis. In order to simulate the stress-strain curves of prototype concrete, it is important that various mix as of model concrete selected properly which are varied from aggregate grading, cement-aggregate and sand-aggregate ratio.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.11a
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• pp.49-52
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• 2003

The objective of this study the mechanical characteristics of prefoamed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/㎠ or more compressive strength, when was unit weight 0.8t/㎡. In the case of the same unit weight of concrete, it is influenced by w/c of foam agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufatured with the different factors in mix design and also present optimum mix proportion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2003.05a
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• pp.49.1-52
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• 2003

The objective of this study the mechanical characteristics of preformed lightweight foamed concrete using the mineral foam agent which has high lightness, and strength. The compressive strength of lightweight foamed concrete using mineral foam agent are about 2 times degree high those the of lightweight foamed concrete using vegetable foam agent. Lightweight foamed concrete was able to obtain the result of 50kg/$\textrm{m}^3$ or more compressive strength, when was unit weight 0.8t/$\textrm{m}^3$. In the can of the same unit weight of concrete, it is influenced by w/c of loan agent ratio. The paper present extensive data on characteristics of compressive strength of the concrete manufactured with the different factors in mix design and also present optimum mix proportion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05b
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• pp.67-68
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• 2010

Recently, there were not enough studies regarding the mix adjustment and changes of normal physical properties of slump flow type concrete in domestically. Therefore in this paper, it is aimed securing the fundamental data about flow its mix design method by experimental research. The experiment includes the adjustment of the way for slump flow type concrete by the variation of size of coarse aggregate. In the result, it is advisable raising the ratio of fine aggregate and unit water amount by considering the specific surface when increasing the Gmax size.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.193-194
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• 2019

The purpose of this study is to design the basic mix proportions of antiwashout underwater polymer cement mortar as a repair material. The antiwashout underwater polymer cement mortars are prepared with various mix proportions using three type polymer dispersions without or with antifoamer. From the test results, the whole antiwashout underwater polymer cement mortars can be cast underwater without segregation like plain mortar. It is apparent that the flexural strength of antiwashout underwater SBR cement mortars with antifoamer at polymer- cement ratios of 5% and 10% is higher than that of plain mortar irregardless of a little low compressive strength.