• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.75-76
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• 2019

The purpose of this study is to achieving a sufficient fluidity without segregation for normal strength grade concrete mixture. therefore in this research, by analyzing the various superplasticizer dosages on the concrete mixture, the segregation range was analyzed to provide a proper concrete mix design with sufficient fluidity.

• Journal of the Korea Institute of Building Construction
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• v.22 no.5
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• pp.441-450
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• 2022

In this study, the fluidity and strength characteristics of NSC mortar according to the type and rate of addition of superplasticizer were analyzed to secure the fluidity of NSC composed of only slag and ash. Through the flow test, it was found that the fluidity of NSC was related to the basicity according to the binder condition, and the lower the reactivity, the higher the fluidity. When polycarboxylate is added, NSC mortar is considered to be more advantageous than plain mortar in terms of securing fluidity. As a result of the strength tests of NSC mortar containing Lignin or Polycarboxylate superplasticizer, it was found that the strength tends to increase as the basicity increases. In addition, when polycarboxylate is added, it is judged that the NSC mortar can secure adequate fluidity and strength at the same time. Through this experiment, an appropriate binder condition that satisfies the flowability while securing the strength was derived.

• Korean Journal of Construction Engineering and Management
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• v.1 no.2 s.2
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• pp.63-70
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• 2000

Since inorganic pigment, among admixtures used for cement composites, can raise the esthetic value of a building due to its effect of coloring, it can be assumed that the quantity consumed is expected to increase in connection with the recent trend of emphasizing the beautiful sights of the city. We carried out a flow test by changing the mix proportion of the cement mortar mixed with an inorganic pigment, water-cement ratio and pigment mixing ratio in order to present the basic materials for utilizing colored cement mortars. In construction by exploring the effect of inorganic pigments on the workability of cement mortar. In case of red pigment mortar and yellow pigment mortar, the workability was found to be rapidly decreased. To secure proper workability, it is necessary to increase the amount of mixing water, or to use superplasticizer. In case of green pigment mortar, however, it recorded $-2.4{\~}6.9{\%}$, showing that there was almost no change in flow. In case of black pigment mortar, it was also confirmed that there is no need to consider workability.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.429-435
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• 2017

The aim of the research is, for normal strength range concrete mixture, to evaluate the fluidity development and robustness of the mixture depending on various water reducers. Although a usage of water reducer has been essential to make a concrete under the current conditions of worsen aggregate quality, selection of appropriate performance of water reducer is significant. Hence, in this research, regarding the normal strength range mortar, three different performance of water reducers were evaluated in aspects of securing fluidity, and robustness, rheological behaviors. Additionally, for the concrete mixture, the fluidity change was evaluated depending on unit water content for each different water reducer, and the water reducing performance with manufacturing cost was compared and analyzed. By the result of this research, it is expected to provide a case of determining appropriate kind of water reducer and to contribute on conditions of securing sufficient fluidity with stable quality and economical advantage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.95-96
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• 2023

In this study, the table flow of fiber reinforced cement composites mixed with CNTs dispersed differently according to the dispersion method was evaluated. The mixture was composed of plain mixture according to the presence or absence of ultrasonic dispersion and PCE-based dispersants A and B of 0.5% and 1.0%, respectively, CNT was mixed with 0.03% of cement weight and fiber was mixed with 1.5% of total volume. As a result of the experiment, NC-A0.5 showed a fluidity similar to that of P without CNT. The fluidity of NC-A0.5 and P-N showed a similar tendency, which is considered to be due to the distribution of evenly dispersed CNT particles without agglomeration between cement particles due to the dispersant. NC-B0.5 showed a similar level of firmness to P-U, but after hitting 250 mm, B Agent seems to have a significant effect on liquidity improvement.Both NC-A1.0 and NC-B1.0 seem to have increased flow due to excessive dispersion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.180-181
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• 2021

This study compared and analyzed the fluidity, compressive strength, and unit weight characteristics of mortar using bottom ash aggregates as part of a study to develop alternative aggregates

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.04a
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• pp.148-149
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• 2022

The use of high-strength grout applied for facility foundations and bridges has recently been expanding in offshore wind farm. Wind farm in offshore require bearing capacity for horizontal loads such as wind, waves, and earthquakes. In order to improve the bearing force of the base part, sufficient fluidity and a certain strength should be ensured so that the high-strength grout is densely charged in the narrow space of the connection part. Therefore, in this study, changes in fluidity and strength according to the ratio of PC-based superplasticizer mixed in high-strength grout were measured. As a result, as the ratio of the superplasticizer increased, fluidity increased and strength decreased. However, the strength did not decrease when the ratio of superplasticizer was above a 0.005. Therefore, it was confirmed that the fluidity change was remarkable when a 0.005 ratio of PC-based superplasticizer were added.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.215-216
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• 2021

In this study, the liquidity and compressive strength characteristics of concrete mixed with self-healing capsules were analyzed as part of the study to improve the problems of cracks and maintenance of concrete structures.

• Resources Recycling
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• v.27 no.6
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• pp.30-37
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• 2018

A series of experiment was conducted to evaluate basic performances of low-pH, anti-washing grouts incorporating gypsum which applied for reinforcing underwater cavities in limestone- grounds. Various types of mix proportions were designed and the fluidity, strength and environmental impact of these mixtures were evaluated. The flowability was evaluated under two conditions, i.e., flows without and with pressing, respectively. Strength was measured for the hardened mixtures fabricated under conditions of air and water injections. The environmental impacts including the pH of the suspension and the suspended solids concentration for the mixtures were evaluated. The low pH of fresh mixture suspension, below than 10, was achieved by incorporation of gypsum. The mix proportions of cement-quartz powder-gypsum binders and chemical agents resulted in mortar natural flow 7-10 cm and uniaxial compressive strength 4 MPa were derived.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.128-129
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• 2014

In this study, flowability of the mortar added with length change and combination of steel and inorganic fiber has been tested to evaluate the performance of fiber-reinforced mortar. The following results could be made as the conclusion. Early age flow of the mortar has been decreased when fibers added. Slump also decreased with the adding of fibers. For the air content, comparing with Plain, all the specimens with fibers showed higher air content than Plain., Addition of every kinds fibers showed the similar EIS test results.