• Journal of the Korea Concrete Institute
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• v.15 no.2
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• pp.217-224
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• 2003

It is necessary to reduce bleeding, which is a kind of segregation of fresh concrete, for improvement of quality of concrete structure. But, besides using high qualify material and adjusting mixture ratio, there is no easy solution to reduce bleeding by now. For that reason, this study is intended to develop bleeding reduction agent and to investigate its application. The test results are following. At first, recommended mixture ratio of bleeding reduction agent is proven to be MC viscosity agent : defoaming agent : superplasticyzer of 1 : 0.004 : 0.2. It goes to prove that bleeding reduction agent does not have bad effect on the quality of concrete such as fluidity, air content and the strength of hardened concrete etc, and can reduce bleeding effectively. Therefore it is thought that bleeding reduction agent can be applied to construction field effectively.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.68-69
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• 2019

Integrating 3D printing into architecture is gaining attention because it allows construction of construction structures without formwork. Among them, 3D printing construction materials must have high flow performance and at the same time ensure the performance that does not collapse during lamination. Therefore, in this study, we tried to determine the fluidity and lamination properties of mortar formulations, and set the thickener incorporation ratio as the formulation parameters. As a result of this experiment, it was confirmed that the lamination performance was secured from the thickening agent mixing rate of 1.5%.

• Korean Journal of Food Science and Technology
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• v.40 no.4
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• pp.474-478
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• 2008

This study was carried out to evaluate the rheology of flour doughs containing 0.5% of hydroxypropylmethyl-cellulose (HPMC), methylcellulose (MC), and sodium alginate (SA), respectively. Farinograms, alveograms, a rapid visco analyzer (RVA), and rheofermentometer were employed in the analysis. According to the farinogram tests, the hydrocolloid additions caused changes in water absorption, dough development time, stability, and breakdown. The dough containing HPMC had the highest water absorption at $67.4{\pm}0.12%$. The HPMC dough also had the longest development time ($8.2{\pm}1.04$ min), stability ($12.7{\pm}0.42$ min), and breakdown ($7.9{\pm}1.3$ min). From the alveogram tests, P, G, and PIL values increased, whereas the L value decreased. The W values of the HPMC and SA doughs were increased, but that of the MC dough was decreased. According to the RVA results, the HPMC and SA doughs had reduced initial pasting temperatures whereas that of the MC dough was increased, but the difference was not significant. The peak viscosity of the MC dough also increased. Furthermore, all the doughs had increased breakdown times and decreases in final viscosity and setback. In the rheofermentometer tests, the HPMC dough presented the highest $H_m$, and the SA dough had the largest total volume.