• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.8-13
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• 1995

High flowing concrete has been made using a combination of different cementitious material. The use of supplementary cementitious material like ground granulated slag is not only interesting from an economical point of view but also from a mechanical and rheological point of view. In the case of high strength concrete, relation between the maturity and compressive strength development of high strength concrete is aproximated by appling gompertz curve and suggested new estimating method. It is the aim of this study to analysis the effect of different types of mineral fine power on the setting and compressive strength development of high flowing concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.1-4
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• 1993

This is the study on the feature of mixing method of high strength flowing concrete using the superplasticizing agent which is used to aim considerable reduction effect of water contents in the same level of consistency and workability. It is the aim of this study to compare workability and engineering properties of high strength flowing concrete according to mixing order of materials and the addition time and method of superplssticizing agent.

• Proceedings of the KAIS Fall Conference
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• 2010.05a
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• pp.135-137
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• 2010

In this paper, PLC program for flowing type steam boiler control is presented. The function of the implementation are flowing type steam boiler, PLC control, interpretation of PLC command, and temperature scheme. The flowing type steam boiler approach is based on master-slave control concept. To show validity of the developed PLC program, severial experiments are illustrated.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.3
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• pp.243-251
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• 2007

This experiment was conducted to investigate the effect of particles on the heat transfer characteristics of fluids flowing in a cold water tube. Plastic beads with 3 different sizes were used as flowing particles with cold water. An experimental test section was composed of concentric double tubes having diameters of 25mm for the inner tube and 50mm for the outer tube. The materials for the inner and outer tubes are copper and PVC respectively. It was found that the particles enhanced the heat transfer coefficient by random and vortex motion in the fluid. Hence the heat transfer coefficients for the fluid with 2mm, 5mm and $2{\times}6mm$ particles were $7%{\sim}37%$ higher than the fluid without the particles.

• Proceedings of the KIEE Conference
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• 1991.07a
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• pp.296-299
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• 1991

This paper reports the characteristics of sparkover discharge in flowing gas ranging from 0[m/s] to 30[m/s] under the needle-rod gap. The important results obtained from this paper are as followers. 1. The maximum sparkover voltage of flowing gas are about 3.1[kv](d=1[cm], 5.4[kv](d=2[cm]), 8.1[kv](d=3[cm]) higher than those of static gas 2. The empirical equation obtained from this experiment is [%]$\frac{Vs}{Re}=A\;log_{10}\;Re+B$ where A=$-7.79{\times}10$ B=$5.60{\times}10^2$ 3. The duration time of sparkover decreases with increasing the Reynolds number. 4. The discharge pattern can be controlled by adjustment of the Reynolds number

• Proceedings of the Korea Concrete Institute Conference
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• 1989.10a
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• pp.35-38
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• 1989

The purpose of this report is to investigate and analyze development and achievement of flowing and high-strength concrete by reacy mixed concrete companies in Korea. For this purpose, the investigation was divided into three parts, i.e., superplasticizers, flowing concrete, high-strength concrete. And, they were asked to quality control manager in ready mixed concrete companies. Many researches have been carried out. And, flowing concrete is applied to field in a few case. In order to improve practical applicability of high-strength concrete and make concrete strength higher, to begin with, profound research for concrete ingredients will be needed along with presentation of methods for obtaining workability and quality assurance.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.407-410
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• 2005

This research investigates experimentally an effect on the properties of the combined high flowing concrete by mix design factors. The purpose of this study is to determine the optimum mix proportion of the combined high flowing concrete having good flowability, viscosity, no-segregation and design strength(40.0MPa). For this purpose, trial mixings used belite cement+lime stone powder(LSP) are tested by mix design factors including water-cement ratio($47.9\~54.0\%$), fine aggregate volume ratio($41\~45\%$) and coarse aggregate volume ratio($41\~45\%$). As test results of this study, the optimum mix proportion for the combined high flowing concrete is as followings. Water-cement ratio $51.0\%$, fine aggregate volume ratio $43{\pm}1\%$ and coarse aggregate volume ratio $0.30{\pm}0.05m^3/m^3$ and replacement ratio of LSP $42.7\%$.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.3-8
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• 1998

This research is to examine the relationships between viscosity and fluidity according to binders in the super flowing concrete. And this research is described with respect to rheology concept, confined water ratio($\beta_p$) of binders in paste and mortar, also investigated experimentally the relationships between the relative flowing ratio ($\Gamma_m$) and the funneling velocity ratio($R_m$) on the mortar state according to the water binder ratio(W/B) and the dosage of the superplasticizer. From the confined water ratio tests, it is found that $\beta_p$ of the class C fly ash is higher than that of the class F fly and limestone in paste and mortar, therefore class F fly ash and limestone and super flowing concrete. The result of test, the optimum mix condition to the compactibility if satisfied when the replacement ratio is 30% and $K_p$ is 0.8 for the case of fly ash and limestone.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.57-62
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• 1998

As the waste concrete is increased by demolition according to the plan of city-reconstruction and preperation of city-environment etc, the production of waste concrete in the country is being very increased every years. Because the use of recycled aggregate is low, the cases of unlawful reclamation and disuse are increased. These occur the social and economic problems. This experimental study is to investigate the fluidity, compressive strength and durability of flowing recycled aggregate concrete using the river sand and recycled coarse aggregate according to the replacement rate of fly-ash and to present the fundamental data for the using of flowing recycled aggregate concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.10a
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• pp.29-34
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• 1993

Although bonding material content of the high strength flowing concrete is very important in engineering properties, in rich mix concrete increasing the bonding material content may not follow more good properties. This study is to investigate the influence of the bonding material content affecting on the engineering properties of high strength flowing concrete, and this paper is to analyze the properties of fresh concrete. The results reveal that concrete of less bonding material content has about the same good consistency as concrete of more bonding material content, and that the evaluation methods of workability have to change in high strength flowing concrete.