• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.281-286
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• 1998

The aim of this study is to compare the development of compressive strength of high-Flowing concrete with maturity and to investigate the applicability of strength prediction models of concrete. An experiment was attempted on the high-flowing concrete mixes using Ordinary portland cement, High belite cement, Blast furance slage cement and replaced Fly-ash of 30% by weight of Ordinary portland cement, the water-binder ratios of mixes being 0.35 and the curing temperatures being 30, 20, 10, 5$^{\circ}C$. Test results of mixes are statistically analyzed to infer the correlation coefficient between the maturity and the compressive strength of high-flowing concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.10a
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• pp.385-390
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• 1997

In the mixing proportion of high flowing concrete we have to use quantity of power such as cement and superplasticizer, and increase the proportion of fine aggregate more than that of plain concrete to increase flowability and segregation resistance. Therefore, the fresh state of high flowing concrete is largely affected by superplasticizer and change of grade the percentage of surface water. This study aims at development of self-filling up high flowing concrete without compaction, in case of using the fine aggregate of standard grade range, by examination on the influence of fresh state of high flowing concrete, and by understanding influence on various fluidity such as flowability, reinforcement passibility, fillingability, segregation resistance.

• 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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• 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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• 2008.04a
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• pp.461-464
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• 2008

This study is compactability and Passing ability to get to know the flowing characteristic of high flowing self-compacting concrete with mixing steel fiber of various size and diameter. After flowing test, size and diameter are getting longer, flowing performance is getting lower. It meets the standard of combined high flowing self-compacting concrete of JSCE 2 grade and passing performance from ASTM C 1621. Through this study, it can be possible to be applied in site of HSCC with mixing steel fiber.

• Journal of the Korea Institute of Building Construction
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• v.3 no.3
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• pp.121-126
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• 2003

This study investigated about several mix factors came up to drying shrinkage and carbonation of high flowing concrete using viscosity. The results are as follows; Drying shrinkage ratio of high flowing concrete using viscosity showed higher for early age, but lower than normal concrete as long age. Also, drying shrinkage ratio and reduction ratio of mass showed higher and relative dynamic modulus of elasticty showed lower as W/C was higher generally. And in case of high flowing concrete using viscosity, carbonation wasn't confirmed without the kinds of cement and viscosity except 50C.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10b
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• pp.1242-1247
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• 2000

Results from a study on the effect of the chemical agent on the flowing and setting properties of high flowing.high strength concrete using blast-furnace slag are presented in this paper. The flowing and setting properties of concrete are investigated by slump, slump-flow, flowing velocity, L-flow, velocity of V-funnel, L-spatial passability and setting time. In addition, kinds of chemical agent were composed of naphthalene type, of naphthalene and melamine and melamine type. The results indicate that dispersive capacity can be increased by naphthalene composition. Also, it shows that viscosity and early strength can be increased by melamine composition.

• 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.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.743-746
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• 2004

This research investigates experimentally an effect on the properties of the high flowing concrete according to variations of concrete materials and site conditions. Variations of sensitivity test are selected items as followings; (1)Concrete temperature, (2)Unit water(Surface moisture of fine aggregate), (3)Fineness modulus of fine aggregate, (4)Addition ratio of high-range water reducing agent. And fresh conditions of the high flowing concrete should be satisfied with required range including slump flow$(65{\pm}5cm)$, 50cm reaching time of slump flow$(4\~10sec)$, V-box flowing time$(10\~20sec)$, U-box height(min.300mm) and air content$(4{\pm}1\%)$. As results of sensitivity test, material variations and site conditions should be satisfied with the range as followings; (1)Concrete temperature is $10\~20^{\circ}C$ (below $30^{\circ}C$), (2)Surface moisture of fine aggregate is within ${\pm}0.6\%$, (3)Fineness modulus of fine aggregate is $2.6{\pm}0.2$ and (4)addition ratio of high range water reducing agent is within $1\%$ considered flow-ability, self-compaction and segregation resistance of the high flowing concrete.

• Journal of the Korea Institute of Building Construction
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• v.4 no.2
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• pp.129-136
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• 2004

High fluidity concrete(HFC) requires high dosage of superplasticizer to acquire sufficient fluidity, and high contents of fine powder and viscosity enhancing admixtures to resist segregation. The use of high amount of admixtures to make HFC at batcher plant in ready mixed concrete company is one of the reasons to raise the manufacturing cost of HFC. For this reason, new type of manufacturing method of HFC are described using both flowing concrete method and segregation reducing superplasticizer(SRS) in order to gain economical profit and offer the convenience for quality control.. As dosage of melamine based superplasticizer increases, it shows that fluidity and bleeding increase, while air contents and ratio of segregation resistance decrease. It also shows that addition of viscosity agent into superplasticizer reduce bleeding and improve segregation resistance of concrete. Dosage of AE agent into superplasticizer containing viscosity agent recovers loss of air contents during flowing procedure. Combination of proper contents of superplasticizer, viscosity agent and AE agent make possible to develope segregation reducing type superplasticizer. Compressive strength of high fluidity concrete applying flowing method with it is higher than that of base concrete. No differences of compressive strength between compacting methods are found. For the estimation of construction cost of high fluidity concreting using segregation reducing type superplasicizer, under same strength levels, although material cost of high fluidity concrete is somewhat higher than that of plain concrete due to segregation reducing type superplasticizer cost, labor cost and equipment cost of high fluidity concrete is cheaper than that of plain concrete. However, based on the strength differences, high fluidity concrete shows lower material cost, labor cost and equipment cost than that of plain concrete due to decreasing in size of member and re-bar caused by high strength development of concrete.