• 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.

• Journal of the Korea Concrete Institute
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• v.14 no.3
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• pp.275-282
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• 2002

High fluidity concrete needs high dosage of superplasticizer to acquire sufficient fluidity and high contents of fine powder and viscosity agents to prevent segregation. But it requires high manufacturing cost and has difficult in quality control. Therefore, in this paper, determination of optimal mixture proportion of segregation type superplasticizer for high fluidity concrete and manufacturing high fluidity concrete by applying developed segregation reducing type superplasticizer are discussed using flowing concrete method. According to test results, as dosage of superplasticizer increases, it shows that fluidity and bleeding increase, while air contents and ratio of segregation resistance decrease. It also shows that adding viscosity agent into it reduce bleeding and improve segregation resistance. Dosage of AE agent into it 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.

• Journal of the Korea Concrete Institute
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• v.11 no.4
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• pp.95-105
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• 1999

When superplasticizer is added to manufacture flowing concrete, the base concrete usually needs the adjustment to assure the sufficient fines contained to obtain flowable consistency without excessive bleeding or segregation. However, this may not only increase the cost, but also cause inconvenience in producing the base concrete. In this paper, the experiments are performed on normal base concrete to achieve a segregation-reducing flowing concrete by adding superplasticizer mixed with viscosity agents and AE admixtures. Three kinds of superplasticizer and two kinds of viscosity agent are selected. According to the results, with regard to the performance and cost of the admixtures, melamine type superplasticizer combined with the PEO viscosity agent and AE admixtures at the ratio 1:0.28:0.001 can acquire good quality and reduce the cost in producing the flowing concrete. With proper addition of combined superplasticizer, even though water to cement ratios of the base concrete are different, the segregation-reducing flowing concrete could be also achieved without reproportioning of the base concrete. However, it would be more desirable if the superplasticizer could be adjusted, before it is put into the practical use in order not to cause some other problems, such as rapid rate of slump loss and retarding of setting time.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.661-664
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• 2000

It is known that high flowing concrete performs much higher fluidity, segregation resistibility and better placeability than normal concrete. However, it is hard to apply high fluidity concrete in field because of high manufacturing cost. Therefore, we intend to investigate the validity of segregation reducing type superplasticizer which is made by combining 0.61 of viscosity agent and 0.022 of AE agent for 1 of superplasticizer. Test are conducted on high flowing concrete using fly ash by applying segregation reducing type superplasticizer. According to experimental results, As contents of fly ash increase, fluidity, segregation resistibility and placeability shows favorable results. And also compressive strength at early age shows to be retarded, while it gains high strength at later age.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10a
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• pp.297-300
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• 1998

Usually the flowing concrete manufactured upon normal-mixed base concrete would segregate due to the less of fine particle content. In the previous studies, a new type admixture(liquid segregation reducing type superplasticizer) has been developed to prevent such segregation without modification of base concrete mixture. In this study, the tests are performed in laboratory to evaluate the admixture by analyzing the properties of flowing concrete with different water to cement ratios, so that it could be used in the fields. According to the results, this kind of superplasticizer could improve the fluidity of concrete without causing segregation. However, it seems to be more desirable of the superplasticizer could be adjusted, before it is put into the practical use, not to cause some other problems such as rapid rate of slump and air loss and retarding of setting time.

• Magazine of the Korea Concrete Institute
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• v.13 no.3
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• pp.69-76
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• 2001

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.99-102
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• 2002

This paper discusses the estimation of construction cost of high fluidity concrete using segregation reducing type superplasicizer with 350kgf/cm2 of design strength and 60$\pm$5cm of slump flow in order to verify the cost down effect of high fluidity concrete compared with that of plain concrete with 350kgf/cm2 of design strength and 18cm of slump and with 210kgf/cm2 of design strength and 15cm of slump. According to research, 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, 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2001.11a
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• pp.28-33
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• 2001

This paper presents the results of mock up test on the manufacturing of high fluidity concrete by applying flowing methods with segregation reducing type superplasticizer(SRS). Three kinds of mock up structure are made such as. conventional concrete(A), high fluidity concrete(B) and high fluidity concrete incorporating 20% of fly ash(C). Physical and mechanical properties, temperature history of structure and nondestructive test are performed. Segregation reducing type superplasticizer is put into base concrete at field, and base concrete is also flowed at field. C mock up structure which requires 0.85% of SRS to flow base concrete shows most desirable performance at fresh state. The highest rising temperature shows the lowest at C structure among the tested structures. Strength variations before and after flowing also show the lowest values at C structures.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.327-328
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• 2010

In this paper, was determined optimal mixture proportion of segregation reducing type superplasticizer, and it was used to analyze the characteristics of the concrete. As a result, organic acid type and organic synthesis containing complex flow concrete with KASS 5T-401 are satisfied with the quality standards.

• 레미콘
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• no.7 s.68
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• pp.9-16
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• 2001

Execution of exposed concrete has some problems such as segregation, surface honey comb and insufficient surface flossing due to unsuitable mix proportion and unfavorable construction in our field. Therefore, in this paper, field application of exposed concrete at training center building of Chongju university in Daecheon are carried out based on the mixing data obtained from laboratory test. Base concrete are made in accordance with mixing data. Segregation reducing type superplasticizer developed are applied in order to flow the vase concrete with out segregation of materials. According to test results, air content shows to be reduced after flowing. Compressive strength of flowing concrete is higher than that of base concrete about 7%. Surface glossing is reducing as the age goes on. It is improved about 10% compared to that of vase concrete.