• KCI Concrete Journal
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• v.11 no.3
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• pp.19-28
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• 1999

This study treated self-compacting high Performance concrete as two Phase materials of Paste and aggregates and examined the effect of powder and aggregates on self-compacting high performance, since fluidity and segregation resistance of fresh concrete are changed mainly by paste. To improve the fluidity and self-compactibility of concrete, optimum powder ratio of self-compacting high performance concrete using fly ash and blast-furnace slag as powders were calculated. This study was also designed to provide basic materials for suitable design of mix proportion by evaluating fluidity and compactibility by various volume ratios of fine aggregates, paste, and aggregates. As a result, the more fly ash was replaced, the more confined water ratio was reduced because of higher fluidity. The smallest confined water ratio was determined when 15% blast-furnace slag was replaced. The lowest confined water ratio was acquired when 20% fly ash and 15% blast-furnace slag were replaced together. The optimum fine aggregates ratio with the best compactibility was the fine aggregate ratio with the lowest percentage of void in mixing coarse aggregate and fine aggregate In mixing the high performance concrete. Self-compacting high performance concrete with desirable compactibility required more than minimum of unit volume weight. If the unit volume weight used was less than the minimum, concrete had seriously reduced compactibility.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.23-26
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• 1999

The properties of concrete can be affected by high range water reducing agent and cement. The data for compatibility and effect of fluidity is reported already according to the mixing proportion of kinds of cements and high range water reducing agents. Moreover, the international market of construction has been opened, the international standard of capability has been promoted and the international exchange of construction materials has been brisked. This study investigated fluidity properties of mortar due to kinds of cements and high range water reducing agents which are producted in different nations. Also studied were the compatibility effect of cements and high range water reducing agents.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.345-353
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• 2014

This study was evaluated influence of fluidity properties according to basalt fiber and high volume fly ash in the mortar level, as part of a basic study for development of fiber reinforced concrete using basalt fiber and high volume fly ash. In the first step, it was evaluated that fluidity properties of mortar according to replacement ratio 6 level of fly ash(10, 20, 30, 40, 50 and 60mass%) and fluidity properties of mortar according to content 5 levels of SP(1.3, 1.5, 1.7, 1.9 and 2.1%) and content 5 levels of VA(0.2, 0.4, 0.6, 0.8 and 1.0%) for dispersion of the basalt fiber, in the second step, it was evaluated that fluidity properties of mortar using High-volume fly ash (50mass%) on 3 levels of basalt fiber length (6, 20 and 30mm). Results of assessment, if after a fiber mixed, it showed that viscosity agent is more effective to improve the fluidity and fiber dispersion than superplasticizer, high volume fly ash (50%) applying the mixing, due to three properties of fly ash, showed that the improved fiber dispersibility and flow improvement.

• 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 Korea Concrete Institute Conference
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• 2001.05a
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• pp.641-646
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• 2001

Generally, when Fly-Ash was used as replacement material of cement in concrete, it might occur retardation of setting and hardening. So, it is unable to use a large amount of Fly-Ash as replacement for cement. However, if it is used as replacement material of fine aggregate in concrete, we can use a large amount of Fly-Ash and settle a problem of natural-aggregate exhaustion. Furthermore, engineering properties of High Volume Fly-Ash Concrete Is better than that of plain concrete But, the larger Fly-Ash is replaced, the more fluidity of High Volume Fly-Ash Concrete decrease, because porous organization of Fly-Ash adsorb water and Superplasticizer. In this study, after appending additional water to High Volume Fly-Ash Concrete in proportion to weight of Fly-Ash, we intend to find proper ratio which doesn't affect strength and satisfy fluidity As a result of this study, it was found that fluidity of mortar with 25~28 percentage of additional water was satisfied with fluidity of plain mortar, and compressive strength of that was similar to plain mortar's

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.312-315
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• 2004

The effects of polymer-cement ratio, antifoamer content and shrinkage-reducing agent content on the strength of high-fluidity polymer-modified mortars using redispersible polymer powder are examined. As a result, the flexural and tensile strengths of the high-fluidity polymer-modified mortars using redispersible polymer powder tend to increase with increasing polymer-cement ratio, and tend to decrease with increasing shrinkage-reducing agent content, regardless of the antifoamer content. However, the compressive strength of the high-fluidity polymer-modified mortars using redispersible polymer powder decrease with increasing polymer-cement ratio and shrinkage-reducing agent content.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.296-299
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• 2004

The effects of polymer-cement ratio, antifoamer content and shrinkage-reducing agent content on the setting time and drying shrinkage of high-fluidity polymer-modified mortars using redispersible polymer powder are examined. As a result, the setting time of the high-fluidity polymer-modified mortars using redispersible polymer powder tend to delayed with increasing polymer-cement ratio, regardless of the antifoamer conten,. Irrespective of the antifoamer content, the drying shrinkage of the high-fluidity polymer-modified mortars using redispersible polymer powder tend to decrease with increasing polymer-cement ratio and shrinkage-reducing agent content.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.262-263
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• 2014

The purpose of this study was to investigate properties of high fluidity concrete adding waste marble powder. A change in the replacement ratios of waste marble powder was measured compressive strength and slump flow, O-Lot and U-Box. Waste marble powder has replaced binder of high fluidity concrete at certain contents of 0~20%. As a results, Slump flow, O-Lot and U-box adding waste marble powder up to 10% have increased by adding waste marble powder. As the concrete with a replacement ratio of waste marble powder up to 10% was found to have a compressive strength superior to that of plain.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.101-102
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• 2019

The use of high fluidity concrete has been added in recent construction work. In this study, we analyzed segregation resistance due to admixture substitution of the system high fluidity concrete that was hardened. The research results show that the resistance to segregation at the time of admixture replacement is improved. The best results were shown with a ternary system mixed like FA and BS.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.691-694
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• 2004

The effects of polymer-cement ratio and antifoamer content on the setting time and durability of high-fluidity polymer-modified mortars using redispersible polymer powder are examined. As a result, the setting time of the polymer-modified mortars using redispersible polymer powder tend to delayed with increasing polymer-cement ratio, regardless of the antifoamer content. The water absorption and chloride ion penetration depth of the high-fluidity polymer-modified mortars using redispersible polymer powder decrease with increasing polymer-cement ratio and antifoamer content. The water absorption and chloride ion penetration improvement is attributed to the improved bond between cement hydrates and aggregates because of the incorporation of redispersible polymer powder.