• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.519-523
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• 1996

Calcium hydroxide produced by cement hydration decreases the durability and the compressive strength of cement mortars. Pozzolanic property of meta kaolin and silica fume allows to avoid this drawback. Calcium hydroxide consumption according to pozzolanic raction is evaluated by Fourier differential thermal analysis. Particulary the properties of high performance and high strength of cement mortar containing above 10% meta kaolin and silica fume were resulted in the pozzolanic activity.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.905-908
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• 2006

In this study examines physical and mechanical properties the use of domestic low grade meta-kaolin in light weight porous concrete. For this purpose light weight porous concrete incorporating low grade meta-kaolin admixture, was tested for tensile strength and acoustic characteristics. Checking tensile strength of cement and low grade meta-kaolin mixture was used to determine the optimum mix proportion of the low grade meta-kaolin admixture. In this paper sound absorbing material has been investigated by using the light weight porous concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.360-363
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• 2004

The effectiveness of Meta-Kaolin to prevent detrimental expansion due to alkali-silica reaction was investigated through the ASTM C 1260 method. Reactive aggregate used is a metamorphic rock. The replacement proportions of portland cement by Meta-Kaolin were 0, 5, 10, 15, 25 and 35 percent, respectively. The results indicate that 25 percent replacement of portland cement by Meta-Kaolin seems to be most effective to reduce alkali-silica reaction expansion under this experimental conditions.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.425-428
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• 2005

In this study, the experiment was carried out to investigate and analyze the strength properties and flowability of concrete using meta kaolin. The main experimental variables were water/binder ratio 40.0$\%$, water content 170kg/$m^{3}$ and mineral admixtures such as slag powder, silica fume and meta kaolin. According to the test results, the principle conclusions are summarized as follows. 1) The flowing property of concrete that uses meta kaolin appears to be the same to that of the silica fume concrete, but the slump flow that evaluates the compaction ability of concrete shows the most favorable performance. 2) The air content of the concrete that uses meta kaolin can be effectively controlled for the target performance in compliance with the use of AE agent. 3) When it comes to the strength of concrete that uses meta kaolin, the most favorable development of strength occurs when the replacement rate is 10$\%$, in case of the silica fume, and the slag power. In addition, as the replacement rate increases, so becomes the development of concrete strength favorable.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.05b
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• pp.239-242
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• 2009

As the high-rise building increase due to the gravitation of population to big cities recently, it requires high quality and high performance of Concrete. As a result, people are keenly interested in Meta-kaolin as new admixture favorable from an economic perspective, which has strength and endurance with admixture at the same level like Silica-fume. Accordingly, as to Meta-kaolin, this study was to set by three levels like domestic one, foreign one, and Silica-fume, the water-binding material ratio 25%, and four level substitute like 0, 10, 20, and 30(%) in order to compare and analyze the quality durability of high-concrete according to the substitute of Meta-kaolin applicable with replacement of Silica-fume. As a result of performing experiment it was found that when water-binding material ratio increases, resistance of neutralization, carbonation, salt damage and sulfate decrease, and when replacement ratio of mineral admixture increases, depth of accelerating carbonation gets greater. Also, the combination of SF and MK-B favored resistance to chloride ion penetration better than MK-A, and it was found that when replacement ratio of binding material increases, the resistance to sulphuric acid increases. Therefore, based on this study, it was understood that meta-kaolin is useable in replacement of silicafume.

• Journal of the Korea Concrete Institute
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• v.20 no.3
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• pp.307-315
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• 2008

In this study, it is investigated the properties of high strength concrete using mineral admixture, on the purpose of use of meta kaolin for the substitutive materials to silica fume which is so expensive. The plain mixtures are 3 degrees which are ordinary portland cement, blast furnace slag cement and OPC included fly ash 20%, and silica fume and meta kaolin are substituted for the each plain mixtures in the range of 20%. The results of experiment showed as follows. In case of silica fume was only used, the viscosity and slump flow of fresh concrete were much decreased, on the contrary air content increased. But as usage of meta kaolin increased, to being increase the viscosity of fresh concrete, slump flow increased and air content and usage of super-plasticizer were decreased. Accordingly the workabilities of concrete were against tendency between silica fume and meta kaolin. The compressive strength, velocity of ultrasonic pulse and unit weight were increased according to usage of meta kaolin, the properties of hardened concrete were judged that they are affected with air content of fresh concrete, so it is very important to control air content of high strength concrete. Therefore, the use of meta kaolin is prospected to the substitutive material of silica fume, in case of using silica fume and meta kaolin, it is judged that the optimum usage of silica fume and meta kaolin is about 10% respectively, considering workability and strength of concrete.

• Korean Journal of Materials Research
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• v.20 no.9
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• pp.488-493
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• 2010

Geopolymer is a term covering a class of synthetic aluminosilicate materials with potential use in a number of areas, but mainly as a replacement for Portland cement. In this study, geopolymers with fly ash and meta kaolin were prepared using KOH as an alkali activator and water glass. The effect of water glass on the microstructures and the compressive strength of the geopolymer was investigated. As the amount of water glass increased, the dissolved inorganic binder particles in the geopolymers increased due to polymerization, resulting in a dense microstructure. The meta kaolin-based geopolymer showed a better extent of polymerization and densification than that of the fly ash-based geopolymer. XRD data also suggested that polymerization in meta kaolin-based geopolymers should be active resulting in the formation of an amorphous phase with an increasing amount of water glass. The compressive strength of the geopolymer was also dependent on the amount of water glass. The compressive strength of the geopolymers from both fly ash and meta kaolin increased with an increasing amount of water glass because water glass improved the extent of polymerization of the inorganic binder and resulted in a dense microstructure. However, the addition of water glass to the geopolymer did not seem to be effective for the improvement of compressive strength because the meta kaolin-based geopolymer mainly consisted of a clay component. For this reason, the fly ash-based geopolymer showed a higher value of compressive strength than the meta-kaolin geopolymer.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.263-264
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• 2010

In this study, respectively and furnaced kaolin at $900^{\circ}C$ was also manufactured into meta kaolin by air cooling and water cooling method. The chemical characteristic and mechanical properties of various type of blended cements contained above mentioned gypsum and meta kaolin materials analyzed and compared with those characteristics of cement matrix with silica fume. From the test, the cement mixed meta kaolin made in water cooling has more excellent quality than other material.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.89-90
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• 2010

As a result of physical characteristics of using meta-kaolin and alkali accelerator, it was found that higher curing temperature density is favorable to strength development at early age and the higher the age is, the higher, most of the compressive strength gets. Also, I was shown that more than atmospheric curing, steam curing was favorable for development of compressive strength. When the temperature of curing temperature was higher, most of the compressive strengths were higher. Thus, based on this study, it was understood that environmental-friendly chemically combined concrete using meta-kaolin and alkali accelerator can be utilized without using cement.

• Journal of the Korean Ceramic Society
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• v.47 no.3
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• pp.223-231
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• 2010

The serious issue of tall building is to ensure the fire-resistance of high strength concrete. The fire resistant finishing method is necessarily essential in order to satisfy the fire resistance time of 3 h required by the law. The fire resistant finishing method is installed by applying a fire resistant material as a method of shotcrete or a fire resistant board to high strength concrete surface. This method can reduce the temperature increase of the reinforcement embedded in high strength concrete at high temperature due to the installation thickness control. This study is interested in identifying the effectiveness of inorganic alumino-silicate compounds including the inorganic admixture such as fly ash and meta-kaolin as the fire resistant finishing materials through the analysis of fire resistance and components properties at high temperature. The study results show that the fire resistant finishing material composed of fly ash and meta-kaolin has the thermal stability of the slight decrease of compressive strength at high temperature. These thermal stability is caused by the ceramic binding capacity induced by alkali activation reaction by the reason of the thermal analysis result not showing the decomposition of calcium hydrate. Inorganic compounds composed of fly ash and meta-kaolin is evaluated to be very effective as the fire resistance material for finishing to protect the concrete substrate by the reason of those simplicity in both application and manufacture. The additional study about the adhesion in the interface with concrete substrate is necessary for the purpose of the practical application.