• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
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• pp.433-436
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• 2005

The Fly-ash makes an Alumino-silicate gel when it mixes an alkali or a silicate solution. This Alumino-silicate gel is produced to the activation of an alkali silicate. And this act to the binder and makes a combine of particles. This study involved mechanical strengths of an Alumino-silicate Gel based the Fly-ash with an alkali solution. NaOH, KOH were utilized to an alkali solution. The alkali solution concentration was varied from 6 to 12M and the some added also the Meta-kaolin, Waterglass so that it made high the mechanical performance. Based on the experimental result, the compressive strengths increased as the quantity of the Meta-kaolin increased. And a mechanical strengths appeared according to the concentration of an alkali solution so that it was different. XRD, FT-IR have been used to characterize mechanical performance.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.200-201
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• 2013

This study is interested in manufacturing the concrete surface impregnants including tetra ethyl ortho silicate, alkali silicate for the repair of the exposed concrete and the color concrete requiring the advanced function in view of the concrete appearance. The surface layer change and porosity properties was tested for the review of application. The result of this study show that the effective silicate are tetra ethyl ortho silicate and alkali silicate t. The adhesion in tension is slightly increased but the reinforcement of concrete substrate is slight. So, the concrete impregnant of this study is more desirable for the improvement of durability rather than the reinforcement.

• 한국농공학회논문집
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• 제46권3호
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• pp.65-72
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• 2004

Modern underground and tunnel works that the wet type shotcrete is getting widely designed and applied in a large scale project. Further to its applications, the needs of improving the performance of the shotcrete, such as new and developed additives and accelerators fur increasing the performance of shotcrete, become the most important issue in the field. The main objective of this study evaluated to performance of steel fiber reinforced shotcrete using alkali free based accelerator for the durability and high quality of shotcrete. The major test variables are accelerator type and its dosage. One type silicate based accelerator and one type aluminate based accelerator and one type alkali free based accelerator were used. The dosage of accelerators is determined by the manufactures and laboratory test condition. Compressive strength test results showed that the dosage of silicate and aluminate based accelerators caused reduction of mechanical properties of shotcrete. Compressive strength of alkali free based accelerator is more stable than of silicate and aluminate based accelerators. Also, according to the compressive strength and flexural test results, it was found that steel fiber reinforced shotcrete used alkali free based accelerator could attain significant improvement in the mechanical and flexural performance.

• 한국안전학회지
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• 제8권2호
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• pp.30-38
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• 1993

To increase fire proofing characteristics of protective coating based on soluble alkali silicate, silicate coatings were studied on thermal properties, IR spectroscopy, solubility and intumescence. Intumescence and solubility of the samples were dependent on the strength of cationic cross-links between polysilicate particles. The degree of intumescence and solubility decrease K-silicate > Na-silicate > Li-silicate in the order. Especially Si$_2$O$_{5}$ $^{-2}$ crystalline regions were found to exist in Potassium silicate sample. Mixture of two kinds of silicate, for example, Lithium silicate when added to sodium silicate or potassium silicate was find to significantly reduce efflorescence and increase water resistance. This appears to be a result of stronger crosslinking between polysilicate particles by the small lithium cation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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• pp.111-117
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• 1995

The alkali-aggregate reaction is a reaction between the alkali metals in the pore water of a concrete and an unstable mineral of the aggregate. There are three types of alkali-aggregate reation which causes deterioration of concrete, such as alkali-silicate reation, alkali-carbonate reaction and alkali-silica reation. Deterioration due to alkali-silica reation is more comon than that due to either the alkali-silicate or alkali-carbonate reaction. The alkali-silica reation is a reaction between the hydroxyl ions in the pore water of a concrete and silica which exists in signigicant quantities in the aggregate. In this PAPER, Alkali-aggregate reactions of mortar made with various abroad aggregate were investigated using XRD, microscope, chemical and physical tests. In additions, the effects of the texture of aggregate, Na, K, CI ion concentrations added to the mortar, on these reactions were studied.

• 한국안광학회지
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• 제1권1호
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• pp.1-14
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• 1996

Magic-Angle-Spinning NMR에 나타나는 $Li^+$ 이온의 운동과 관련된 알칼리 혼합 효과에 미치는 전이금속 산화물의 영향을 조사하기 위하여 불순물 $Fe_2O_3$를 0.1 mol% 첨가시킨 혼합 알칼리 Silicate 유리들을 제조하였고, 온도에 따라 $^7Li$ MAS-NMR 스펙트럼과 상온에서 $^7Li$ 스핀-살창 완화시간을 측정하였다. $Fe_2O_3$가 첨가되었을 때, 스펙트럼의 선폭이 조금 변화되었을 뿐이며 선 모양이 거의 변하지 않고 있다. 이 때문에, 스핀-스핀 완화 과정에서는 혼합 알칼리 효과가 충분히 나타나는 것으로 불수도 있지만 반드시 그렇지만은 않아 보인다. $Li^+$ 이온의 활성화 에너지가 혼합 알칼리 유리에서 오히려 감소하는 경향이 나타났다. 이것은 혼합 알칼리 효과가 아니다. 스핀-살창 완화시간, 완화 과정 분석을 통한 $Li^+$ 이온의 확산 환경, 그리고 핵 자가화 (nuclear magnetization) 등의 비교에 의하면, $^7Li$ 스핀-살창 완화 과정에서 알칼리 혼합 효과는 거의 나타나지 않는 것을 확인 할 수 있었다.

• 한국세라믹학회지
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• 제45권11호
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• pp.719-724
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• 2008

Every concrete structure should continue to perform its intended functions such as to maintain the required strength and durability during its lifetime. Deterioration of the concrete structure, however, occurs more progressively from the outside of the concrete exposed to severe conditions. Main deteriorations in concrete structures result from carbonation, chloride ion attack and frost attack. Concrete can therefore be more durable by applying surface protection to increase its durability using impregnants, which are normally classified into two large groups in polymeric and silicate materials. Concrete impregnants are composed of silanes and alkali silicates (sodium, potassium and lithium silicate). Thus, this study is concerned with elevating the carbonation and Cl- penetration resistance of concrete structures by applying alkali silicate hydrophilic impregnants including lithium and potassium silicates. From the experimental test results, lithium and potassium silicates produced a good improvement in carbonation resistance and are expected to be used as hydrophilic impregnants of concrete structures.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2007년도 추계 학술논문 발표대회
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• pp.91-94
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• 2007

It is essential every concrete structure should continue to perform its intended functions, that is maintain its required strength and durability, during the service life. However, deterioration occurs more progressively from the outside of concrete exposed to severe conditions. Deterioration in the concrete structure is due to carbonation and chloride ion attack. Therefore, concrete structure is needed to surface protection for increase durability using impregnant. Impregnant classify into two large groups in polymeric and silicate materials. Silicate impregnant is included silane and alkali silicate(sodium and lithium silicate). Thus, this study is concerned with carbonation and chloride ion resistance of self cleaning hydrophilic impregnant of concrete structure using lithium and potassium silicate. From the experimental test result, lithium and potassium silicate have a good properties as a carbonation and chloride ion resistance. Lithium and potassium silicate make good use of hydrophilic impregnant.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.63-70
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• 2000

In 1925, H.J. Joosten was the first in the world to use chemical injection grouts composed of sodium silicate and calcium chloride. This unique development prompted the introduction of other chemical grouting techniques. Among these chemical grouting techniques, sodium silicate based grout has been the most widely used in the world, but it has not been generally considered to be a permanent material. Therefore, studies to improve the weak points of sodium silicate based grout have been conducted, and new applications of grout were recently developed. We also developed the micro fine hybrid silicate grout of suspention type which properties are sepecialized as the high strength and durability, according to the reactant of special sodium silicate grout and the high strength hardener. As the results of this study we could derive the 2 times over high strength of Micro fine hybrid Silicate grouting method(MS method) more than that of the ordinary sodium silicate grout. And also we could confirm that the alkali leakage of micro fine hybrid silicate grout is less than that of ordinary sodium silicate grout. So we could get the high strength and durability of hybrid silicate grout are superior to those of ordinary sodium silicate grout.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.731-736
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• 2003

Alkali silicate system has wide application to accelerating admixture for shotcrete, but it has several problems that decrease long-term strength and delay setting time. So alkali-free system was gradually focused on accelerating admixtures for shotcrete due to its environmental property. The aim of this study is to investigate effect of alkali-free accelerating admixtures on aluminum sulfate system containing diethanolamine or acrylic acid etc. The alkali-free accelerating admixture has better properties than silicate system accelerating admixtures on compressive strength and low pH as shotcrete. Especially, the compressive strength of alkali-free accelerating admixture containing diethanolamine was increased about 10% compared with the value of ordinary portland cement.