• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
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• pp.366-372
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• 1996

This paper persents the characteristics and properties of the five domestic and foreign-made anti-washout admixtures commercially available in Korea. These admixtures have been analysed by experiments to compare among others specifically on the following items : air content, slump-flow, hardening time, pH, filling condition, turbidity, content of chloride, compressive strength of underwater concrete and ratio of ambient / underwater concrete compressive strength. The mix design for comparison has been set according to the Japanese practicesince there is still no guideline concerning underwater concrete available domestically.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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• pp.179-180
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• 2015

Recently, admixture manufacturers have improved the performance of admixtures to solve problems caused by high viscosity of high performance admixtures, and accordingly, it is expected to affect fluidity of concrete using admixtures. Therefore, in this research, how each kind of HAE affects consistency curve of cement mortar was examined.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.299-304
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• 2002

This research was to investigate the invasion and diffusion properties of chloride ion on the concrete containing mineral admixtures by the electrically accelerated test. Mineral admixtures selected in mixes were fly-ash, ground granulated blast-furnace slag, silica fume, and meta-kaolin with 3 degrees of replacement ratios. Tang and Nilsson's test method was used to estimate chloride diffusion coefficients of that mixes. As a result, the total current passing charge and the diffusion coefficient of chloride ion were reduced with the use of mineral admixtures and the increase of replacement ratios. In addition, compressive strength was related with diffusion coefficient of chloride ion. Diffusion coefficients of concrete mixed with ground granulated blast-furnace slag showed relatively low value under the range of compressive strength of 400㎏f/㎠.

• 한국농공학회논문집
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• 제47권3호
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• pp.41-48
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• 2005

The purpose of this study is to improve the performance of jet set cement, which mixed with the mineral admixtures such as silica fume, fly ash and ground granulated blast furnace slag. First, the test of mortar according to the substitute ratio of mineral admixtures were evaluated. And then using it obtained from test results, it was conducted with experiment of mechanical, physical and permeable characteristics of concrete. Laboratory test results showed that concrete substituted for $5\%$ of silica fume didn't have an effect on prominent performance relating to compressive strength. However it was superior to concrete in case of resistance of chloride permeation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.281-282
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• 2009

본 연구에서는 산 및 황산염 저항성에 미치는 광물질 혼화재의 영향을 평가하기 위한 것이다. 이를 위하여 물-결합재비 32% 및 43%에 대해서 광물질 혼화재 종류에 따라 이들을 혼입한 콘크리트 공시체를 제작하였다. 재령 182일 동안의 침지실험 결과로부터, 콘크리트의 산 및 황산염에 대한 저항성은 광물질 혼화재를 혼입한 콘크리트가 플레인 콘크리트보다 훨씬 우수한 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.271-276
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• 2003

This study is about the rheological properties of cement slurry using admixtures. The variables are the type of cement(Type I, II, IV, V) and the substitution ratio of admixtures such as fly ash and slag. As a result of measuring the fluidity of various types of cement slurry at the early stage, type 2, type 4 and type 5 showed the similar property. The fluidity of type 1 and ternary blended cement was low. it is thought that it is because of the high $C_3$A content. The cement slurries containing mineral admixtures were superior in the property of fluidity retention.

• 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.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2004년도 학술대회지
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• pp.51-54
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• 2004

This paper investigated the results of mixture proportion and compressive strength of concrete incorporating mineral admixtures. W/B and contents of mineral admixtures were selected as test parameters. According to test results, use of mineral admixtures resulted in a reduction of fluidity and air contents caused by increased fine particles and absorption effect of FA on reduction of AE agent. Thus, increase of SP and AE agent was needed to maintain the same fluidity and air content as plain concrete. At early stage, use of CKD was beneficial to the compressive strength while at 28days. incorporation of FA and BS had favorable effect on the compressive strength.

• Structural Engineering and Mechanics
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• 제51권3호
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• pp.403-412
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• 2014

In this paper, enhancement of corrosion and chloride resistance of high performance self compacting concrete (SCC) through incorporating nanosilica into the binder has been investigated. For this purpose, different mixtures were designed with different amounts of silica fume and nano silica admixtures. Different binder contents were also investigated to observe the binder content effect on the concrete properties. Corrosion behavior was evaluated by chloride penetration and resitivity tests. Water absorption and capillary absorption were also measured as other durability-related properties. The results showed that water absorption, capillary absorption and Cl ion percentage decreased rather significantly in the mixtures containing admixtures especially blend of silica fume and nano silica. By addition of the admixtures, resistivity of the SCC mixtures increased which can lead to reduction of corrosion probability.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.22-23
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• 2017

The purpose of this study is to ascertain self-healing function on microcracks in bisphenol F-type epoxy-modified mortars using expansive admixtures. The specimens are prepared with various polymer-binder ratios of 0, 5, 10, 20%, expansive admixture contents of 0% and 10%, a sodium carbonate content of 0.25%, and subjected to exposure conditions of CR1, CR2, CR3 and CR4. The specimens are tested for self-healing effect, porosity and FE-SEM analysis. As a result, self-healing effects of bisphenol F-type EPMMs with expansive admixtures are visible in all of the outdoor exposure conditions. In particular, exposure conditions of CR3 and CR4 are most noticeable. And the porosity of EPMMs is reduced with an increase in the polymer-binder ratio, and is considerably smaller than that of unmodified mortar.