• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.569-574
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• 2002

Generally, the limestone powder is known to have some advantages in rheology of fresh concrete, resistance of material separation, and enhancement of strength at early ages. Recently, great attention is being paid to limestone blended cements in the manufacture of concrete, especially in the countries of Europe. The purpose of the present study is to establish the mechanical and durable properties of concrete containing slag and limestone powder. In this paper, the chloride ion penetration test, rapid carbonation test and rapid freezing-thawing test is carried out to study durability of concrete with various content of limestone powder. Futhermore, the strength of concrete is evaluated with various ages.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.201-206
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• 2002

The purpose of this study is to improve the anti-corrosive properties of coated reinforcing bar using polymer cement slurry. Poymer cement slurry are prepared with three types of polymer dispersions and corrosion inhibiting admixture. And tested for corrosion accelerating tests such as immersion in NaCl 10% solution NaCl 10% solution spray, high temperature and pressure steam in condition of 8cycles, carbonation before and after, penetration of NaCl solution. From the test results, it is concluded that the anti-corrosive properties are considerably improved by coating using polymer cement slurry at surface of reinforcing bar. And this trend is marked by adding of corrosion inhibiting admixture. The difference of the anti-corrosive properties is hardly recognized according to types of polymer dispersions. The anti-corrosive properties of coated reinforcing bar using polymer foment slurry are improved to a great extent compared to those of plain reinforcing bar accordiy to increasing content of chloride ion in cement concrete.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2002년도 학술발표회 발표논문집
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• pp.153-156
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• 2002

The purpose of this research was to evaluate on the properties of fresh and hardened high-performance concrete(HPC) incorporating high-reactivity metakaolin(HRM). Setting time, heat of hydration, compressive strength, resistance to chloride-ion penetration, and repeated freezing and thawing test were carried out in order to investigate the properties of fresh and hardened state concrete. The properties of the HRM concrete were also compared with those of the portland cement concrete and silica fume(SF) concrete. The laboratory test results indicate that HRM material can be used as a supplementary cementitious material to produce high-performance concrete.

• 한국안전학회지
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• 제31권4호
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• pp.82-89
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• 2016

In this paper, various of experiments were performed for checking the usefulness of Pozzolan Inorganic Polymer(PIP) Waterproof Admixture. The results of the experiment enabled to set the optimum mixture ratio of PIP waterproof admixture as 3.5%. Then, the test specimen mixed with PIP waterproof admixture was produced and consider whether meeting the quality standard of waterproofing admixture for concrete (KS F 4926) From the results, all the items such as mechanical properties and durability were meet the quality standard of KS. The PIP waterproof admixture concrete shows the high resistance of absorption, permeability and chloride ion penetration thanks to its internal components such as siliceous powder, zinc stearate and dispersive polymer.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.123-128
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• 1999

Recently, as a performance based design concept is introduced, assurance of expected performances on serviceability and safety in the whole span of life is exactly requested. So, quantitative assessments about durability related properties of concrete in early-age long term are come to necessary, Especially in early age, deterioration which affects long-term durability performance can be occurred by hydration heat and shrinkage, so development of reasonable hydration heat model which can simulate early age behavior is necessary. The micor-pore structure formation property also affects shrinkage behavior in early age and carbonations and chloride ion penetration characteristic in long term, So, for the quantitative assessment on durability performance of concrete, modelings of early age concrete based on hydration process and micor-pore structure formation characteristics are important. In this paper, a micromechanics based hydration heat evolution model is adopted and a quantitative model which can simulate micro-pore structure development is also verified with experimental results. The models can be used effectively to simulate the early-age behavior of concrete composed of different mix proportions.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.467-470
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• 2005

This study reports the properties of high early strength & durability of concrete using PC admixture. To apply these data to construction site, we did the lab tests. The target of this study is to accomplish early strength of concrete(5.0 MPa/18 hr), and we did the durability tests such as length change test, chloride ion penetration test, adiabatic test, etc. PC type was more excellent than PNS type admixture. According to these tests, we concluded that we can apply this type of PC admixture to the civil & construction site, and we can reduce the term of works and finally we can accomplish the economical construction.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.307-308
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• 2009

부산 롯데타운용 80MPa급 초고강도 콘크리트는 낮은 W/B와 높은 결합재량에 기인하여 수화생성 물이 증가하고, FA 및 BS의 포졸란 및 잠재수경성반응에 의하여 생성된 C-S-H겔이 공극구조를 개선함으로써 콘크리트 내부조직이 밀실하게 형성되어 탄산가스, 염화물 및 염소이온의 침투가 없는 것으로 나타나 내구성은 매우 우수한 것으로 판단된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2009년도 춘계 학술대회 제21권1호
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• pp.535-536
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• 2009

본 연구에서는 역학적으로 휨, 인장 및 압축파괴 시에 인성이 대폭적으로 향상됨은 물론, 휨응력 하에서도 다수의 균열 분포되는 특성을 가지고 있는 DFRCC의 내구성능을 평가하고자 한다. 따라서 DFRCC의 내구성능을 평가하기위해 염화물 촉진시험 및 동결융해시험을 실시하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 가을 학술발표회 논문집
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• pp.78-81
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• 2003

Recently, physical properties of concrete containing ternary blended cement were actively researching to develop durability, mobility, and atc. as well as strength increase of concrete. In this study, durability of concrete such as the resistance against chloride ion penetration, rebar corrosion, freeze and thaw, and sulfate were researched for concrete containing ordinary portland cement(OPC) and ternary blended cement(TBC), respectively. For this purpose, concrete specimens containing OPC and TBC, respectively, were made for 37.5% of W/C, and then various durability experiments described above were carried out. As a result, it was observed from the test that concrete containing TBC showed excellent durability than concrete containing OPC.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.201-202
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• 2010

본 연구는 육상모래를 사용한 70, 100MPa급 고강도 콘크리트를 현장 배처플랜트를 이용하여 제조하고 강도발현 상태를 파악하고 이들의 내구특성을 검토하기 위하여 제조된 콘크리트에 대해 동결 융해, 탄산화, 염해저항성 실험을 실시하였다.