• Journal of the Korea Concrete Institute
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• v.19 no.5
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• pp.539-547
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• 2007

The effects of binder and alumina content on the setting time, drying shrinkage, strength, freezing and thawing resistance and water absorption of polymer-modified pastes with alumina powder were examined. As a result the setting time of the polymer-modified pastes with alumina powder tended to delay with increasing binder content. Irrespective of the type of polymer, the drying shrinkage of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina powder content. Regardless of the type of polymer, the tensile and adhesion strengths of the polymer-modified pastes with alumina powder tended to increase with increasing binder content and alumina powder content. Irrespective of the type of polymer, the durability factors of the polymer-modified pastes with alumina powder tended to increase with increasing alumina content. Irrespective of the type of polymer, the water absorptions of the polymer-modified pastes with alumina powder tended to decrease with increasing binder content and alumina content.

• Journal of the Korea Organic Resources Recycling Association
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• v.12 no.4
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• pp.95-104
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• 2004

A styrene solution of waste expanded polystyrene with a crosslinking agent and an initiator was used as a binder for waste wood-plastic composite panels. The waste wood-plastic composite panels are prepared with various binder contents and filler-binder ratios by using a hot press molding method. The apparent density of the composite panels is increased with increasing binder content and filler-binder ratio, while their water absorption and expansion in thickness are decreased with increasing binder content and filler-binder ratio. The maximum flexural strength and wet flexural strength of the composite panels are obtained at a binder content of 35% and a filler-binder ratio of 0.8. Decreases in the flexural strengths of the composite panels due to water immersion at 20 and $100^{\circ}C$ are hardly recognized at binder contents of 30% or more.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.361-362
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• 2010

Six alkali-activated(AA) concrete mixes were tested to ascertain the effect of unit binder content on the slump and compressive strength of concrete. Test results showed that the compressive strength of AA-concrete increased with the increase of the unit binder content, while the increasing rate was lower that recorded in ordinary portland cement concrete.

• Magazine of the Korea Concrete Institute
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• v.10 no.1
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• pp.101-108
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• 1998

시멘트 대체재로 사용하는 플라이애쉬(0, 10 , 30 ,50 %)를 혼입한 콘크리트의강도발현을 관찰하기 위해 각각 21$^{\circ}C$에서 수중양생과 85$^{\circ}C$에서 증기양생방법을 채택하여 실험하였다. 수중양생한 보통 콘크리트는 플라이애쉬 혼입량이 증가할수록 조기재령에서는 낮게 강도발현을 하였으나. 28일 압축강도를 기준으로 하여 물.시멘트비를 변화한 배합비(결합재량 증가)의 실험결과는 조기강도발현이 향상되었다. 특히 플라이애쉬를 30%혼입한 콘크리트는 우수하게 강도발현을 하였다. 그리고 동일한 28일 압축강도를 갖는 배합비(결합재량 증가)에서 증기양생한 플라이애쉬콘크리트는 보통콘크리트보다 강도발현이 비슷하거나 향상되었으며, 양생온도는 플라이애쉬콘크리트의 강도발현에 많은 영향을 미치는 것으로 관찰되었다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.953-956
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• 2008

The purpose of this study is to ascertain the void ratio, permeability coefficient and compressive strength of porous polymer concretes with unsaturated polyester. The porous polymer concretes using unsaturated polyester with polymer binder contents of 3.5, 4.0, 4.5 and 5.5% are prepared, and tested for void ratio, permeability coefficient and compressive strength. As a result, void ratio and permeability coefficient of porous polymer concrete decrease with increasing polymer binder content. However, the compressive strength of porous polymer concrete increase with increasing polymer binder content. The compressive strength of porous polymer concrete decrease with increasing permeability coefficient.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.5
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• pp.85-92
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• 2016

The eight mixes and artificial soil aggregates were prepared for evaluating the practical application of lightweight foamed concrete as soil aggregates. The main parameter was unit binder content ranged between from 100 to $800kg/m^3$. In lightweight foamed concrete, flow, slurry and dried density, and compressive strength at different ages were measured. In Artificial soil aggregates crushed from lightweight foamed concrete, particle size distribution, pH, coefficient of permeability, cation exchange capacity(CEC), and ratio of carbon to nitrogen(ratio of C/N), were measured. The test results showed that flow, slurry and dried density, and compressive strength at different ages of lightweight foamed concrete increased with the increasing of unit binder content. Compressive strength at age of 28, of lightweight foamed concrete with unit binder of more than $500kg/m^3$, was more than 4 MPa. The ammonium phosphate immersion time of more than age of 3, was effective to decrease pH of artificial soil aggregates. In addition, artificial soil aggregates was evaluated as high class in terms of cation exchange capacity(CEC), while satisfied with value of ratio of carbon to nitrogen(ratio of C/N) recommended by landscape specification.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.1
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• pp.64-71
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• 2015

Silica fume is generally adopted as admixture for Ultra High Strength Concrete (UHSC) owing to its remarkable contribution to the strength and durability but increases significantly the fabrication cost of UHSC. Accordingly, this study investigates the replacement of silica fume by blast furnace slag (BS) and fly ash (FA) in order to lower the fabrication cost of 80MPa-UHSC. To that goal, experiment is conducted on the mix proportions of mortar in terms of its binder combination, water-to-binder ratio (W/B) and unit binder content. Based on the experimental data, a mix design of concrete is derived and its properties are verified. The results reveal that a W/B of 21% and unit binder content of $720kg/m^3$ are appropriate to achieve 80MPa-UHSC using a binder composed of 60% of OPC, 30% of BS and 10% of FA. The properties of the corresponding UHSC are seen to be satisfactory with a slump flow of 715mm and compressive strength of 97MPa at 28days. The application of the binder combination derived in this study is analyzed to reduce the cost by 50% of binder compared to the mix using silica fume while realizing equivalent performance.

• Journal of the Korean Geosynthetics Society
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• v.18 no.2
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• pp.37-44
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• 2019

The compressive strength of the soil stabilizer in the deep mixing method (DMM) depends on kinds of soil, particle size distribution, and water content. Because of this, Laboratory test has to perform to estimate the unit weight of binder to confirm the satisfaction of the design strength. In this study, uniaxial compression strength was measured by mixing the soil stabilizers developed in the previous study with clay in Busan, Yeosu, and Incheon area. And the strength enhancement effect was evaluated comparing with blast furnace slag cement (BFSC). Also, the relationship between the unit content of binder and uniaxial compressive strength was investigated in order to easily calculate the unit weight of binder required to ensure the stability of the ground at the field. As the results of the analysis, the relationship between the unit content of binder and the uniaxial compressive strength are ${\gamma}_B=(108.93+0.0284q_u){\pm}35$ when W/B is 70%, and ${\gamma}_B=(122.93+0.0270q_u){\pm}40$ when W/B is 80%.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.19-20
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• 2015

In this research, by examining the influence that high quality fine aggregate and low quality fine aggregate have on the strength of concrete through tests, the manifest strength of concrete according to high quality fine aggregate was reviewed. The results showed that compared to low quality fine aggregate usage mixture, the unit volume to achieve the same liquidity decreased and accordingly the W/B also decreased therefore increasing the strength of concrete, and as high quality fine aggregate was used, it is determined that there can be improvements to the economically feasibility of usage mixture and improvement in durability etc.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.585-593
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• 2021

This study investigates the compressive strength of high-strength cement composites with 64 mixture designs and 2 curing conditions. The cement composites were designed with varying water-to-binder ratios, silica fume content to cement, and binder content per unit volume of cement composite to explore compressive strength development depending on its mix design. An increase in the water-to-binder ratio decreased the compressive strength of the composites, having consistency with the trend in normal concrete. The compressive strength increased with ages at an ambient curing temperature, but it was not identified at high-temperature curing. The compressive strength development was negligible in case that silica fume content to OPC is 15%~25%, but a decrease in the con ten t below 15% reduced compressive stren gth. It was more obvious in the specimen of low water-to-binder ratio. The specimen with 840kg/m³ of binder content per unit volume had the highest compressive strength in this study, and the decrease in binder content reduced the compressive strength of high strength cement composites in low silica fume content.