• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.55-56
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• 2022

As global warming becomes serious, research is continuously being conducted to reduce CO2 emissions. Among building materials, the carbon emission of cement is so high that it accounts for 6.8% of the carbon emission of the entire industry. Studies replacement of cement with blast furnace slag and fly ash are steadily increasing. In addition, efforts are being made to reduce air pollution due to increased damage caused by increased concentrations of harmful substances such as fine dust and heavy metals in the air. There is an increasing number of studies that enable adsorption by mixing adsorbents into building materials. This study reviewed the strength properties to make an adsorbable non-cement finishing material by mixing tourmaline, an adsorbent, based on the non-cement composite, and confirmed that the strength decreases as the replacement ratio increases.

• Advances in concrete construction
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• v.5 no.3
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• pp.271-288
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• 2017

This paper aims to investigate the effects of replacing cement with ground granulated blast furnace slag (GGBFS) in self compacting concrete in the fresh and hardened state. The performance of SCC in moderate climate is well investigated but few studies are available on the effect of hot environment. In this paper, the effect of initial water-curing period and curing conditions on the performance of SCC is reported. Cement was substituted by GGBFS by weight at two different levels of substitution (15% and 25%). Concrete specimens were stored either in a standard environment (T=$20^{\circ}C$, RH=100%) or in the open air in North Africa during the summer period (T=35 to $40^{\circ}C$; R.H=50 to 60%) after an initial humid curing period of 0, 3, 7 or 28 days. Compressive strength at 28 and 90 days, capillary absorption, sorptivity, water permeability, porosity and chloride ion penetration were investigated. The results show that the viscosity and yield stress are decreased with increasing dosage of GGBFS. The importance of humid curing in hot climates in particular when GGBFS is used is also proved. The substitution of cement by GGBFS improves SCC durability at long term. The best performances were observed in concrete specimens with 25% GGBFS and for 28 days water curing.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.04a
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• pp.215-220
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• 1994

본 연구의 목적은 당사 콘크리트 배합설계 프로그램인 쌍용배합설계시스템(Ssangyong Mix Proportioning Design System ; 이하 SMPD라 칭한다)을 기본으로해서 슬래그시멘트에 대한 콘크리트 배합설계(안)을 제안함으로써 콘크리트 현장에서 합리적으로 콘크리트를 제조할 수 있도록 하는데 있다. 연구 내용은 슬래그시멘트와 보통시멘트간의 콘크리트 물성차이를 실험실적으로 규명하기 위해서 슬래그 함유량 및 양생 온도별로 슬래그시멘트의 콘크리트 강도발현특성, 물시멘트비, 단위수량변화 및 응결특성 등을 검토하였으며 그 결과를 이용하여 슬래그시멘트의 콘크리트 배합설계를 시행, 표준배합과 현장배합표를 제시하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.156-159
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• 2003

Large amount of binders and high-range AE water-reducing (HRWR) agent are required for self-consolidating concrete in order to achieve flowability and segregation resistance. In this study, the initial permeability of SSC(self-consolidating concrete) until the age of 28 days is measured and compared with those of other SSCs, in which some parts of cement are substituted with fly ash or blast furnace slag. The strengths of SSC samples are also examined along with the permeability change.

• Proceedings of the Korea Contents Association Conference
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• 2013.05a
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• pp.101-102
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• 2013

시멘트 및 건설산업은 그 제조과정에서 다량의 이산화탄소를 배출하기 때문에 지구온난화 문제를 가속화시키고 있는 것으로 알려져 있다. 따라서 이러한 시멘트를 대체할 수 있는 재료 개발에 많은 연구가 이루어지고 있으며, 철강산업 부산물인 고로슬래그 미분말은 그 중 하나의 재료라 할 수 있다. 고로슬래그 미분말은 물과 직접 반응하지 않으나 알칼리 환경하에서는 물과 반응하여 CSH 수화물을 생성하게 된다. 본 연구에서는 알칼리 자극제를 첨가한 경우의 무시멘트 경화체에 대한 강도 및 수화 특성에 대하여 분석하고자 하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.335-340
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• 1997

The mineral admixtures, ground granulated blast furnace slag (GSB) and fly ash (FA), were mixed with ordinary portland cement(OPC) in order to reduce temperature rise and slump loss in concrete. In according to concrete replaced with 30% of GBS, the compressive strength of that developed to 574 kg/$\textrm{cm}^2$ at age of 28days and maximum temperature decreased to the extent of $5^{\cire}C$. When GBS and FA are mixed with concrete, it can be estimated that mix proportions of them have to be taken into consideration.

• Journal of Ceramic Processing Research
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• v.19 no.5
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• pp.378-382
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• 2018

It is a known fact that the cement production is responsible for almost 5% of total worldwide $CO_2$ emission, the primary factor affecting global warming. Geopolymers are valuable as ordinary Portland cement (OPC) substitutes because geopolymers release 80% less $CO_2$ than OPC and have mechanical properties sufficiently similar to those of OPC. Therefore, geopolymers have proven attractive to eco-friendly construction industries. Geopolymers can be fabricated from aluminum silicate materials with alkali activators such as fly ash, blast furnace slag, and so on. Integrated gasification combined cycle (IGCC) slag has been used for fabricating geopolymers. In general, IGCC slag geopolymers are fabricated with finely ground and sieved (<128 mesh) IGCC slag. The grinding process of as-received IGCC slag is one of the main costs in geopolymer production. Therefore, the idea of using as-received IGCC slag (before grinding the IGCC slag) as aggregates in the geopolymer matrix was introduced to reduce production cost as well as to enhance compressive strength. As-received IGCC slag (0, 10, 20, 30, 40 wt%) was added in the geopolymer mixing process and the mixtures were compared. The compressive strength of geopolymers with an addition of 10 wt% as-received IGCC slag increased by 19.84% compared to that with no additional as-received IGCC slag and reached up to 41.20 MPa. The enhancement of compressive strength is caused by as-received IGCC slag acting as aggregates in the geopolymer matrix like aggregates in concrete. The density of geopolymers slightly increased to $2.1-2.2g/cm^3$ with increasing slag addition. Therefore, it is concluded that a small addition of as-received IGCC slag into the geopolymer can increase compressive strength and decrease the total cost of the product. Moreover, the direct use of as-received IGCC slag may contribute to environment protection by reducing process time and $CO_2$ emission.

• Journal of the Korea Institute of Building Construction
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• v.10 no.6
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• pp.61-66
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• 2010

As global warming has had harmful effects on the environment, the construction industry has made efforts to reduce the amount of $CO_2$ generated in the process of cement production. There is an urgent need for an alternative material that can replace cement. To improve the initial strength and economical efficiency pointed out as problems, this research was conducted for Blast Furnace Slag (BFS), an industrial byproduct. Non-sintering cement (NSC) was used by minimizing the amount of high-priced alkali activators. By using Nano-technology, fineness has been maximized, to enhance the initial strength of BFS. This research is based on non-sintered cement replaced by nano-slag using alkali activators, and the fundamental properties and quality of the non-sintered cement were investigated. A variety of activators were used, up to 10 percent of the slag weight. This research aims to present fundamental data through a comparative analysis of flexural strength, compressive strength, time of setting, diabetic temperature, and rising heat.

• Journal of The Korean Society of Agricultural Engineers
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• v.64 no.4
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• pp.65-72
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• 2022

For sustainable development in the construction industry, blast furnace slag has been used as a substitute for cement in concrete. In contrast, ferronickel slag, which is the by-product generated during smelting to ferronickel used in the manufacturing of stainless steel and nickel alloys, has a limitation to use as a binder and an aggregate due to its expansive characteristics. Recently, stabilization technology of ferronickel slag has been improved and studies have been carried out to utilize ferronicke slag as fine aggregate in concrete. Therefore, in this study, basic mechanical properties of concrete used in ferronickel slag aggregate was evaluated. The compressive strength (24, 30, 40 MPa) and replacement rate of ferronickel slag aggregate (0, 10, 25, 50%) were considered as experimental variables. As a result of test, concrete replaced fine aggregate with 25% ferronickel slag aggregate showed superior performance in the compressive strength and flexural strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.409-414
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• 2001

The hydration of cement paste occurs when the cement is mixed with water. During the hydration, hydration heat causes the thermal stress depending on the size of concrete and the cement content. Especially in the high-strength concrete, we must give care to the concrete due to its large cement content. In this study, conduction calorimeter and concrete insulation hydration heat meter were used to investigate the hydration heat characteristics of cement and concrete. To reduce hydration heat of high-strength concrete, several types of replacement of fly-ash and blast-furnace slag powder were used in this experiment.