• 한국건설순환자원학회논문집
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• 제7권4호
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• pp.302-309
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• 2019

본 논문은 5℃의 해수 환경에 노출한 알칼리 활성 플라이애시-슬래그 시멘트의 기본 특성에 관한 실험적 연구이다. 플라이애시와 슬래그의 배합비는 6:4, 7:3 및 8:2의 세 가지로 하였으며, 활성화제(수산화나트륨 및 규산나트륨)는 결합재 중량의 5%로 하였다. 실험 결과는 플라이애시의 치환율이 증가할수록 압축강도와 밀도는 감소하는 것으로 나타났으며, 또한 흡수율은 증가하는 것으로 나타났다. 경화된 샘플의 열중량 및 X선 회절분석을 통해 샘플 내에 생성된 반응물의 종류에는 변화가 없었으나, 슬래그의 치환율이 높을수록 C-S-H gel의 생성은 증가한 것을 알 수 있었다. 본 연구에서는 5℃의 해수에 노출된 알칼리 활성 플라이애시-슬래그 시멘트에서 플라이애시 보다 오히려 슬래그의 치환율이 샘플의 역학적 특성에 영향을 미치는 것으로 나타났다.

• 한국건축시공학회지
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• 제21권2호
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• pp.141-148
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• 2021

본 연구에서는 산업부산물 중 순환유동층 연소방식과 미분탄 연소과정에서 발생되는 플라이애시와 고로슬래그 미분말을 치환한 시멘트 모르타르의 특성을 파악하였다. 연구 결과, 순환유동층 플라이애시 및 미분탄 플라이애시 혼합 사용 시 강도발현 뿐만 아니라 내구성 측면에서도 유리하게 나타난다. 순환유동층 플라이애시는 초기 반응성 향상에 기여하며, 미분탄 플라이애시는 포졸란 반응으로 장기 강도 발현에 관여하게 된다. 따라서 순환유동층 플라이애시와 미분탄 플라이애시의 혼합사용은 고로슬래그 미분말을 치환한 시멘트 모르타르의 상호 보완적인 요소로 작용함을 알 수 있다.

• 한국도로학회논문집
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• 제9권4호
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• pp.93-104
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• 2007

본 연구는 포장재로서 투수콘크리트의 실질적인 현장적용을 위한 자료제시와 성능향상 방안을 도출하기 위하여 슬래그골재와 플라이애시의 혼입률에 따른 포장용 투수콘크리트의 역학적 특성을 평가하였다. 시험결과, 포장용 투수콘크리트의 공극률 및 투수계수는 슬래그골재의 혼합비율이 증가함에 따라 증가하고 플라이애시 혼입률 증가에 의하여 감소하는 경향을 나타내었으며 국내 포장용 투수콘크리트에 관한 규정(8% 및 0.01cm/sec)을 만족하였다. 압축강도 및 휨강도는 슬래그골재의 혼입률이 증가함에 따라 감소하였으나, 플라이애시의 혼입률이 증가함에 따라 크게 증가하는 경향을 나타내어 플라이애시를 5% 이상 혼입하면 슬래그골재를 50% 사용한 경우에도 국내 포장콘크리트에 관한 규정(18MPa 및 4.5MPa 이상)을 만족하였다. 또한 강섬유를 0.75vol.% 혼입한 경우 사용하지 않은 경우에 비하여 휨강도가 22.8% 증가 하였다. 미끄럼저항성은 슬래그골재의 혼입률이 증가에 따라 BPN값은 증가하였고, 플라이애시의 혼입률 증가에 의해 BPN값은 감소하는 경향을 나타내었으며, 내마모성 및 동결융해저항성은 부순골재만을 사용한 경우에 비해 슬래그골재의 혼합비율이 증가함에 따라 감소하였고, 플라이애시를 10% 혼입한 경우에는 현저히 개선되어 혼입하지 않은 경우에 비하여 내마모성 및 내동해성이 각각 약 5.6% 및 14.3% 정도 개선되는 것으로 확인되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
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• pp.231-236
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• 2000

In this study, to present the use of the blase furnace slag fly ash derived from a large amount of the industrial products with the early strength reduction of it prevented, the initial strength is measured after a large quantity of fly ash and the required stimulus agent for the high development of the initial strength was added in blast furnace slag cement. As the results, in spite of the much addition of fly ash in blast furnace slag, the long-age strength of blast furnace slag cement was able to be improved by a proper amount of stimulus agent, and was as high as that of ordinary portland cement.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.295-296
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• 2023

This study evaluated the compressive strength after making mortar with low cement composition for carbon-neutral steam curing to respond to climate change. Blast furnace slag, fly ash, and ultra-high powder fly ash were used as substitutes for cement. The cement substitute was used at 40% of the mass of cement, and after steam curing, the compressive strength was measured on the 1st, 3rd, 7th and 28th days of age. As a result of the experiment, at the age of 1 day, the mixture using only cement showed the highest strength, but from the 3rd day, the specimen using ultra-high powder showed a high strength development rate, followed by blast furnace slag and fly ash.

• 한국건축시공학회지
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• 제2권2호
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• pp.145-150
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• 2002

The hydration of cement paste occurs when the cement is miked with water. During the hydration, hydration heat causes the thermal stress depending on the site 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 investigation 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. As a result of this study, it was found that hydration heat of high-strength concrete was reduced by replacement of fly-ash and blast-furnace slag powder. In case of high-strength concrete using blast-furnace slag powder, the max-heat arrival time was delayed but an effect of heat reduction was lower than a case of high-strength concrete using fly-ash, because it was considered that the heat-dependence property of blast-furnace slag powder was higher than that of fly-ash.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2011년도 추계 학술논문 발표대회
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• pp.31-32
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• 2011

Granulated slag from metal industries and fly ash from the combustion of coal are industrial by-products that have been widely used as mineral admixtures in normal and high strength concrete. Due to the reaction between calcium hydroxide and fly ash or slag, the hydration of concrete containing fly ash or slag is much more complex compared with that of Portland cement. In this paper, the production of calcium hydroxide in cement hydration and its consumption in the reaction of mineral admixtures is considered in order to develop a numerical model that simulates the hydration of concrete containing fly ash or slag. The heat evolution rates of fly ash- or slag-blended concrete is determined by the contribution of both cement hydration and the reaction of the mineral admixtures. Furthermore, the temperature distribution and temperature history in hardening blended concrete are evaluated based on the degree of hydration of the cement and the mineral admixtures. The proposed model is verified through experimental data on concrete with different water-to-cement ratios and mineral admixture substitution ratios.

• Computers and Concrete
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• 제4권6호
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• pp.425-436
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• 2007

This study is mainly focused on applying Fuller's ideal gradation curve to theoretically design blended ratio of all solid materials of a reactive powder mortar (RPM), also known as reactive powder concrete (RPC), with the aid of error function, and then to study the effect of fly ash/slag on the performance of RPM. The solid particle is assumed to be spherical particles. Then, the void volume of paste ($V_{\nu}$) and the paste content with specific quality can be obtained. As conclusion, under Fuller's ideal grading curve, the amount of fly ash/slag mixture is higher than that with silica fume along due to it better filled the void within solid particle and obtains higher packing density.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.204-205
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• 2018

This paper investigates CO₂ emission and cost analysis of blended concrete which was added with fly ash and slag. Three kinds of blended concrete were studied in this investigation, the first blended concrete was added fly ash replacing part of the cement while the second was added slag, the third was added fly ash and slag. Analysis result display that the blended concrete containing fly ash and slag is the optimal choice while considering economic and CO₂ emissions.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.272-277
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• 2000

This study is performed to evaluate the engineering properties of permeable polymer concrete with blast furnace slag and fly ash. The following conclusions are drawn; 1. The highest strength is achieved by 50% filled blast furnace slag powder and fly ash permeable polymer concrete, it is increased 36% by compressive strength, 119% by tensile strength and 217% by bending strength than that of the normal cement concrete, respectively. 2. The ultrasonic pulse velocity is in the range of 2,022 ∼ 2,139m/s. The highest pulse velocity is showed by 50% filled blast furnace slag powder and fly ash permeable polymer concrete. 3. The water permeability is in the range of 4.612∼5.913$\ell$/$\textrm{cm}^2$/h, and it is largely dependent upon the mix design.