• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.605-608
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• 2008

콘크리트용 혼화재로 사용량이 날로 증대되고 있는 고로슬래그 미분말의 품질 차이가 콘크리트의 중성화에 어떠한 영향을 미치는지를 통계적으로 분석해 보았다. 현행 KS F 2563에 의하면 고로슬래그 미분말을 1종, 2종, 3종으로 구분하는데 3종에 해당하는 분말도 $4000cm^2/g$급 고로슬래그 미분말을 3곳으로부터 입수하여 Type A, B, C로 하여 다른 모든 조건은 동일하게 하고 혼입하였다. 본 연구에서는 기존의 그래프간의 단순비교를 통해 공학적 판단을 하는 오류를 배제하고자 평균값과 분산을 동시에 고려하는 통계적인 기법을 적용하였다. 분석기법에는 A, B, C 3개 집단간의 F검정과 각각의 쌍체비교를 위해 T검정 기법을 적용하여 통계적인 의미를 고찰해 보았다. 그 결과 유의수준 5%에서 중성화에 미치는 영향이 통계적으로 유의미한 것으로 나타났다.

• 전기학회논문지P
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• 제62권3호
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• pp.117-126
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• 2013

This paper is written for the development and application of boiler furnace pressure control algorithm and distributed control system of coal-fired power plant by the steps of design, coding, simulation test, site installation and site commissioning test. The control algorithms were designed in the shape of cascade control for two parts of furnace pressure control and induced draft fan pitch blade by standard function blocks. This control algorithms were coded to the control programs of distributed control systems. The simulator for coal-fired power plant was used in the test step and automatic control, sequence control and emergency stop tests were performed successfully like the tests of the actual power plant. The reliability was obtained enough to be installed at the actual power plant and all of distributed control systems had been installed at power plant and all signals were connected mutually. Tests for reliability and safety of plant operation were completed successfully and power plant is being operated commercially. It is expected that the project result will contribute to the safe operation of domestic new and retrofit power plants, the self-reliance of coal-fired power plant control technique and overseas business for power plant.

• 한국산업융합학회 논문집
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• 제26권6_2호
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• pp.1135-1144
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• 2023

In this paper, bending strength and permeability tests were conducted on concrete permeable blocks manufactured by recycling industrial by-products of oyster shell and blast furnace slag to measure and compare bending strength and permeability coefficient, and present experimental research results. To this end, a total of 54 specimens with a size of 200x200x60mm for surface layer and base layer were manufactured, and bending strength and permeability test were carried ourt accoridng to KS F 4419. Eighteen types of mixing designs were implemented by varying the mixing and replacement rates of oyster shells and blast furnace slag. As a result of the experiment, the higher the mixing ratio of oyster shell, the lower the bending strength and the permeability coefficient. Thereafter, a total of three permeable blocks with dimensions of 200x200x60mm were manufactured and subjected to bending strength and permeability tests according to KS F 4419. As a result of the test, the bending strength satisfies the standard of KS F 4419, and the permeability coefficient is 12 times higher than the standard of KS F 4419. It seems that the proper mixing of oyster shells and blast furnace slag increases the amount of air, and further research on durability and economic feasibility of materials used to manufacture permeable blocks is required.

• 한국지반신소재학회논문집
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• 제21권4호
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• pp.111-121
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• 2022

베트남에서 대량 발생하는 플라이애시는 누적 매립량이 약 1억톤에 이르고, 약 1억톤 정도이며, 고로슬래그 역시 약 585만톤 정도 발생하는 것으로 보고되고 있다. 이에 따라 최근 베트남에서도 플라이애시 및 고로슬래그를 재활용하기 위해 제도적으로 대응하고 있으나 아직 활발히 현장에 적용되지 못하고 있다. 이에 본 연구에서는 베트남 발생 플라이애시 5종에 대하여 기본 성능분석을 실시하였고, 베트남 발생 고로슬래그와 국내 발생 고로슬래그의 성능을 비교 평가하였다. 플라이애시와 고로슬래 그를 활용하여 지반안정재 압축강도시험, 지반혼합 고화토 일축압축강도 시험을 수행한 결과, 베트남 발생 플라이애시 및 고로슬래그를 지반안정재의 원료로 활용이 가능한 것을 확인하였다.

• 한국건설순환자원학회논문집
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• 제7권2호
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• pp.93-100
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• 2019

본 연구에서는 전기로 산화슬래그 잔골재를 30%, 50% 치환하여 초기재령 콘크리트의 역학적 특성을 평가하였다. 굳지 않은 콘크리트에서 슬럼프, 공기량, 단위용적질량을 검토하였으며, 경화 콘크리트에서 압축강도와 촉진 염화물 침투 실험을 진행하였다. 전기로 산화슬래그 잔골재 혼입량이 증가함에 따라, 슬럼프 및 공기량이 감소하였으며, 이는 전기로 산화슬래그의 다량의 미립분 및 거친 표면으로 인한 것으로 사료된다. 또한, 압축강도 발현율을 검토한 결과, 재령 7일까지 최대 111% 증가하였지만, 재령 28일에서 약 90%까지 감소하는 것을 확인할 수 있었다. 전기로 산화슬래그 혼입 콘크리트의 초기재령에서의 촉진 염화물 침투 실험결과 OPC 콘크리트와 큰 차이가 나타나지 않음에 따라 콘크리트 대체 골재로 사용함에 있어 충분한 성능을 갖고 있을 것으로 판단된다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.297-298
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• 2023

In the concrete industry, efforts are being made to reduce CO₂ emissions, and technologies that collect, store, and utilize CO₂ have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO₂ gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.761-766
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• 2002

This paper was peformed to verify the effect that granulated blast furnace slag gets in reinforcement corrosion resistance about chloride ion that invade from outside. An experiment accelerated for the reinforcement corrosion through repeat of brine digestion and dry. Reinforcement corrosion investigated half cell potential method of measurement by ASTM C876 and corrosion area ratio. If granulated blast furnace slag metathesis ratio is high generally that looked the corrosion of reinforcement decreasing as a result that evaluate reinforcement corrosion by ASTM C876 canon in this research. It showed high resistance about reinforcement corrosion that use normal portland cement and increase the metathesis rate of granulated blast furnace slag, as a result that evaluate metathesis rate effect of granulated blast furnace slag according to cement kind. when the test piece split destroying, area rate of reinforcement corrosion showed about result of half cell potential measurement.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 학회창립 10주년 기념 1999년도 가을 학술발표회 논문집
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• pp.95-98
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• 1999

Recently, the use of the underwater concrete constructions with the antiwashout underwater concrete is increasing. In this study, we investigate the properties of pH, suspended solids, slump flow, box test, air contents of fresh antiwashout underwater concrete and the Unit weight, compressive strength of hardened antiwashout underwater concrete which Ground Granulated Blast Furnace Slag contents 0%, 10%, 20%, 30%, 50%, 60% at 7days and 28days age which is produced and cured in the water and sea water. As a result, Ground Granulated Blast Furnace Slag contents 30% was excellent.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1996년도 춘계공동학술대회논문집; 공군사관학교, 청주; 26-27 Apr. 1996
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• pp.566-569
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• 1996

Steel making using EAF (Electric Arc Furnace) consists of three major processes: molten steel making, slab casting and hot rolling. Orders from customers, which includes their requirements such as composition, order quantity with allowable range, width, thichness, and unit weight of coils etc, are grouped as charges for EAF to enhance the productivity of the furnace. This paper develops an efficient grouping algorithm for charges in the EAF by exploiting the order characteristics: the allowable ranges of furnace capacity, order quantity, and unit weight of coils. Numerical test shows that the proposed heuristic works very efficiently and the results are quite satisfactory.

• 한국연소학회:학술대회논문집
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• 한국연소학회 1998년도 제17회 KOSCI SYMPOSIUM 논문집
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• pp.79-84
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• 1998

In this paper we show design and operation of 1MWth pulverized coal combustion test facility. The test facility is consists of coal feeding system, furnace and flue gas treatment system. The furnace is equipped with a top-fired burner in order to avoid influence of gravity on the coal particles. There are two part of vertical(VP) and horizontal pass(HP) at furnace. We can measure temperature and species of coal flames in vertical pass. Also, there is horizontally arranged section where investigation regarding corrosion and deposit formation will be carried out. The burner of combustor was externally air staging burner(EASB) type made by IFRF. The pulverized high bituminous(Blair athol) coal from Australia was used as fuel, and the particle size less than 80 ${\mu}m$ was 83.4%. Overall excess air ratio was 1.2.