• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
• /
• pp.85-88
• /
• 2006

This study investigated influence of fine aggregate types on fundamental properties of cement mortar. Test showed that concrete using lime stone crushed fine aggregate(L) exhibited the most favorable fluidity due to grain shape and particle distribution, and next was blending aggregate miting L and G, blending aggregate mixing L and N, granite crushed fine aggregate(G), natural fine aggregate(N) in an order. Concrete using N had the highest air content and L was the smallest value because of the effective filling performance by continuos particle distribution. Compressive, tensile and flexural strength of all concrete using L had the highest value due to the smallest value of air content. It is also found that concrete using L resulted in decrease of drying shrinkage length change ratio.

• 대한건축학회논문집:구조계
• /
• 제36권1호
• /
• pp.155-162
• /
• 2020

The aim of the research is to investigate the fundamental properties and heat of hydration reducing performance of the fly ash incorporated concrete mixture when the coal gas slag (CGS) from integrated gasification combined cycle (IGCC) is used as fine aggregate. From the results of the experiment, the workability was generally increased and the air content was decreased up to one to four percent with increasing the replacing ratio of CGS to fine aggregate. The compressive strength was similar or increased within five percent to the Plain mixture when the CGS was used as a fine aggregate. When the CGS and fly ash were used same time, the heat of hydration reducing performance was improved than single using cases either CGS or fly ash. Based on the results, for the concrete mixture using CSG as a portion of the combined fine aggregate, the general properties were improved and heat of hydration was decreased approximately 16 % when the fly ash was replaced 30 % to cement and the CGS was replaced less than 50 % to fine aggregate.

• 한국건설순환자원학회논문집
• /
• 제3권2호
• /
• pp.171-179
• /
• 2015

최근 건설산업에서는 천연 골재 고갈과 엄격한 환경 규제로 인하여 골재 부족 현상이 지속되고 있기 때문에 대체 골재 개발이 시급한 실정이다. 따라서 본 연구에서는 기존 전로슬래그 처리방식의 문제점을 해결하기 위한 새로운 처리방식 즉, 고온 용융슬래그를 회전식 드럼내에 투입한 다음 냉각수, 압축공기 및 강철구를 이용하여 급속 냉각, 파쇄 처리하는 공정에서 발생되는 습식 급랭 전로슬래그를 콘크리트용 잔골재로 활용하기 위하여 기초물성을 검토하였다. 또한 본 연구를 통하여 콘크리트용 잔골재로써 습식 급랭 전로슬래그의 활용 방안을 제안하고자 한다.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2014년도 추계 학술논문 발표대회
• /
• pp.55-56
• /
• 2014

In this research, the effect of types of aggregate and SP on fundamental properties of ultra-high performance concrete of 80 MPa of compressive strength was evaluated to provide solution for high cost of ultra-high performance concrete. As the results of a series of tests, the mixture using limestone and silica aggregates showed improved workability rather than the mixture using granite aggregate. For compressive strength of UHPC, the UHPC mixtures using limestone and silica aggregates showed higher compressive strength than the UHPC mixture using granite aggregate while all mixtures satisfied target compressive range.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1996년도 봄 학술발표회 논문집
• /
• pp.18-23
• /
• 1996

Since at least three-quarters of the volume of concrete is occupied by aggregate, it is not surprising that its quality is considerable importance. Not only may the aggregate limit the strength of concrete, as weak aggregate cannot porduce strong concrete, but the properties of aggregate greatly affect the durability and sructural performance of concrete. But, it is ture that aggregate strength is usually not a factor in normal concrete strength because the aggregate particle is several times stronger than the matrix and the transition zone in concrete. This study is to consider the influence the strength of concrete according to the kinds of aggregate, such as crushed river rocks, curshed rocks, high strength recycled aggregate, low strength recycled aggregate at water cement ratio 0.25. It is possible to concern the important of the mechanical role of aggegate for the high strength concrete.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(II)
• /
• pp.105-108
• /
• 2005

This study investigated fundamental properties of the recycled aggregate which was produced through recent hi-techniques of recycling. In addition, the mechanical properties of the concrete that used the recycled aggregate were compared to the concrete used the natural aggregate. From the results of the mechanical property tests, as the recycled aggregate replacement ratio increased, the compressive strength and elastic modulus decreased. When the recycled aggregate completely replaced the natural aggregate, the compressive strength and elastic modulus was about 15$\%$ and 35$\%$ lower than the natural aggregate concrete, respectively. Based on the test results, equations for prediction of compressive strength and elastic modulus were suggested in the consideration of the amount of the replaced recycled aggregate. Based on the test results and study, the equation predicting the required development length of the recycled aggregate concrete is proposed.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
• /
• pp.178-179
• /
• 2017

In this study, the fundamental properties of cement mortar in relation to the change of the replacement ratio of the RA(Reject-Ash) were analyzed by mixing RA to the mixed aggregate consisting of poorly graded fine rock aggregate and marine aggregate for quality improvement. It was found that replacing 5% of the mixed aggregate with RA could improve the quality of the aggregate to the degree of fine rock aggregates.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
• /
• pp.57-60
• /
• 1993

To analyze the using of recycled aggregate on concrete as the substitude aggregate is important problem for the reuse of waste matter and prevention of environmental pollution. Therefore, this study is designed for investigation and analyzing the mechanical properties and early estimational factors of strength on concrete sing aggregate of the waste concrete. And is aimed to provide the fundamental data for recycled aggregate.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1996년도 가을 학술발표회 논문집
• /
• pp.253-259
• /
• 1996

The purpose of this study is to investigate the fundamental properties of polyurethan concrete. Polyurethane must be expanded by means of a blowing agent during polymerization. Chemical blowing is caused by the reaction water with isocyanate. Binder system for polyurethane concrete is based on polyol and isocyanate with catalyst, surfactant, and methyl chloride. Polyurethane concretes are prepared with various grading of aggregate, and tested for compressive, flexural strengths, flow test, foaming multiple proportion, working life, condition of surface, distirbution of aggregate. From the test results, the foaming of polyurethane concretes are affceted by amount and grading of aggregate. Workability increases with raising amount of methy chloride and working life reduced according to amount of catalyst. The mix proportion of B with methyl chloride of 1% and catalyst of 0.1g for polyurethane concrete is recommended in consideration of strengths, condition of surface and balance between cost and performance.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 2000년도 봄 학술발표회 논문집
• /
• pp.275-278
• /
• 2000

In this paper, we carried out fundamental experiments to use steel manufacturing slag as a concrete aggregate. Generally, there are two types of slag, the blast-furnace slag and the steel manufacturing slag. The latter is classified by the difference of manufacturing method of steel into the convertor slag and the electric-furnace slag. The steel manufacturing slag mainly contains $SiO_2$ and CaO as the chemical composition. The reaction with water and a little of free CaO in the steel manufacturing slag made the expansion of volume change, Therefore, we primarily investigated physical properties, expansion mechanism, pH value, aging effect and aging methods in the steel manufacturing slag, Then compressive strength of concrete with steel slag aggregate is measured.