건설 자재와 건설 폐기물의 환경적 영향에 대한 사회적 관심이 높아지고 있다. 고강도 콘크리트의 필요성이 점차 커짐에 따라, 본 연구에서는 서로 연관된 환경 문제에 대한 두 가지 잠재적 해결책을 검토하였다. 첫째는 재활용 콘크리트 골재의 사용량 증가 가능성이고, 둘째는 고로 슬래그를 시멘트로 활용(재활용)할 가능성이다. 일반적으로 재활용 골재를 사용하면 고강도 콘크리트의 강도 가 저하되는 것으로 알려져 왔다. 따라서, 본 연구에서는 재활용 골재 콘크리트의 배합비와 함량 변화를 분석하여 고층 건축에 재활용 골재가 실용적인지, 그리고 어떤 방식으로 활용되는지를 규명하고자 하였다.

Furnace slag powder used currently in Korea needs to add special functions in response to the increase of large-scale projects. In addition, it is advantageous in that it has a lower hydration heat emission rate than ordinary Portland cement and improves properies such as the inhibition of alkali aggregate reaction, watertightness, salt proofness, seawater resistance and chemical reslstance. However, furnace slag powder is not self-hardening, and requires activators such as alkali for hydration. Accordingly, if recycled fine aggregate, from which calcíum hydroxide is generated, and furnace slag, which requires alkali stimulation, are used together they play mutually complementary roles, so we expect to use the mixture as a resource-recycling construction material. Thus the present study purposed to examine the properties and characteristics of furnace slag powder and recycled aggregate, to manufacture recycled fine aggregate mortar using furnace slag and analyze its performance based on the results of an experiment, to provide materials on mortar using furnace slag as a cement additive and recycled fine aggregate as a substitute of aggregate, and ultimately to provide basic materials on the manufacturing of resource-recycled construction materials using binder and fine aggregate as recycled resources.

This study evaluates the material performance of slump value and compressive strength of the concrete which was made by recycled sand and blast furnace slag powder(BFSP). The main variables are replacement ratio of BFSP. As a result, it was evaluated that more detailed evaluation is needed in long-term strength development and the compensation of slump value to the replacement ratio of BFSP.

In this study, manufactured of cement mortar using high early strength cement(10 ~ 50 wt%) and blast furnace slag powder(50 ~ 90 wt%), according to compressive strength and flexural strength of hardened cement mortar. XRD and SEM were evaluated utilizing the initial cement hydration properties.