고로슬래그 미분말의 치환율과 분말도가 시멘트 모르타르의 자기수축에 미치는 영향

초록

This study experimentally analyzed the effects of replacement ratio and fineness of ground granulated blast-furnace slag (GGBFS) on the autogenous shrinkage of cement mortar. The specimens were fabricated with GGBFS content (0, 50, 65 and 80 % by weight of binder) and fineness (4,330, 7,650 cm2/g) as variables, and the internal relative humidity and autogenous shrinkage were measured. The self-desiccation and autogenous shrinkage of the specimens with GGBFS replacement ratio up to 65 % increased as the content of the GGBFS increased whereas those decreased in the specimens with the GGBFS replacement ratio of 80 %. This is because GGBFS changed the pore structures and hydration of cementitious materials, resulting in the changes in the radius of meniscus formed inside the pores and eventually changes in the capillary stresses. In addition, the self-desiccation and autogenous shrinkage of cement mortar increased with increasing fineness of GGBFS. © 2020 by Korea Concrete Institute.

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