Journal of the Korea Institute of Building Construction (한국건축시공학회지)

The Korean Institute of Building Construction (한국건축시공학회)
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Fundamental Characteristics of CO2-cured Mortar with Varied Rates of Blast Furnace Slag Fine Powder Substitution

고로슬래그 미분말 치환율에 따른 이산화탄소 양생 모르타르의 기초 물성

  • Received : 2023.10.26
  • Accepted : 2023.12.27
  • Published : 2024.02.20
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Abstract

This research elucidates the fundamental properties of carbon dioxide (CO2)-cured mortar as influenced by varying substitution rates of blast furnace slag fine powder. The findings indicate that CO2 curing enhances the formation of calcium carbonate (CaCO3), contributing to pore reduction and the early development of strength. While calcium hydroxide (Ca(OH)2) plays a more pivotal role in the primary development of strength compared to CaCO3, an increase in the substitution rate of blast furnace slag fine powder results in reduced production of Ca(OH)2. Nonetheless, the maintenance of strength through CaCO3 formation is observed even after the depletion of Ca(OH)2, suggesting that the required performance can be sustained post-exposure to the atmosphere following CO2 curing. It is noted that substitution rates exceeding 50% lead to performance deterioration due to CO2, highlighting the necessity for careful adjustment of the substitution ratio.

본 실험에서는 고로슬래그 미분말 치환율에 따른 이산화탄소 양생 모르타르의 기초 물성을 확인하였다. 실험 결과, 이산화탄소 양생은 CaCO3의 생성을 촉진하며 공극 감소와 조기 강도 발현에 영향을 준다. Ca(OH)2가 CaCO3보다 주된 강도 발현에 영향을 주며 고로슬래그 미분말 치환율이 높은 배합일수록 Ca(OH)2 생성이 감소한다. 하지만 Ca(OH)2가 소모된 이후에도 CaCO3를 통해 강도가 유지되며 이산화탄소 양생 이후 대기 중에 노출하여도 소요의 성능을 유지할 수 있을 것으로 전망된다. 고로슬래그 미분말 치환율이 50%를 초과할 경우 이산화탄소에 의한 성능 저하를 유발하므로 치환 비율을 조정할 필요가 있다.

Keywords

Acknowledgement

This research was supported by the Korea Research Foundation with the funding of the government(Ministry of Science and ICT)(2023R1A2C2003956).

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