Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Characteristics of Chloride Diffusion and Compressive Strength in the Mortar containing C12A7 based Binder and Anhydrite

C12A7계 바인더와 무수석고를 혼입한 모르타르의 염화물 확산 및 압축강도 특성

  • Byeong-Cheol, Lho (Department of Civil Engineering, Sangji University) ;
  • Yong-Sik, Yoon (Department of Civil and Environmental Engineering, Hannam University)
  • 노병철 (상지대학교 건설시스템공학과 ) ;
  • 윤용식 (한남대학교 토목환경공학과)
  • Received : 2022.11.10
  • Accepted : 2022.12.02
  • Published : 2022.12.30
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Abstract

In this study, as the preliminary research on the development of heating concrete members, compressive strength and accelerated chloride diffusion behavior in the mortar specimens containing C12A7 based binder and anhydrite was evaluated. Also, the effect of the mixing ratio of the citric acid based retarder was quantitatively evaluated by considering 4 levels of mixing cases. The compressive strength tests of the mortar specimen were performed referred to KS L ISO 679, and the accelerated chloride diffusion tests were performed according to NT BUILD 492 and ASTM C 1202. In the mortar with 0.3 % of retarder, the highest compressive strength was evaluated, which showed the strength development ratio of 127.6 % compared to the control case. It was considered that engineering performance was improved by effectively securing setting and curing time with 0.3 % of citric acid based retarder. As the result of the evaluation of the passed charge and the accelerated chloride diffusion coefficient, the evaluation results had similar behavior with the results of compressive strength. According to the previous study, the strength behavior and the chloride diffusion behavior had a linear relationship. The mixture showing the highest strength performance had the highest durability performance for chloride ingress, and the heating concrete development from this study will be performed in the future.

본 연구에서는 발열 콘크리트 부재 개발의 사전 연구로써 C12A7계 바인더와 무수석고를 혼입한 모르타르 시편의 압축강도 및 촉진 염화물 확산 거동을 분석하였다. 또한, 무수구연산계 지연제의 혼입률 4수준을 고려하여 지연제 혼입률이 미치는 영향을 정량적으로 평가하였다. 모르타르 시편의 압축강도는 KS L ISO 679, 촉진 염화물 확산 시험은 NT BUILD 492 및 ASTM C 1202에 준하여 수행하였다. 무수구연산 지연제 혼입률이 0.3 %인 경우에서 가장 높은 강도가 평가되었으며 이는 컨트롤 케이스 대비 127.6 %의 강도 증진률을 나타내었다. 무수구연산 지연제 혼입률 0.3 %에서 효과적으로 가사시간 및 경화 시간을 확보하여 성능이 개선된 것으로 사료된다. 통과 전하량 및 촉진 염화물 확산계수 평가 결과 압축강도와 비슷한 성능 평가 결과가 도출되었으며, 기존의 연구에 따르면 강도 거동과 염화물 확산 거동은 선형적 관계를 갖기 때문이다. 가장 높은 강도 성능을 나타낸 배합에서 가장 높은 염해 저항성을 나타내었으며, 본 연구 결과를 기반으로 추후 발열 콘크리트 부재 개발을 수행할 계획이다.

Keywords

Acknowledgement

본 연구는 국토교통부/국토교통과학기술진흥원의 지원으로 수행되었음(과제번호22RITD-C162337-02).

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