PURPOSES : Experimental findings pertaining to the mechanical properties and microstructures of calcium sulfo-aluminate (CSA) cement and amorphous calcium aluminate (ACA) cement based-repair mortars incorporated with anhydrite gypsum (AG) are described herein. METHODS : To prepare the mortars, the CSA or ACA as binders were adopted and the ratio of water–binder was fixed at 0.57. For comparison, mortar made of Type I ordinary Portland cement (OPC) was prepared. The fluidity, setting time, compressive and bond strengths and absorption of the mortars were measured at predetermined periods. In addition, the microstructures of paste samples using OPC, CSA or ACA were visually examined through SEM observation. RESULTS : The ACA-based mortars showed the increases in the fluidity, and the acceleration of the setting time. Furthermore, the ACAbased binder effectively enhanced the compressive and bond strengths of the mortars owing to amount of formation of C2AH8 hydrates. Meanwhile, the mortar with ACA showed an excellence absorption. CONCLUSIONS : Comparing with those of CSA-based mortars, the mechanical properties of ACA based-mortars were more remarkable. However, further studies regarding the durability of repair mortars using aluminate-based binders must be conducted to obtain the optimal mixture.

1. 연구배경 및 목적
2. 실험개요
    2.1. 사용재료
    2.2. 배합
    2.3. 실험방법
3. 실험결과 및 고찰
    3.1. 플로우
    3.2. 응결특성
    3.3. 강도특성
    3.4. 흡수율
    3.5. 미세구조
4. 결론 및 요약
감사의 글

• 이승태(정회원 · 군산대학교 토목공학과 교수) | Lee Seung-Tae (Associate Professor Department of Civil Engineering, Kunsan National University, 558 Daehak-ro, Kunsan, Jeonbuk 54150, Korea) 교신저자