PURPOSES : The purpose of this study was to investigate the performance of additives that affect internal curing in order to reduce the damage occurring in concrete pavements.
METHODS : SAP was used as an additive to reduce internal curing in concrete pavements. SAP is an additive that has a very high absorption rate which prevents concrete wrappers from externally draining water. To evaluate the internal curing performance according to the ratio of SAP, we identified the number of cracks and amount of abrasion reduction.
RESULTS : Plastic shrinkage and durability of a concrete mixture with added SAP were evaluated. The following results were obtained: (1) SAP showed a tendency to reduce slumps due to absorption of the concrete mixture. (2) It was possible to verify that concrete condensation did not occur during the penetration resistance test and that the initial curing did not lead to reactions within the mixture. (3) Adding more than 0.6% of SAP for dry curing resulted in greater compressive strength at all ages than OPC, with the highest compression strength of 0.9% after 56 days. (4) Regarding abrasion resistance, it was found that adding SAP was 30~50% better than adding the OPC mixture, and at 0.9% compression strength, abrasion resistance showed the best performance. (5) In the chlorine ion immersion resistance experiment, the passing charge of the OPC mixture was rated “high,” but it was rated “normal” in SAP. The results showed that the addition of SAP improved the water density of concrete due to internal curing effects, and that it showed the greatest chlorine ion penetration resistance for a compressive strength of 0.9%. (6) Regarding plastic shrinkage resistance, cracks did not occur on the surface until the end of the experiment, but the plastic shrinkage rate upon addition of SAP was relatively low compared to that of the OPC mixture.
CONCLUSIONS : Recent studies have shown that internal curing techniques can be applied using SAP to prevent shrinkage due to the loss of water and to decrease the effects of hydration. If internal curing effects are expressed using SAP, it is thought that contraction due to a loss of moisture and reduction in sign language reaction can be prevented.

ABSTRACT
1. 서론
2. 실험계획
    2.1. 개요
    2.2. 사용재료
    2.3. 콘크리트 배합비
    2.4. 실험방법
3. 실험결과 및 분석
    3.1. 슬럼프 및 공기량 측정결과
    3.2. 관입저항실험 결과
    3.3. 압축강도 측정결과
    3.4. 마모저항성 측정결과
    3.5. 염소이온침투저항성실험 측정결과
    3.6. 소성수축균열실험 측정결과
4. 결론
REFERENCES

• 노재면(한국건설기술연구원 인프라안전연구본부) | Roh Jae Myun
• 전성일(한국건설기술연구원 노후인프라센터) | Jeon Sung IL 교신저자
• 정진훈(인하대학교 토목공학과) | Jeong Jin Hoon