구조체 콘크리트와 온도 추종 양생 실린더 콘크리트 공시체의 적산온도 및 강도 비교 평가에 대한 실험적 연구

초록

Recently, quality deterioration in concrete used for reinforced concrete (R/C) structures has become a growing concern in domestic construction practice. These issues are mainly attributed to variations in raw material quality and temperature conditions during placement and curing. In particular, temperature variations during curing can significantly influence the hydration process, leading to insufficient strength development and potential reductions in structural safety. This study was conducted as a fundamental investigation to address temperature-related quality problems by utilizing the hydration heat of structural concrete. The hydration heat history of structural members was predicted and reproduced at the laboratory scale to perform temperature-following curing of concrete cylinders. The experiment aimed to verify whether the mix design used in field placement could achieve the target design strength at 28 days. As a result, the temperature-following cured specimens maintained a maximum hydration temperature difference of less than 1 °C and showed less than a 2 % deviation in cumulative temperature compared to actual insitu measurements. The compressive strength at 28 days differed by approximately 9.3 % from that of field concrete, and the correlation coefficient (R2) between the predicted and measured strengths reached 0.9629, indicating excellent agreement. These findings demonstrate that temperaturefollowing curing based on predicted hydration heat can effectively reproduce field temperature histories and accurately estimate in-situ strength development. Consequently, the proposed approach provides a practical foundation for improving strength prediction and quality control in cast-in-place concrete for R/C structures.

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