PURPOSES: In this study, we analyzed the compressive strength characteristics of lean base concrete in relation to changes in the outdoor temperature after analyzing the cold and hot weather temperature standards and calculated the minimum and maximum temperatures when pouring concrete. We examined the rate of strength development of lean base concrete in relation to the temperature change and derived an appropriate analysis formula for FRC base structures by assigning the accumulated strength data and existing maturity formula. METHODS: We measured the strength changes at three curing temperatures (5, 20, and 35℃) by curing the concrete in a temperature range that covered the lowest temperature of the cold period, 5℃, to the highest temperature of the hot period, 35℃. We assigned the general lean concrete and FRC as test variables. A strength test was planned to measure the strength after 3, 5, 7, 14, and 28 days. RESULTS : According to the results of compressive strength tests of plain concrete and FRC in relation to curing temperature, the plain concrete had a compressive strength greater than 5 MPa at all curing temperatures on day 5 and satisfied the lean concrete standard. In the case of FRC, because the initial strength was substantially reduced as a result of a 30% substitution of fly ash, it did not satisfy the strength standard of 5 MPa when it was cured at 5℃ on day 7. In addition, because the fly ash in the FRC caused a Pozzolanic reaction with the progress into late age, the amount of strength development increased. In the case of a curing temperature of 20℃, the FRC strength was about 66% on day 3 compared with the plain concrete, but it is increased to about 77% on day 28. In the case of a curing temperature of 35℃, the FRC strength development rate was about 63% on day 3 compared with the plain concrete, but it increased to about 88% on day 28. CONCLUSIONS: We derived a strength analysis formula using the maturity temperatures with all the strength data and presented the point in time when it reached the base concrete standard, which was 5 MPa for each air temperature. We believe that our findings could be utilized as a reference in the construction of base concrete for a site during a cold or hot weather period.

1. 서론
2. 외기온도에 따른 콘크리트의 시공구분
3. 한랭기 및 서중 콘크리트의 강도발현 성능 검토
4. 적산온도에 의한 FRC 기층 강도발현 성능 분석
5. 기층 기준 강도 5MPa 도달시기 예측
6. 결론
감사의 글
REFERENCES

• 최성용((주)이노블록 기술연구소 선임연구원) | Choi, Sung-Yong 주저자
• 박영환(한국건설기술연구원 구조융합연구소 선임연구위원) | Park, Young-Hwan
• 정우태(한국건설기술연구원 구조융합연구소 수석연구원) | Jung, Woo-Tai 교신저자