- 시멘트 배합량이 콘크리트의 소성수축에 미치는 영향
- The Effect of Cement Mixture on Plastic Shrinkage of Concrete
- ㆍ 저자명
- 오무영,윤충섭
- ㆍ 간행물명
- 한국농공학회지
- ㆍ 권/호정보
- 1976년|18권 4호|pp.4226-4231 (6 pages)
- ㆍ 발행정보
- 한국농공학회
- ㆍ 파일정보
- 정기간행물| PDF텍스트
- ㆍ 주제분야
- 기타
The objective of this study is to investigate the characteristics of the concrete mixture and the plastic shrinkage of concrete exposed to a rapid evaporation immediately after placement, and to measure the shringkage rate according to the cement-mixture. Drying of concrete was conducted under a controlled chamber in which the temperature was 36${pm}$2$^{circ}C$, the relative humidity 45${pm}$2%, and the wind velocity 4${pm}$1m/sec. All of the concrete mo1ds were made to have good workability as 6${pm}$0.5cm in slump. The results obtained are as follows; 1) The evaporation rate was 3.36kg/$ extrm{km}^2$, 2.98kg/$ extrm{km}^2$ and 2.91kg/$ extrm{km}^2$ respectively for each concretemixtures 365kg, 335kg and 317kg after 5 hour exposure, and the evaporation was measured at all 55∼57% after 2 hours and additional in 10% on after 5 hours exposure. 2) The weight of the concrete were was reduced to 3.0%, 2.6% and 2.4% respectively for each of them. 3) The shrinkage of concrete was 0.87 mm/m, 0.56mm/m and 0.31 mm/m after 5 hour exposure, and the shringkage of concrete was measured at 84%, 59% and 45% after 2 hours and it in 1∼5% after 5 hour exposure and then stopped. 4) A recommendation for good concrete is that the evaporation should be minimized during 2 hours after placement of concrete, if possible.