Title: Performance of High Alumina Cement Concrete Stored in Water and Dry Heat at 25, 35, and 50 C
Author(s): D. H. H. Quon and V. M. Malhotra
Publication: Journal Proceedings
Appears on pages(s): 180-183
Keywords: age-strength relation; compression tests; compressive strength; concretes;
curing; differential thermal analysis; high alumina cements; moist curing;
water-cement ratio; x-ray diffraction.
Continuing work undertaken in 1975 at CANMET a series of 0.056 m3 concrete mixes was made, and 30 cylinders cast from each mix. After initial moist curing, one-third were subject to standard moist curing, one-third cured in water, and one-third in dry heat. A similar procedure was repeated at higher temperatures. Weights and pulse velocity of the cylinders were determined, and they were examined by x-ray diffraction and differential thermal analysis. High alumina cement concretes moist cured at 21 C gain in strength up to one year, regardless of water-cement ratio. But curing at 25 and 35 C results in strength loss with age, and this loss increases with increasing water-cement ratio. At 50 C exposure, the change in strength with age depends on the water-cement ratio. At a water-cement ratio of 0.31, an insignificant drop in strength occurs at early ages, despite the high degree of conversion. Strength then increases with age and reaches 125 percent of one-day strength at one-year, suggesting a means by which very high strengths can be achieved and maintained at least up to one year.