Effect Of Curing Conditions On Strength And Durability Of High-Performance Concrete

This paper describes the effects of variable curing temperatures on compressive strength and sulfate resistance of high-strength, high-performance concrete. Two different concrete mixtures were proportioned to attain the 56-day compressive strength of about 70 MPa upon moist-curing. One mixture contained more quantity of ASTM Class C fly ash than the other mixture. For each mixture, one set of specimens was cured in a standard moist-curing room at 23C and 100% relative humidity, and another set of specimens was sealed in plastic bags and cured in an elevated, variable-temperature curing environment (VTCE). The average temperature of the VTCE cycled between about 30C and 41C once per day. This study revealed that the VTCE-cured concrete did not exhibit significantly different compressive strength or ability to resist sulfates attack than the standard moist-cured specimens. Thus, based on the results of this research, it was concluded that additional effort to stabilize higher curing-temperatures would be necessary for field-cured concrete.