| Summary: In this study, the effect of steam curing on the freeze-thaw resistance of SCC produced with fly ash was investigated. To accomplish this, three series of SCCs with a total amount of binder of 500 kg/m3, 550 kg/m3, and 600 kg/m3 were produced. In each series, fly ash is substituted with cement at ratios of 0%, 20%, 30%, 40% and 50% by weight of the binder. Six of the specimens were used for steam curing. One of the specimens of steam cured is subjected to F-T for 100 cycles. The rest of the specimens were kept in standard curing condition for 27 days. At the end of 28 days of standard curing, one specimen of steam cured and one specimen of standard cured are subjected to F-T. Per 25 F-T cycles, the ultra velocities of the specimens subjected to F-T for 100 cycles were measured to monitor the mass loss and the interior damage of the specimens. At the end of F-T cycles, the compressive strength of the specimens, along with those of standard cured was determined. The steam cured SCCs at the end of one day have gained a strength of 40-60% of the 28 day of compressive strength. However, the 28 day compressive strength of steam cured specimens has been decreased compared to those of standard cured ones. As the fly ash content increased, the damage due to steam curing is decreased. At the end of 100 cycles of F-T the steam cured specimens, the least strength loss was observed in those with a fly ash substation ratio of 40%. No significant mass loss and ultra velocity variation have been observed for all concretes.
Key Words: Self Compacting Concrete, Fly ash, Steam curing, Freezing-Thawing
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