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What are set-controlling admixtures?

Q. What are set-controlling admixtures?


A. Set-controlling admixtures are used to modify the time of setting (ACI 212.3R). Retarding admixtures extend the time of setting. They are used in hot weather to compensate for the effects of high temperature. Accelerating admixtures reduce the time of setting and accelerate early strength development. They are used in cold weather to compensate for the effects of low temperature.


References: SP-1(02); ACI CT-23; E4-12; ACI 212.3R-16; SP-288; ASTM C494

Topics in Concrete: Admixture; Concrete Fundamentals; Cold Weather; Materials; Hot Weather

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