A. It is an admixture that causes the event of the method of microscopic air bubbles in cement paste during mixing, typically to boost its resistance to freezing and thawing and to further improve workability (ACI 212.3R). What Is Concrete Retarder? Concrete retarder is often a type of admixture or https://air-entraining30640.thezenweb.com/air-entraining-admixture-fundamentals-explained-70346834