ABSTRACT
Concrete is no longer a rationalized mixture of cement, sand and stone, but has matured to an engineered material containing a mixture of admixtures. Admixtures modify the structure-property relationship of normal concrete by chemically altering the rate of cement hydration and or, the nature of the hydration products. The last decade has seen a wide interest in many aspects of admixtures and research on the chemistry of the aqueous phase of the cementwater-admixture system has demonstrated that admixtures can control the type of products formed so that many properties can be designed into concrete. The correct combination of admixtures can produce concrete that is custom-made for the particular job at hand.
