Shrinkage-Compensating Concrete: An Investigative Study

As wet concrete cures, loss of moisture causes the concrete to contract. This contraction of the concrete, referred to as drying shrinkage, can create stresses than may cause the concrete to crack. Components can be added to concrete mixes to produce controlled, expansive chemical reactions that reduce or eliminate this drying shrinkage—in effect producing a shrinkage-compensating concrete. This paper provides a general overview of shrinkage-compensating concrete (SCC) including factors that influence the final concrete product and parameters for construction. A comparison of properties between SCC and regular portland cement concrete has been developed and is presented for SCC formed both with expansive cement and an expansive component. Early deterioration of concrete caused by delayed ettringite formation (DEF), which can occur with the use of expansive cement, is investigated, as well as alleviation of DEF by use of an expansive component.