William S. Phelan is Senior Vice President of Marketing and Technical Services for the Euclid Chemical Company. He is an Honorary Member and Fellow of ACI. ACI 212.3R-10, Report on Chemical Admixtures for Concrete, was chaired by Mr. Phelan. (euclidchem@att.net)
Admixtures are used to modify and improve the properties of fresh and hardened concrete. The use of the proper admixtures can result in increased workability, cementitious efficiency (psi per pound of cement), and optimum setting time with mixes, even those with low water/cementitious ratios. …
Self-consolidating concrete (SCC) is increasingly used for reinforced formed-members, architectural concrete, and floors and slabs. It is often the only solution for structural repairs. SCC is a highly flowable, non-segregating concrete with a slump/flow of 20 to 30 inches. SCC can be easily placed and completely fills forms under its own weight without mechanical vibratory consolidation. …