ABSTRACT
A significant and steadily increasing proportion of concrete used in construction has been substantially modified to produce mixes with properties both in their fresh and/or hardened states much different from those of the ordinary ones. The traditional cement-water-aggregate mix-design was altered and new ingredients, either singly or in combinations were introduced into the mix. The modifications were designed to improve the quality of the concrete which in most circumstances meant making concrete perform better in more demanding conditions of service and become more suitable for handling by specialised methods of construction.
