Chapter 19: Concrete mix design methods

The intention of concrete mix design is not only to choose suitably its ingredients, i.e. cement, aggregate, water and admixtures, but also to determine their relative proportions so as to produce concrete which is economical, strong, workable and durable. In routine and small-scale construction projects, concrete mixes may be chosen based on past experience, but when the use of different types of cementitious materials and different types of concretes are required for projects, especially to satisfy differing performance criteria (of both fresh and hardened concretes), more sophisticated techniques (including statistical approaches) may be needed to arrive at suitable mix proportions. The intention of this chapter is to demonstrate the different types of mix designs so that appropriate methods can be identified for different practical situations. However, it must be recognised that mix design is not an absolute science, but an art to satisfy a set of design criteria, by making use of the most appropriate materials for producing concretes which are economical.