Concrete, air and aggregates

The design of a good-quality concrete mix depends on a number of factors: the right balance between cement and water used, avoiding excessive air entrapment and the use of suitable aggregate.

Most Portland cement production is destined to become a part of concrete, whether ready-mix, precast, sprayed or other type. A typical mix for concrete is shown in Table 1.

Concrete contains three essential elements: aggregate (including coarse, fine and sand), cement and water. Most concrete will also contain some form of additive, whether a water reducer, air entrainer, accelerator or a retarder, or any combination of these.