ABSTRACT
Concrete — There has been a continuous increase in the strength of concrete over the last hundred years; much of the increase has developed since 1980 (see Figure 7.1). Around that time, the value of blended cements and the use of admixtures was realised. Modern concretes have become complex with almost in‡nite variations available depending on the requirements. The understanding of how to change the properties of concrete and reinforcement is developing rapidly. It includes:
• The use of admixtures and blended cements. Admixtures are essential for modern concrete. Self-compacting concrete is one important example. Blended cements allow the control of the rate of strength gain and the amount of heat created.
