ABSTRACT
This chapter describes some types of concrete that have been developed to extend the range of properties. These have been chosen to illustrate the tremendous versatility of concrete that has led to its use in an ever-increasing range of applications and structural situations. Some of these have been obtained by the use of alternative materials, such as lightweight and high-density aggregate concrete. Others have involved modifications to mix proportions, as in no-fines concrete, and the more extensive use of admixtures, as in sprayed concrete, high-strength concrete, flowing concrete, underwater concrete, self-compacting concrete (SCC) and foamed concrete. The chapter mentions aerated concrete, which is factory produced. Lightweight aggregates, which contain air voids within the aggregate particles, produce lower-density concretes than the normal-density aggregates. High-density aggregates can be used to produce high-density concrete for a number of specialised applications, such as radiation shielding, counterweights in construction plant (and even in domestic washing machines) and ballasting of submerged structures.
