It may be defined as the concrete of substantially lower unit weight than that made from gravel or crushed stone.
Ordinary concrete is quite heavy and its density is 2300 kg/m3. It is not suitable for use in floor filling as filler in general. If used, it adds considerably to the dead weight of the structure. By using suitable aggregates the density of concrete can be reduced. This light weight concrete not only results in reducing dead weights on structure, but also has a better insulation against heat and sound. The strength of such concrete is however low. But it is of no consequence as this concrete is not expected to bear any loads. Because of the light weight, this concrete is very suitable for earthquake proof structures.
Application of Lightweight Concrete
Light weight concrete finds its use generally in situations like:
Decks of long span bridges.
Fire and corrosion protection.
Covering for architectural purposes.
Heat insulation on roofs.
Insulation of water pipes.
Filling for floor and roof slabs.
Construction of partition walls and panel walls in framed structures.
Production precast building blocks and low cost housing.