Classification and Uses of Lightweight Concrete

Light Weight Concrete can be classified as

1. Low density concrete
2. Moderate strength concrete
3. Structural concrete

Low Density Concrete

These are employing chiefly for insulation purposes with low unit weight, seldom exceeding 800kg/m³, heat insulation value are high. Compressive strength are low, regarding from about 0.69 to 6.89N/mm2.

Moderate Density Concrete

The use of these concrete requires a fair degree of compressive strength, and thus they fall about midway between the structural and low density concrete. These are sometimes designed as ‘fill’ concrete. Compressive strength are approximately 6.89 to 17.24N/mm² and insulation values are intermediate.

Structural Concrete

Concrete with full structural efficiency contain aggregates which fall on the other end of the scale and which are generally made with expanded shale, clay, slates, slag, and fly-ash. Minimum compressive strength is 17.24N/mm². Most structural LWC are capable of producing concrete with compressive strength in excess of 34.47N/mm². Since the unit weight of structural LWC are considerably greater than those of low density concrete, insulation efficiency is lower. However, thermal insulation values for structural LWC are substantially better than NWC.

Uses of Lightweight Concrete

• Screeds and thickening for general purposes especially when such screeds or thickening and weight to floors roofs and other structural members.
• Screeds and walls where timber has to be attached by nailing.
• Casting structural steel to protect it’s against fire and corrosion or as a covering for architectural purposes.
• Heat insulation on roofs.
• Insulating water pipes.
• Construction of partition walls and panel walls in frame structures.
• Fixing bricks to receive nails from joinery, principally in domestic or domestic type construction.
• General insulation of walls.
• Surface rendered for external walls of small houses.
• It is also being used for reinforced concrete.