Foamed concrete, also known as foamed concrete, cellular concrete, light cellular concrete or reduced density concrete, is defined as a cement-based suspension with a minimum of 20% (by volume) of foam entrained into the plastic mortar. As most coarse aggregates are not used for the production of foam concrete the correct term would be called mortar instead of concrete. It can sometimes be called as "foam cement" or "foam cement" because of the mixing of only cement and foam without any fine aggregate. The density of the foam concrete usually ranges from 400 kg / m 3 to 1600 kg / m 3. The density is usually controlled by totally replacing or part of the fine aggregate with foam.
Foamed concrete, also called cellular lightweight concrete, is produced by mixing Portland cement, sand or fly ash, water and preformed stable foam. The foam is produced with the aid of a foam generator using foaming agent. The air content is typically between 40 to 80 percent of the total volume. The bubbles vary in size from about 0.1 to 1.5 mm in diameter. The foamed concrete differs from (a) the gas or the cellular concrete, where the bubbles form chemically through the reaction of the aluminum powder with the calcium hydroxide and other alkalis released by the hydration of the cement and (b) the Entrained concrete that has a much lower volume of entrained air is used in concrete for durability. The curing of the foamed concrete unit can be made according to IS: 456-2000. Curing can be accelerated by steam.
The foamed concrete may be produced by mixing the above ingredients into a ready-mix plant or ordinary concrete mixer. Foamed concrete is a self-compacting concrete that requires no compaction and will flow easily from a pump outlet to fill the mold, shape, and restricted and irregular cavities. It can be successfully pumped over significant heights and distances. The 28-day strength and the dry density of the material vary by composition, largely because of their air void content, but usually range from 1.0 to 25.00 N / mm 2 and from 400 to 1800 kg / m 3 . The plastic density of the material is about 150 to 200 kg / m 3 higher than its dry density.
APPLICATIONS:
1. Light-weight foamed concrete in the form of bricks, blocks or effluents in situ is used for thermal insulation on flat roofs or for cold walls or as non-load-bearing walls in buildings framed in RCC / steel or for load-bearing walls for Buildings Of low height.
2. The degree of fire of foamed concrete is much higher than that of brickwork or dense concrete.
3. Filling in bulk, using relatively low resistance material, for redundant sewer lines, disused basements and basements, storage tanks, tunnels and subways, etc.
4. Cover the walls of the arched bridges.
5. Fill up the retaining walls and bridge abutment.
6. Stabilization of the soil, for example in the construction of embankment slopes.
7. Grouting for tunnel work.