Gas silicate

Gas silicate is a variety of cellular materials obtained from a mixture of lime , ground or fine sand and water with gas-forming (pore-forming) additives, using usually autoclave treatment to accelerate hardening. Aluminum powder is often used as a gas-forming additive.

The first attempts to produce gas silicate were made at the beginning of the 20th century. In 1918 - 1920 , the Swedish architect Eriksson developed and improved a new method for the production of gas silicate. In 1924 , a patent was obtained for the material produced. Subsequently, gas silicate was produced by autoclave, first in Sweden, and then in other countries.

Special blocks of GOST 21520-89 standard are made out of gas silicate (it lost its force on the territory of the Republic of Belarus, replaced by STB 1117-98 "Blocks of cellular concrete wall. Specifications"), which are called blocks of cellular concrete . Gas silicate is often compared to foam concrete . With equal strength, the gas silicate will have a lower density and lower thermal conductivity , and with the same density and thermal conductivity it will be stronger.

Gas silicate has certain disadvantages:

• high degree of water absorption - therefore, at a relative humidity of more than 60%, its use is limited;
• relatively low heat resistance - above 400 ° C gas silicate is not used.