What does the compressive strength of foam concrete depend on?

The compressive strength decreases exponentially with a reduction in density of foam concrete.

The parameters affecting the strength of foam concrete are cement–sand and water–cement ratios, curing regime, type and particle size distribution of sand and type of foaming agent used.

For dry density of foam concrete between 500 and 1000 kg/m3, the compressive strength decreases with an increase in void diameter.

For densities higher than 1000 kg/m3, as the air-voids are far apart to have an influence on the compressive strength, the composition of the paste determines the compressive strength.