The sorption isotherms of the specimens checked, the relative
humidity as a function of the moisture content are shown in
Figs. 11 and 12. Table 3 shows the moisture content per unit mass
(kg/kg) of soil-based foamed concrete for Series I and II under a range of relative humidity from 8.5% to 100%. The sorption isotherms
of soil-based foamed concrete and the moisture content
per unit mass show clearly that the moisture absorption increased
as their densities decreasing. This observation is consistent with
earlier results presented in Ref. [29]. And the results obtained in
this research are useful to determine the hygroscopic sorption of
different specimens.