## 3 Results and Discussion
### Water Absorption  
Table 8 presents the analysis of variance for water absorption, with 95% reliability. Note that the amount of foam has a greater influence on the absorption of water, as it makes a 50% contribution. The type of cement makes a contribution of 3% and while the type of additive has an influence, its contribution is 1%. The interaction between the factors, the type of cement, the amount of foam and the type of additive make a contribution of 12%. The interaction between the factors of cement type and additive type make a 12% contribution while the interaction between the type of cement and the amount of foam makes the lowest contribution among the factors, this being 8%. The amount of foam and the type of additive make a 9% contribution to the blocks of foamed concrete absorbing water.  
Note from the graph on water absorption due to the types of cement--see Figure 5(a)--that there was a change in the absorption in accordance with the cement used. The CP II-F showed an absorption of 27.0%, CP II-Z-22.5%, and CP V-ARI 24.5%. As expected, the cement to which pozzolanic material was added (CP II-Z), on average, was the one that absorbed the least water, because, according to the literature, when the amount of pozzolanic material is increased, the absorption of water tends to decrease [62].  
According to Figure 5(b), the more foam is added, the greater the water absorption. This occurs due to the increase in total voids and the connectivity between the pores (capillarity) [4; 63].  
What can be seen from Figure 5(c) is the amount of water absorbed due to the types of additives used; the plasticizer and superplasticizer additives present average water absorption of 23.6% and 24.0%,  
Figure 5: The water absorption related to (**a**) cement type, (**b**) foam amount, and (**c**) additive type for different curing times, where the middle point is the mean, the box is the confidence interval (95%), and the whisker shows the standard deviation.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Factor** & \begin{tabular}{c} **Sum of** \\ **Squares** \\ \end{tabular} & \begin{tabular}{c} **Degrees of** \\ **Freedom** \\ \end{tabular} & \begin{tabular}{c} **Mean of** \\ **Squares** \\ \end{tabular} & \begin{tabular}{c} **\(F\)**-Value** \\ \end{tabular} & \
\begin{tabular}{c} **\(p\)**-Value** \\ \end{tabular} &
\begin{tabular}{c} **\% Contribution** \\ \end{tabular} \\ \hline Cement Type (CT) & 347.91 & 2 & 173.95 & 32.59 & 0.0000 & 3.3 \\ Foam Amount (FA) & 5317.99 & 2 & 2659.00 & 498.20 & 0.0000 & 49.7 \\ Additive Type (AT) & 120.47 & 3 & 40.16 & 7.52 & 0.0001 & 1.1 \\ CT*FA & 901.98 & 4 & 225.49 & 42.25 & 0.0000 & 8.4 \\ CT*AT & 1314.68 & 6 & 219.11 & 41.05 & 0.0000 & 12.3 \\ FA*AT & 998.08 & 6 & 166.35 & 31.17 & 0.0000 & 9.3 \\ CT*FA*AT & 1310.15 & 12 & 109.18 & 20.46 & 0.0000 & 12.2 \\ Error & 384.28 & 72 & 5.34 & & 3.6 \\ Total & 10,695.54 & 107 & & & 100.0 \\ \hline \hline \end{tabular}  
* Interaction between factors.  
\end{table}
Table 8: Analysis of variance for water absorption (28 days of curing).  
respectively, compared to the additive incorporating air and to the blocks of foamed concrete without addition of additive, both of which presented an average of 26% absorption of water. The results obtained for water absorption are similar to those found in the literature [64; 65].