# Design Procedures for Sustainable Structural Concretes Using Wastes and Industrial By-Products
## 3 Results
### Physical Properties  
#### 3.3.1 Water Absorption by Immersion  
The water absorption test by immersion at atmospheric pressure was performed taking into consideration three different weight measurements: dry mass (\(M_{d}\)), saturated mass (\(M_{s}\)), and hydrostatic mass (\(M_{h}\)). For each composition, the three specimens were dried in a ventilated oven at a temperature of \(105\pm 5\)\({}^{\circ}\)C until the difference in mass in a 24 h time interval was below 0.1%. Later, the specimens were immersed in water until the change in mass in a 24 h time interval was below 0.1%, and subsequently the hydrostatic mass was \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{\(q\)} & \multirow{2}{*}{**Mixtures**} & \multicolumn{3}{c}{\(f_{cm}\) **(MPa)**} & \multirow{2}{*}{\(f_{ck}\) **(MPa)**} & \multirow{2}{*}{**Strength Class**} & \multicolumn{3}{c}{\(E_{cm}\) **(GPa)**} \\ \cline{3-3} \cline{5-10}  & & **7 Days** & & & & **28 Days** & & **90 Days** \\ \hline \multirow{5}{*}{0.35} & EAFS6 & 12.86 & 17.54 & 18.09 & 13.54 & C12/15 & 24.79 & 24.58 & 26.49 \\  & EAFS2 & 12.38 & 19.43 & 23.35 & 15.43 & C12/15 & 26.22 & 30.47 & 31.31 \\  & EAFS3A & 10.29 & — & — & — & — & 18.76 & — & — \\  & EAFS4 & 10.61 & 9.43 & 13.17 & 6.59 & — & 25.44 & 22.11 & 31.15 \\ \hline \multirow{2}{*}{0.25} & EAFS8B & 25.20 & 36.17 & — & 33.01 & C30/37 & 34.02 & 37.97 & — \\  & EAFS3B & 18.60 & 26.29 & — & 22.29 & C20/25 & 30.62 & 35.01 & — \\ \hline \multirow{2}{*}{0.20} & EAFS8C & 20.88 & 35.14 & — & 31.14 & C30/37 & 32.43 & 35.79 & — \\  & EAFS5C & 22.02 & 34.91 & — & 30.91 & C30/37 & 31.78 & 35.25 & — \\ \hline \multirow{2}{*}{0.15} & EAFS8D & 22.66 & 35.66 & — & 31.66 & C30/37 & 34.90 & 35.37 & — \\  & REF2 & 18.40 & 27.37 & 35.85 & 24.10 & C20/25 & 24.58 & 27.01 & 30.14 \\ \hline \multirow{2}{*}{0.20} & EAFS8C1 & 17.87 & 31.14 & 39.93 & 27.14 & C25/30 & 32.76 & 37.95 & 39.91 \\ \hline \multirow{2}{*}{0.15} & EAFS8D1 & 15.40 & 29.22 & 36.82 & 25.22 & C25/30 & 29.70 & 36.04 & 36.82 \\  & FRC\_EAFS & 13.60 & 25.09 & 31.64 & 21.09 & C20/25 & 30.07 & 37.37 & 36.74 \\ \hline \hline \end{tabular}
\end{table} 
Table 10: Results of the mechanical properties obtained for the REF1, REF2 and EAFS mixtures. \begin{table}
\begin{tabular}{c c c c} \hline \hline \(q\) & **Mixtures** & **Slump (mm)** & **Slump Class** \\ \hline
0.15 & EAFS8D & 125 & S3 \\ \hline  & REF2 & 160 & S4 \\ \hline
0.20 & EAFS8C1 & 50 & S1 \\ \hline  & EAFS8D1 & 160 & S4 \\
0.15 & FRC\_EAFS & 0 & S1 \\ \hline \hline \end{tabular}
\end{table} 
Table 9: _Cont._measured. The water absorption by immersion at atmospheric pressure (\(W_{i}\)) was calculated using the following equation according to the standard LNEC E 394 [48]:  
\[W_{i}=\frac{(M_{s}-M_{d})}{(M_{s}-M_{h})}\times 100 \tag{5}\]  
For water absorption by immersion under vacuum, three different weight measurements were obtained: dry mass (\(M_{d}\)), saturated mass after water absorption under vacuum (\(M_{s}\)), and hydrostatic mass (\(M_{h}\)). The test consisted of dying the specimens in a ventilated oven at a temperature of \(105\pm 5\)\({}^{\circ}\)C until the mass variation for a 24 h time interval was below 0.1%. The specimens were then subjected to a vacuum pressure of 1 bar for 24 h and water was subsequently introduced slowly, in such a way that the specimens were completely submerged. The vacuum was maintained for an additional 24 h period. The pressure was then released to atmospheric level and the specimens remained submerged for 24 h to ensure full saturation. Lastly, the hydrostatic mass was obtained. The water absorption by immersion under vacuum (\(W_{vc}\)) was calculated using the following equation according to the Standard LNEC E 395 [49]:  
\[W_{vc}=\frac{(M_{s}-M_{d})}{(M_{s}-M_{h})}\times 100 \tag{6}\]  
Tables 11 and 12 show the results of water absorption by immersion at atmospheric pressure and under vacuum, respectively.