## 5 Conclusions
\begin{table}
\begin{tabular}{c c c c c c c c c c c c} \hline \hline  & \multicolumn{10}{c}{**Biopolymer**} \\ \cline{2-13}
**Biopolymer** & \multicolumn{2}{c}{**CS**} & \multicolumn{2}{c}{**CMC**} & \multicolumn{2}{c}{**XG**} & \multicolumn{2}{c}{**FBPC**} & \multicolumn{2}{c}{**WS**} \\ \cline{2-13}
**Concentration** & \multicolumn{2}{c}{**(wt\%)**} & \multicolumn{2}{c}{**Penetration Resistance (N)**} & \multicolumn{2}{c}{**(wt\%)**} & \multicolumn{2}{c}{**(wt\%)**} & \multicolumn{2}{c}{**(wt\%)**} & \multicolumn{2}{c}{**(wt\%)**} \\ \cline{2-13} \cline{6-13}
**Medium-grained sand** & & & & & & & & & & \\ \hline
0.13 (XG = 0.05) & 1.14 & 0.61 & 0.98 & 0.00 & 2.21 & 0.79 & 0.98 & 0.00 & 0.98 & 0.00 \\
0.25 (XG = 0.13) & 1.55 & 0.52 & 1.14 & 0.23 & 2.70 & 0.93 & 1.06 & 0.18 & 0.98 & 0.00 \\
0.50 (XG = 0.25) & 3.84 & 1.08 & 1.80 & 0.46 & 3.92 & 1.42 & 1.23 & 0.25 & 1.55 & 0.34 \\
0.75 (XG = 0.38) & 5.89 & 1.88 & 4.09 & 0.23 & 3.84 & 0.96 & 2.13 & 0.23 & 0.98 & 0.00 \\
1.00 (XG = 0.50) & 8.09 & 1.94 & 3.43 & 1.10 & 4.01 & 2.51 & 1.96 & 0.75 & 1.55 & 0.52 \\
1.25 (XG = 0.63) & 10.95 & 3.39 & 3.68 & 1.09 & 5.56 & 1.08 & 2.04 & 0.34 & 1.72 & 0.37 \\
1.50 (XG = 0.75) & 7.11 & 1.94 & 5.23 & 0.54 & 4.58 & 1.12 & 2.45 & 0.40 & 1.72 & 0.47 \\ \hline Fine-grained silica sand & & & & & & & & & & \\ \hline
0.13 (XG = 0.05) & 0.50 & 0.00 & 0.65 & 0.23 & 0.98 & 0.28 & 0.74 & 0.25 & 0.50 & 0.00 \\
0.25 (XG = 0.13) & 0.90 & 0.34 & 0.90 & 0.44 & 0.90 & 0.18 & 0.74 & 0.25 & 0.57 & 0.18 \\
0.50 (XG = 0.25) & 1.06 & 0.18 & 0.98 & 0.00 & 1.55 & 0.6 & 0.74 & 0.25 & 0.82 & 0.37 \\
0.75 (XG = 0.38) & 2.04 & 0.82 & 1.39 & 0.34 & 1.72 & 0.47 & 1.39 & 0.44 & 1.14 & 0.23 \\
1.00 (XG = 0.50) & 2.53 & 1.00 & 1.14 & 0.37 & 1.23 & 0.25 & 1.39 & 0.34 & 1.55 & 0.60 \\
1.25 (XG = 0.63) & 3.76 & 1.12 & 2.04 & 0.60 & 1.14 & 0.23 & 1.96 & 0.57 & 0.90 & 0.18 \\
1.50 (XG = 0.75) & 3.60 & 0.88 & 1.96 & 0.85 & 1.80 & 0.54 & 2.78 & 1.22 & 1.31 & 0.37 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Results of Phase 1 penetrometer tests. Penetration resistance of medium-grained sand and fine-grained silica sand samples treated at different biopolymer concentrations. Tests were performed on day 28 after initial treatment (after the fifth and last wind tunnel cycles). Each of the three prepared samples was penetrated at the top and bottom of the centre (n = 6). \begin{table}
\begin{tabular}{c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Application Rate (L/m\({}^{2}\))**} & \multicolumn{6}{c}{**Biopolymer**} \\ \cline{2-10}  & \multicolumn{2}{c}{**CS**} & \multicolumn{2}{c}{**CMC**} & \multicolumn{2}{c}{**XG**} & \multicolumn{2}{c}{**FBPC**} & \multicolumn{2}{c}{**WS**} \\ \cline{2-10}  & \multicolumn{6}{c}{**Penetration Resistance (N)**} \\ \cline{2-10}  & **M** & **SD** & **M** & **SD** & **M** & **SD** & **M** & **SD** & **M** & **SD** \\ \hline \multicolumn{10}{l}{Medium-grained sand} \\ \hline
0.2 & 1.39 & 0.60 & 0.65 & 0.23 & 0.49 & 0.01 & 0.57 & 0.18 & 0.57 & 0.18 \\
0.3 & 0.82 & 0.23 & 1.06 & 0.34 & 0.98 & 0.00 & 0.98 & 0.00 & 0.82 & 0.23 \\
0.4 & 0.98 & 0.00 & 1.59 & 0.33 & 1.14 & 0.23 & 1.23 & 0.37 & 0.82 & 0.23 \\
0.5 & 1.14 & 0.61 & 1.80 & 0.46 & 2.21 & 0.79 & 2.13 & 0.23 & 1.55 & 0.34 \\
0.6 & 0.82 & 0.23 & 2.21 & 0.55 & 2.29 & 0.67 & 1.88 & 0.34 & 0.98 & 0.00 \\ \hline \multicolumn{10}{l}{Fine-grained silica sand} \\ \hline
0.2 & 0.74 & 0.25 & 0.49 & 0.00 & 0.49 & 0.00 & 0.57 & 0.18 & 0.49 & 0.00 \\
0.3 & 0.74 & 0.25 & 0.41 & 0.18 & 0.57 & 0.18 & 0.82 & 0.23 & 0.74 & 0.25 \\
0.4 & 1.06 & 0.44 & 1.06 & 0.18 & 0.82 & 0.23 & 1.06 & 0.18 & 1.23 & 0.37 \\
0.5 & 0.90 & 0.34 & 0.98 & 0.00 & 0.90 & 0.18 & 1.39 & 0.34 & 0.90 & 0.18 \\
0.6 & 1.14 & 0.23 & 1.64 & 0.67 & 1.23 & 0.25 & 1.55 & 0.44 & 2.53 & 0.96 \\ \hline \hline \end{tabular} Note. Plateau concentrations on medium-grained sand (CS = 0.13 wt%, CMC = 0.50 wt%, XG = 0.05 wt%, FBPC = 0.75 wt%, and WS = 0.50 wt%) and on fine-grained silica sand (CS = 0.25 wt%, CMC = 0.50 wt%, XG = 0.13 wt%, FBPC = 1.00 wt%, and WS = 1.25 wt%).  
\end{table} 
Table 5: Results of Phase 2 penetrometer tests.