# Expansive Soil Stabilization with Time, Cement, and Silica Fume
## 4 Presentation and Discussion of Test Results
### Grouting Models  
To simulate the field, it was suggested to maintain a process for grouting using lime, cement and silica fume. The selected percentage of materials was mixed with water and grouted in the soil at a pressure of 0.15-0.25 bar. The load-settlement relationship for untreated soil is shown in Figure 8. The load-settlement relationships for the soil treated with lime, cement and silica fume are shown in Figures 9-11. The failure load is considered  
Figure 6: Free swell for different percentages of additives. Figure 7: Swelling pressure for different percentages of additives. to correspond to a settlement of 10% of the footing width. The summary of the pressure at failure (i.e., at a 10% settlement ratio) is illustrated in Table 6.  
Figure 8: Pressure–settlement relationship for untreated soil. Figure 10: Pressure–settlement relationship for soil grouted with cement. Figure 9: Pressure–settlement relationship for soil grouted with lime. The bearing capacity ratio is defined as follows:  
\[BCR=\frac{\textit{Bearing capacity of footing on treated soil}}{\textit{ bearing capacity of footing on untreated soil}} \tag{2}\]  
The pozzolanic reactions that occur in the lime-soil, cement-soil or silica fume-soil mixtures that lead to strength gain over time are the causes of the reduction in swelling (the liberated silica and alumina combine with the calcium from the lime to produce cement) [22]. Overall, the lime, cement or silica fume stabilization process's flocculation and agglomeration phases produce soil that is easier to mix, work with and finally compact. This lime is believed to be helpful as a soil stabilizer, a mortar binder, a neutralizing agent for water and sewage treatment and a method to maintain alkaline conditions while processing minerals. A well-known stabilizing ingredient is Ca(OH)\({}_{2}\), which is hydrated high-calcium lime that is readily available locally. When it comes to soil stabilization, hydrated lime has been widely shown to be superior to other types of lime. This is due to its straightforward application and small particle size, which facilitates soil blending. The behavior of grout could influence the strength of the entirety [29, 30], which could be reviewed with relative studies. Uncertainty analysis [31] and complex stress conditions [32] are important challenges to geotechnical analysis. The results could be applied in the future with optimum parameters in a field study considering unknown stress and environmental conditions. \begin{table}
\begin{tabular}{c c c c} \hline \hline  & Pressure (kPa) & \multicolumn{2}{c}{Soil type} \\ \hline  & 56.5 & \multicolumn{2}{c}{Untreated} \\ \hline
9\% & 7\% & 5\% & Additive percent \\ \hline
351.1 & 239.8 & 167.3 & Treated with lime \\ \hline
249.4 & 205.3 & 160.9 & Treated with cement \\ \hline
318.8 & 210.7 & 164.8 & Treated with silica fume \\ \hline  & Bearing capacity ratio (BCR) & \multicolumn{2}{c}{Soil type} \\ \hline
6.203 & 4.244 & 2.956 & Treated with lime \\ \hline
4.406 & 3.634 & 2.843 & Treated with cement \\ \hline
5.632 & 3.729 & 2.912 & Treated with silica fume \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Applied pressure at failure and bearing capacity ratio. Figure 11: Pressure–settlement relationship for soil grouted with silica fume. In the work of [PERSON] et al. [33], an expansive soil was stabilized using additives such as cement, zeolite powder, steel slag, fly ash, and blast furnace slag, and its affects on the swelling potential were examined at various curing durations and additive concentrations. The direct shear test was used to examine how the additives affected the strength of the swelling soil. The findings showed that the specimens' no-loading swelling potential could be greatly reduced by 82.5% over the course of 28 days of curing, and their cohesiveness could be significantly boosted by 82% with a 9% cement concentration. Cement can also change clay minerals that are hydrophilic into clay minerals that are non-hydrophilic. When a steel slug was used, the swelling potential was reduced.