## 2 Materials and Methods
### Experimental Methodology  
#### 2.3.1 Preparation of Seawater Solutions  
Based on seawater sampling results from the coastal area surrounding the test soil, sea crystals were used to simulate the salinity of actual seawater in the laboratory. The required amount of sea crystals was weighed and dissolved in a beaker, then cooled to room temperature. The beaker and glass stirring rod were rinsed 2-3 times with distilled \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Sample**} & \multicolumn{4}{c}{**Cementitious Materials**} & \multicolumn{4}{c}{**Admixtures**} & \multirow{2}{*}{**W/C**} & \multirow{2}{*}{**C/S**} \\ \cline{2-2} \cline{6-9}  & **ACP** & & & & & & & & \\ \hline G1 & 12.5 & 62.5 & 25.0 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G2 & 25.0 & 62.5 & 12.5 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G3 & 0 & 75.0 & 25.0 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G4 & 25.0 & 75.0 & 0 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G5 & 12.5 & 75.0 & 12.5 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G6 & 25.0 & 50.0 & 25.0 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ G7 & 16.7 & 66.6 & 16.7 & / & 0.5 & 0.05 & 0.6 & 0.2 \\ GC & / & / & / & 100 & 0.5 & 0.05 & 0.6 & 0.2 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Relative percentages of each component (%). \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline
**Composition** & **SiO\({}_{\mathbf{2}}\)** & **CaO** & **Al\({}_{\mathbf{2}}\)O\({}_{\mathbf{3}}\)** & **SO\({}_{\mathbf{3}}\)** & **MgO** & **Fe\({}_{\mathbf{2}}\)O\({}_{\mathbf{3}}\)** & **Na\({}_{\mathbf{2}}\)O** & **TiO\({}_{\mathbf{2}}\)** & **LOI** \\ \hline GGBS & 29.37 & 40.82 & 14.12 & 0.20 & 1.32 & 8.02 & 0.46 & 0.36 & 1.12 \\ ACP & 21.35 & 57.03 & 6.45 & 3.69 & 3.10 & 4.01 & 0.32 & 0.75 & 0.28 \\ DA & 8.03 & 42.94 & 4.80 & 18.43 & 0.22 & 0.49 & 0.06 & 0.25 & 16.56 \\ OPC & 27.61 & 48.98 & 4.93 & 1.85 & 2.32 & 3.39 & 0.21 & 0.47 & 3.66 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Chemical composition of main materials (%). water, and the rinsing liquid was transferred to a container and mixed by shaking. When adding water to the volumetric flask to within 1-2 cm below the meniscus, a pipette was used to adjust the water level precisely to the meniscus. The bottle was then tightly sealed and gently shaken to mix the solution evenly. Preparation and Basic Performance Testing of Stabilized Soft Soil Samples  
Preparation of stabilized soil and cement soil samples  
A specified amount of soft soil was weighed and added to the mixing pot. This was mixed with the prepared SWC slurry or cement slurry. The mixer was started and stirred at low speed for 120 s, followed by a 15 s stop to scrape down the mixing blade and pot walls. Mixing was then resumed at high speed for another 120 s, completing the preparation of the stabilized soil/cement soil mixture. The mixture was poured into a 40 mm \(\times\) 40 mm \(\times\) 40 mm square mold. After numbering, the test mold was placed in a constant temperature curing box and sealed in a bag. The sample was demolded 24 h after molding, taking care to avoid damage. The specimen was numbered and sealed in a bag until it reached the required curing age for the next test. The compression test must be performed using a compression-testing machine. The compression surfaces are the two sides of the specimen formed during molding, each with an area of 40 mm \(\times\) 40 mm. The loading speed of the press should be set to 1 mm/min. The compressive strength was tested using a CDT1305-2 (MTS, Minneapolis, MN, USA) electronic pressure testing machine, following Equation (1). \[G_{c}=\frac{F_{c}\times 1000}{A} \tag{1}\]  
where \(G_{c}\) is the compressive strength (MPa); \(F_{c}\) is the press reading (kN); and \(A\) is the compression area (mm\({}^{2}\)). Water resistance test  
Water resistance coefficient is an index to measure the water resistance of stabilized soil and cement soil samples. After curing for 28 d, the compressive strength (\(T_{0}\)) of the sample was obtained by testing.