## 2 Methodology
These porous stones were modeled using an \"OPEN\" flow boundary condition on the upper and lower surfaces of the numerical model. These experimental test conditions were replicated in Plaxis2D(r), as shown in Figure 2c,d, for both saturated and unsaturated conditions. This ensures that the numerical simulation accurately reflects the hydraulic and mechanical behavior observed in the experimental tests, ensuring precision in the analysis of controlled consolidation scenarios. For the soil representation in Plaxis2D(r), a soil sample with dimensions of 35 cm in height and 50 cm in diameter was modeled, subjected to gradual loading. These dimensions were chosen due to the same D/H ratio as the laboratory specimen, which has a diameter of 6.3 cm and a height of 2.2 cm. On the other hand, Figure 3 and Table 2 illustrate the logical process to identify each curve analyzed to represent excess and dissipation of pore pressures. The pore pressure dissipation behavior was examined at four height ratios of the soil. As mentioned earlier, this is soil that drains water through its upper and lower boundaries (double drainage), so the drainage distance from the middle of the soil is equal in both upward and downward directions [1]. Figure 3 shows how the model's upper half was analyzed, with H representing the surface and H = 0 indicating the deepest point analyzed. For unsaturated soils, key concepts were used to understand the mechanical and hydraulic behavior of the soil, such as matric suction and effective saturation. Matric  
Figure 3: Analysis control points. \begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline  & \multicolumn{4}{c}{**Saturated**} & \multicolumn{4}{c}{**Unsaturated**} \\ \hline
**Load** & **H = 0** & **H/4** & **H/2** & **3H/4** & **H = 0** & **H/4** & **H/2** & **3H/4** & **H** \\ \hline
10-3200 & SS,Sat,H/4 & SS,Sat,H/2 & SS,Sat,H/4 & SS,60\%,0 & SS,60\%,H/4 & SS,60\%,H/2 & SS,60\%,3H/4 & SS,60\%,H \\ kPa & HS,Sat,H/4 & HS,Sat,H/2 & HS,Sat,H/4 & HS,Sat,H/2 & HS,Sat,H/4 & HS,60\%,0 & HS,60\%,H/4 & HS,60\%,H & HS,60\%,H \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Curve matrix for height ratios. suction is the difference between air pressure and water pressure within the soil pores. This property is linked to the degree of saturation through the soil-water characteristic curve (SWCC). Effective saturation represents the fraction of water retained in the soil that influences effective stress [21; 22], as shown below:  
\[S_{eff}=\frac{S_{r}(\psi)-S_{res}}{S_{sat}-S_{res}} \tag{1}\]  
\(S_{\text{eff}}\) is the effective saturation, \(S_{r}\) (\(\psi\)) is the degree of saturation as a suction function, \(S_{\text{res}}\) is the residual saturation, and \(S_{\text{sat}}\) is the total saturation. Calculating effective water pressure using effective saturation and the total water pressure is possible. \[p_{active}=S_{eff}.p_{w} \tag{2}\]  
where \(p_{\text{active}}\) is the pore pressure acting on the soil skeleton, and \(p_{w}\) is the water pore pressure. Plaxis2\({}^{\text{\textregistered}}\) calculates the soil's effective stress through the contribution of water pressure and suction based on the degree of saturation. \[\sigma^{\prime}=\sigma-p_{active} \tag{3}\]  
To analyze the flow behavior in terms of the SWCC, Plaxis\({}^{\text{\textregistered}}\) describes the evolution of water pressure as a function of the suction level using the adjustment parameters \(g_{a}\) and \(g_{n}\) present in Equation (4). This allows representing the evolution of water pressure under the following equation:  
\[\frac{\text{dS}(p_{w})}{\text{d}_{p_{w}}}=(S_{\text{sat}}-S_{\text{res}}) \left[\frac{1-g_{n}}{g_{n}}\right]\left[g_{n}\left(\frac{g_{a}}{\gamma_{w}} \right)^{\delta_{n}}\cdotp_{w}^{(\delta_{n}-1)}\right]\left[1+\left(g_{a}. \frac{P_{w}}{\gamma_{w}}\right)^{\delta_{n}}\right]^{(\frac{1-2g_{n}}{\delta_{ n}})} \tag{4}\]  
On the other hand, soil permeability decreases as the level of matric suction increases. In other words, it affects the soil's ability to allow water flow.