## 4 SoilWorks Numerical Simulation
### Sensitivity Analysis
#### 4.2.4 Analysis Results
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{\begin{tabular}{c} **SM** \\ **SM** \\ \end{tabular} } & \multicolumn{2}{c}{\begin{tabular}{c} _Mmax_ \\ **Percentage Change** \\ \end{tabular} } & \multicolumn{2}{c}{\
\begin{tabular}{c} _Dmax_ \\ **Percentage Change** \\ \end{tabular} } & \multicolumn{2}{c}{
\begin{tabular}{c} _Favg_ \\ **Percentage Change** \\ \end{tabular} } \\ \cline{2-7}  & **SoilWorks** & **PLAXIS** & **SoilWorks** & **PLAXIS** & **SoilWorks** & **PLAXIS** \\ \hline _0.8\(\Phi\)_ & 121\% & 139\% & 124\% & 157\% & 114\% & 122\% \\ _0.9\(\Phi\)_ & 110\% & 117\% & 110\% & 119\% & 106\% & 108\% \\ _1.0\(\Phi\)_ & 100\% & 100\% & 100\% & 100\% & 100\% & 100\% \\ _1.1\(\Phi\)_ & 93\% & 89\% & 94\% & 91\% & 95\% & 96\% \\ _1.2\(\Phi\)_ & 88\% & 81\% & 90\% & 86\% & 91\% & 93\% \\ \hline \hline \end{tabular}
\end{table} 
Table 8: Sensitivity of friction angle for sandy layers in PLAXIS and SoilWorks. Figure 11: Comparison of the sensitivity of PLAXIS and SoilWorks programs to clay (undrained): **(a)** friction angle (_Dmax_); **(b)** friction angle (_Fargo_). Figure 10: Comparison of the sensitivity diagrams for clay (undrained): **(a)** SoilWorks programs compared for friction angle (_Mmax_, _Dmax_ and _Fargo_); **(b)** PLAXIS and SoilWorks programs compared for friction angle (_Mmax_). Figure 9: Comparison of the sensitivity of PLAXIS and SoilWorks programs to sandy soil (drained): **(a)** friction angle (_Dmax_); **(b)** friction angle (_Fargo_). * Sensitivity Analysis of Soil Elastic Modulus  
The results for different assumed geological conditions were integrated, including sandy soil and clay (drained and undrained) soil, and an integrated analysis was conducted. The maximum bending moment (_Mmax_), maximum displacement (_Dmax_), and average axial force (_Favg_) corresponding to the assumed soil elastic moduli of 50%, 75%, 100%, 150%, and 200% were compared with the maximum bending moment, maximum displacement, and average axial force at the original soil elastic modulus (100%). The percentage change in the maximum bending moment, maximum displacement, and average axial force due to the variation in soil elastic modulus was calculated. The sensitivity of the soil elastic modulus (_E_) on these three parameters (_Mmax_, _Dmax_, _Favg_) is discussed. The analysis results from [PERSON] et al. 's [26] PLAXIS program are also considered. (1) Sandy Soil  
From the summarized analysis results in Table 14, it can be observed that when the soil elastic modulus varies from 50% to 200% of the baseline value (100%) in sandy soil, the range of variation in the maximum bending moment (_Mmax_) is 280.69 to 371.32 kN-m, with a percentage change of 87% to 115%. The range of variation in the maximum displacement (_Dmax_) is 23.941 to 48.483 mm, with a percentage change of 73% to 147%. The range of variation in the average axial force (_Favg_) is 246.1 to 251.7 kN/m, with a percentage change of 100% to 103%. Line graphs depicting the percentage change in the three parameters (_Mmax_, _Dmax_, _Favg_) with respect to different soil elastic moduli were plotted. From Figure 12a, it can be observed that the sensitivity of the soil elastic modulus (_Es_) in sandy soil is more significant for _Mmax_ and _Dmax_, with _Dmax_ showing a maximum increase of 47% when \(E\) is decreased by 50% and a maximum decrease of approximately 27% when \(E\) is increased by 200%. The results indicate that the variation in _Mmax_ and _Dmax_ is more pronounced when the soil elastic modulus is higher or lower, while the effect on Favg is relatively small. Additionally, the sensitivity analysis results for the soil elastic modulus in sandy soil from [PERSON] et al. 's [26] PLAXIS program were compared with the SoilWorks program. From Table 15 and Figures 12b and 13a,b, it can be observed that PLAXIS is more sensitive to variations in _Dmax_ than the SoilWorks program when the soil elastic modulus in sandy soil is smaller.