## 2 Materials and Methods
### Sampling and Testing  
Mozishan Park in Shenyang city, China, is the site from where the soil sample was collected. This whole area consists of many slopes, and landsliding happens occasionally. The soil at this specific site consists of clay and clayey sand. Soil samples were collected with the help of a drilling machine having 6 inches diameter. Figure 2 presents the site area (Coordinates: 41.666943, 123.477476). A total of ten boreholes were drilled to collect samples at almost every corner and central position of the site. After sample collection, all necessary and required laboratory tests were performed, such as the triaxial test, moisture content test and direct shear test. In situ direct shear tests and triaxial tests are conducted in the laboratory to find out the material properties. The Mohr-Coulomb envelope criteria are used to compute the cohesion and friction of soil. The general form of Mohr-Coulomb criteria is shown in Equation (1). \[\tau=c+\sigma\tan\Phi \tag{1}\]  
Table 1 presents all the material properties achieved in the experimental analysis. Figure 1: Landslide in Washington—18 February 2020 [23]. According to the actual site condition, a 2D slope was modeled in Slide (2D limit equilibrium software) for further analysis. The coordinates of the slope are mentioned in Figure 3. System international (SI) units were used in this analysis. Figure 3 presents the slope model, including the coordinates of each corner that were considered in this analysis. Figure 4 is the methodology flowchart. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Material Number** & **Cohesion (kPa)** & **Friction Angle (Degrees)** & **Unit Weight (kN/m3)** \\ \hline
1 & 25 & 36 & 16.5 \\
2 & 25.8 & 35.5 & 16.2 \\
3 & 26 & 35 & 15.9 \\
4 & 26.3 & 34.6 & 15.5 \\
5 & 26.9 & 34.2 & 15.1 \\
6 & 27.4 & 33.7 & 14.8 \\
7 & 28 & 33.2 & 14.4 \\
8 & 28.5 & 31.8 & 14 \\
9 & 29 & 31.4 & 13.6 \\
10 & 29.4 & 30.9 & 13.1 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Material properties. Figure 2: Mozishan Park site area [24]. Figure 4: Methodology flowchart. Figure 3: Slope model with coordinates. Comparative modeling of soil behavior with the influence of different soil parameters is an important research area for and many studies [25; 26; 27; 28; 29; 30; 31] have been conducted. In the case of weak soil strength, which needs improvement, there are many methods to improve the soil shear strength. For instance, diatomic species increased both residual and peak shear strength of soil [32]. Similarly, the occurrence of landslides is a geohazard problem that affects many regions of the world [33]. Landslides may occur due to natural events such as earthquakes, rain, volcanic eruption and also by manmade changes to the ground and slopes. Most landslide events occur due to the low value of shear strength. By using linear regression analysis, prediction equations have been developed in this research paper. Statistical package for the social sciences (SPSS) software is used to compute the linear correlations between shear strength of soil, slope angle and shear stress. SPSS is normally used for analyzing complex mathematical data to find correlations between different variables. It can perform both linear and non-linear regression analyses. In this paper, the Chinese site is considered, and the material properties are computed by different laboratory tests such as Atterberg limits, sieve analysis, triaxial test and moisture content test. Table 1 presents the material properties. \(\beta\) range is kept between 70 and 88 degrees. This is because the most critical \(\beta\) value is in the range of 60 to 90 degrees. A total of 10 different material types are considered out of the 10 boreholes. After all necessary laboratory testing, the material properties ranges came out to be:  
Unit weight: 13.10 to 16.50 (kN/m\({}^{3}\)), cohesion: 25.00 to 29.00 (kPa), friction angle: 30 to 36 degrees and slope angle: 70 to 88 degrees.