# Slope Stability Analysis of Open-Pit Mine Considering Weathering Effects
## 4 Slope Stability Evaluation and Discussion
Additionally, when comparing slopes with the same weathering time, an increase in slope height also contributes to a decrease in the safety factor. Overall, it is evident that the safety factor of the slope decreases with both increasing weathering time and slope height. Furthermore, the safety factors for slopes of 50 m and 90 m are found to comply with the specified requirements. However, for a 120 m slope, as the weathering time gradually increases to 28 days, the safety factor diminishes to 1.085, falling below the minimum safety factor stipulated by the specification. For slopes with an angle of 47, it is apparent that an augmentation in the final slope angle leads to a commensurate reduction in the safety factor. After 28 days of weathering, the safety factors for slopes of varying heights are recorded as 1.094, 1.050, and 1.031, all of which are below the minimum safety factor mandated by relevant standards. While these safety factors remain marginally above 1, there is a discernible trend towards instability, particularly for slopes subject to continuous weathering effects [41; 42]. This trend is detrimental to slope stability and may signal a potential risk of failure. Consequently, for slopes exceeding 90 m in height, it is prudent to exercise caution when considering a final \begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Slope Height (m)** & **0 Days** & **7 Days** & **14 Days** & **21 Days** & **28 Days** \\ \hline
50 & 1.788 & 1.773 & 1.753 & 1.538 & 1.130 \\
90 & 1.598 & 1.590 & 1.578 & 1.567 & 1.122 \\
120 & 1.287 & 1.282 & 1.276 & 1.269 & 1.085 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: The safety factors under different heights and weathering times at angle of 45\({}^{\circ}\). \begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Slope Height (m)** & **0 Days** & **7 Days** & **14 Days** & **21 Days** & **28 Days** \\ \hline
50 & 1.720 & 1.705 & 1.683 & 1.599 & 1.094 \\
90 & 1.353 & 1.346 & 1.336 & 1.325 & 1.050 \\
120 & 1.230 & 1.225 & 1.219 & 1.231 & 1.031 \\ \hlineslope angle of 47\({}^{\circ}\). If the intended service life surpasses one month, it is generally advisable to avoid such steep slope angles, as they may jeopardize the long-term stability and safety of the slope. It should be noted that the results obtained through the Fast Lagrangian Analysis of Continua modelling as well as the limit equilibrium methods were based on a reasonable degree of simplification of the models as well as empirical analysis. For example, the boundary conditions and initial stress field were primarily determined by considering the self-weight stress of the rock mass. The obtained numerical results will be also compared with the recorded data in the mine sites in the future. Therefore, the obtained results help us to further understand the effects of weathering on the slope stability, but caution must be taken when using the numerical results as a source of reliable results. The numerical results should be combined with the geological environment conditions, topography, and lithology of the open-pit slope in the mining areas. It is also recommended that further research be conducted in the future and that analysis be undertaken to establish a more explicit relationship between the weathering parameters and the mechanical properties of rock layering at different depths.