## 7 Conclusions  
The paper focuses on high embankment slopes as the research subject and is based on the investigation of geological models of the slopes. It employs indoor and outdoor rock and soil experiments as well as a numerical analysis. The main conclusions are as follows:  
1. The influence of water content on stress-strain curves is primarily manifested in the curve shape and the magnitude of the deviator stress peak. Under identical confining pressure, an increase in water content leads to an overall decrease in the stress-strain curve, along with a reduction in the magnitude of the deviator stress peak. Following the attainment of this peak, the curve gradually descends until it becomes flat. Changes in confining pressure result in noticeable alterations to the curve shape at different water contents, indicating that the impact of water content on curve shape is constrained by confining pressure.
2. With the rise of the water content, both the internal friction angle and cohesion of the soil diminish. However, the magnitudes of their being affected by the water content of the soil vary. When the water content increases from 18% to 19%, the internal friction angle drops from 36.05\({}^{\circ}\) to 32.88\({}^{\circ}\), a decrease of 3.17\({}^{\circ}\), with a reduction amplitude of 9%. The cohesion reduces from 89.66 kPa to 63.21 kPa, a decrease of 26.45 kPa, with a reduction amplitude of 29.5%. The aforementioned data suggest that the influence of the water content of the soil on cohesion is significantly greater than that on the internal friction angle. Additionally, the shear strength value of the soil decreases as the water content increases. Moreover, the greater the confining pressure, the higher the shear strength value. At the same time, the greater the confining pressure, the more pronounced the decreasing trend of the shear strength value of the soil.
3. The rigid limit equilibrium analysis indicates that the overall slope stability is satisfactory, with the stability coefficients all exceeding 1.30; the local stability calculation results reveal that the central slope in saturated working conditions exhibits a significantly higher stability coefficient of over 1.35.
4. The safety coefficients of high fill slopes with slope angles of 30\({}^{\circ}\), 40\({}^{\circ}\), and 50\({}^{\circ}\) under a maximum daily rainfall of 220 mm are determined to be 1.318, 1.025, and 0.950, respectively. With the increase in slope angle, there is a corresponding decrease in the safety coefficient by 22.2% and 7.3%. The slope with a 30\({}^{\circ}\) angle meets the evaluation requirements for stability and remains in a fundamentally stable state.
5. Comprehensive assessment of slope stability indicates overall favorable conditions. On-site investigation suggests that surface and shallow-layer instability may be the primary factors contributing to slope instability. It is advisable to implement measures for slope protection.  
**Author Contributions:** Writing and editing. H.Z.; software, C.Z.; methodology, W.Z.; resources, X.W.; supervision, J.Z. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the National Natural Science Foundation of China (51908176) and the Hebei Provincial Key Laboratory of Meteorological and Ecological Environment (Z-1502). Their support is gratefully acknowledged.  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** Data are contained within the article.  
**Conflicts of Interest:** The authors declare no conflicts of interests.