Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects
Abstract
:1. Introduction
2. Roots’ Mechanical Reinforcement
2.1. Simplified Model
2.2. Triaxial Testing
3. Hydrological Model of Rooted Soils
4. Stability Analyses of Rooted Soil Slopes
4.1. Root Architecture
4.2. Slope Model and Analysis
5. Results and Discussion
5.1. Pore Water Pressure
5.2. Stability Results
6. Conclusions
- (1)
- Ficus virens roots contribute to an increase in the effective cohesion of the root–soil composite, more than 10 kPa, while they do not have much influence on the effective friction angle.
- (2)
- Matric suction in unsaturated soils is proven to be highly associated with root architecture, and an exponential root distribution tends to have more obvious hydrological effects within its influencing zone.
- (3)
- The hydrological contribution to slope stability is greatly influenced by climate change. In a short period of rainfall, the factor of safety considering the hydrological effect alone is higher than that of a bare slope. However, this effect gradually weakens until it disappears.
- (4)
- Rainfall infiltration tends to induce a shallow failure mechanism, and hence, vegetation in practice could work well for the prevention of shallow slope failure.
- (5)
- A conservative outcome is yielded when not considering the hydro-mechanical or even the single reinforcement effect of roots, which is uneconomical in slope design, especially in this era of minimizing carbon emissions.
- (6)
- A soil slope is suggested to be environmentally reinforced by species with a large tensile strength and root area ratio and a leafy superstructure with a high capability of transpiration, aiming to provide more mechanical and hydrological reinforcements for slope stabilization.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Natural Gravity (Kn·m−3) | Natural Water Content | Maximum Dry Density (g·m−3) | Optimum Water Content | Plastic Limit | Liquid Limit | Plasticity Index, IP |
---|---|---|---|---|---|---|
19.7 | 19.36% | 1.83 | 12.35% | 15.52% | 30.92% | 15.4 |
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Qin, C.; Wang, R.; Chen, W.; Shi, Y.; Sun, H.; Tang, J.; Wang, L. Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects. Forests 2024, 15, 133. https://doi.org/10.3390/f15010133
Qin C, Wang R, Chen W, Shi Y, Sun H, Tang J, Wang L. Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects. Forests. 2024; 15(1):133. https://doi.org/10.3390/f15010133
Chicago/Turabian StyleQin, Changbing, Rui Wang, Wenkang Chen, Yusha Shi, Haixiu Sun, Jianjun Tang, and Luqi Wang. 2024. "Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects" Forests 15, no. 1: 133. https://doi.org/10.3390/f15010133
APA StyleQin, C., Wang, R., Chen, W., Shi, Y., Sun, H., Tang, J., & Wang, L. (2024). Stability of Ficus virens-Reinforced Slopes Considering Mechanical and/or Hydrological Effects. Forests, 15(1), 133. https://doi.org/10.3390/f15010133