Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea
Abstract
1. Introduction
2. Study Area and Observation Devices
3. Materials and Methods
3.1. Rainfall Infiltration Analysis
3.1.1. Unsaturated Flow
3.1.2. Balance of Momentum
3.1.3. Coupled Hydro-Mechanical Analysis
3.2. Slope Stability Analysis
3.3. Material Properties
3.4. Slope Geometry and Boundary and Initial Conditions
4. Results and Discussion
4.1. Site-Specific Rainfall Infiltration Analysis
4.2. Slope Stability Assessment
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Parameter | Value | |
---|---|---|
Dry density of soil, | 1250 kg/m3 | |
Initial porosity, no | 0.46 | |
Soil classification (USCS) | SP–SM | |
Cohesion, | 0.1 × 103 Pa | |
Friction angle, | 33° | |
Dilation angle, | 0° | |
Bulk modulus, K | 33.3 × 106 Pa | |
Shear modulus, G | 11.1 × 106 Pa | |
Hydraulic conductivity, ks | 1.97 × 10−6 m/s | |
Soil-water characteristics (wetting) | Residual saturation, Sr | 0 |
P0 | 3000 Pa | |
van Genuchten parameter, a | 0.52 | |
Constant in relative permeability for water, b | 0.5 | |
Constant in relative permeability for air, c | 0.5 | |
Viscosity ratio, | 56 | |
Water density, | 1000 kg/m3 | |
Air density, | 1.25 kg/m3 | |
Bulk modulus of water, Kw | 2 × 109 Pa | |
Bulk modulus of air, Ka | 1 × 105 Pa |
Fluid Flow Model | Relative Permeability Model | Mean | Standard Deviation | ||
---|---|---|---|---|---|
Depth = 0.5 m | Depth = 1.0 m | Depth = 0.5 m | Depth = 1.0 m | ||
sp-flow | vG–M | −0.224 | −0.164 | 0.409 | 0.115 |
mvG–M | 0.037 | −0.071 | 0.057 | 0.027 | |
Kr–sp–FLAC | 0.041 | −0.055 | 0.065 | 0.11 | |
CHM | vG–M | −0.223 | −0.164 | 0.41 | 0.114 |
mvG–M | 0.03 | −0.068 | 0.055 | 0.026 | |
Kr–sp–FLAC | 0.036 | −0.063 | 0.061 | 0.1 |
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Kang, S.; Lee, S.-R.; Cho, S.-E. Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea. Sustainability 2020, 12, 2839. https://doi.org/10.3390/su12072839
Kang S, Lee S-R, Cho S-E. Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea. Sustainability. 2020; 12(7):2839. https://doi.org/10.3390/su12072839
Chicago/Turabian StyleKang, Sinhang, Seung-Rae Lee, and Sung-Eun Cho. 2020. "Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea" Sustainability 12, no. 7: 2839. https://doi.org/10.3390/su12072839
APA StyleKang, S., Lee, S.-R., & Cho, S.-E. (2020). Slope Stability Analysis of Unsaturated Soil Slopes Based on the Site-Specific Characteristics: A Case Study of Hwangryeong Mountain, Busan, Korea. Sustainability, 12(7), 2839. https://doi.org/10.3390/su12072839