Research on Stability of Dam Substation on Inclined Soft Soil Foundation Reinforced by Pile Foundation
Abstract
:1. Introduction
2. Numerical Model Establishment
2.1. Establishment of the Model
- (1)
- Model overview
- (2)
- Model setting
2.2. Safety Factor and Deformation of Pileless Slope
3. Analysis of Results
3.1. The Influence of Different Soft Soil Foundation Inclination Angles
3.2. The Influence of Different Pile Spacing
3.3. The Influence of Different Pile Lengths
3.4. Displacement and Stress of Piles
4. Conclusions
- (1)
- The increase in the soft soil layer thickness will reduce the safety factor of the slope and affect the distribution of the vertical displacement equipotential surface. In the engineering design process, the influence of soft soil layers in the actual formation should be considered.
- (2)
- Pile foundation reinforcement of the dam slope on an inclined soft soil foundation can effectively reduce slope deformation and improve the slope safety factor. The reduction in pile spacing and the increase in piles can significantly reduce the deformation of the dam slope. Pile layout has a significant effect on the stability of slope foundations, but the change in pile spacing has no significant effect on the settlement surface of the slope bottom.
- (3)
- Pile length increase can significantly reduce slope deformation; when the pile length exceeds a certain range, the slope deformation reaches a very small stable value. As the pile length increases, the deformation stabilizes. Therefore, it is important to set the pile length appropriately in actual engineering design, to avoid material waste.
- (4)
- The pile side force is mainly distributed in the range of 0~2 m from the top of the pile, and the main deformation is the lateral deformation of the upper part of the pile. The foundation deformation is primarily resisted by the piles on both sides, and the lateral deformation in the middle position is smaller. In the actual project, it is necessary to set a reasonable number of piles and pile spacing to ensure the stability of the slope while improving the utilization of materials.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Projects | Elastic Modulus (MPa) | Poisson’s Ratio | Unit Weight (kN/m3) | Cohesion (kPa) | Friction Angle (°) |
---|---|---|---|---|---|
Slope | 100 | 0.35 | 19 | 20 | 25 |
Soft soil | 10 | 0.35 | 18 | 10 | 0 |
Subsoil | 250 | 0.25 | 23 | \ | \ |
Pile | 30,000 | 0.2 | \ | \ | \ |
Projects | Pile Length/m | Pile Spacing/m | Pile Diameter/m | Safety Factor |
---|---|---|---|---|
With piles | 6 | 4 | 0.8 | 4 |
Without piles | / | / | / | 1.52 |
θ2 | 5° | 6° | 7° |
Safety factor | 4 | 4 | 3.9 |
Working Condition | Pile Length /m | Pile Diameter/m | Pile Spacing/m | Number of Piles | Safety Factor |
---|---|---|---|---|---|
1 | 6 | 0.8 | 2 | 10 | 4 |
2 | 6 | 0.8 | 2.5 | 9 | 4 |
3 | 6 | 0.8 | 3 | 8 | 4 |
4 | 6 | 0.8 | 4 | 6 | 4 |
5 | 6 | 0.8 | 3 | 6 | 3.4 |
Working Condition | Pile Length/m | Pile Diameter/m | Pile Spacing/m | Maximum Deformation/mm | Safety Factor |
---|---|---|---|---|---|
1 | 3 | 0.8 | 4 | 250.6 | 3.6 |
2 | 5 | 0.8 | 4 | 6.0 | 4 |
3 | 6 | 0.8 | 4 | 5.8 | 4 |
4 | 7 | 0.8 | 4 | 5.3 | 4 |
5 | 8 | 0.8 | 4 | 5.3 | 4 |
6 | 10 | 0.8 | 4 | 5.2 | 4 |
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Lin, J.; Yu, S.; Luo, Y.; Xu, T.; Lin, Y.; Zheng, W.; Li, W.; Wang, Y. Research on Stability of Dam Substation on Inclined Soft Soil Foundation Reinforced by Pile Foundation. Water 2023, 15, 3527. https://doi.org/10.3390/w15203527
Lin J, Yu S, Luo Y, Xu T, Lin Y, Zheng W, Li W, Wang Y. Research on Stability of Dam Substation on Inclined Soft Soil Foundation Reinforced by Pile Foundation. Water. 2023; 15(20):3527. https://doi.org/10.3390/w15203527
Chicago/Turabian StyleLin, Jisheng, Shaowen Yu, Yunhua Luo, Teng Xu, Yuequ Lin, Weiwen Zheng, Wanxun Li, and Yuke Wang. 2023. "Research on Stability of Dam Substation on Inclined Soft Soil Foundation Reinforced by Pile Foundation" Water 15, no. 20: 3527. https://doi.org/10.3390/w15203527
APA StyleLin, J., Yu, S., Luo, Y., Xu, T., Lin, Y., Zheng, W., Li, W., & Wang, Y. (2023). Research on Stability of Dam Substation on Inclined Soft Soil Foundation Reinforced by Pile Foundation. Water, 15(20), 3527. https://doi.org/10.3390/w15203527