Numerical Analysis of the Deformation Performance of Monopile under Wave and Current Load
Abstract
:1. Introduction
2. Numerical Model
2.1. Wave Model
2.2. Monopile-Soil Model
2.3. Wave-Monopile-Soil Coupling Model
3. Model Validation
3.1. Validation of Monopile-Soil Model
3.2. Validation of Wave Model
4. Response of Monopile Foundation under Extreme Marine Condition
5. Parametric Study
5.1. Effect of Pile Diameter and Wall Thickness
5.2. Effect of Embedment Depth and Wall Thickness
5.3. Effect of Pile Diameter and Embedment Depth
6. Conclusions
- (1)
- Under the wave and current load, the monopile performs periodic reciprocating motion, and the pile head is displaced toward the direction of wave motion for most of the time during the whole movement process. Due to the rotation of the pile, the reciprocating motion of the monopile foundation will develop a pile-soil gap around the pile and threaten the stability of the foundation. In extreme environments, it is recommended that people not only focus on the maximum displacement of the foundation, but also monitor the entire process.
- (2)
- When the monopile moves periodically, the soil within the pile close to the mud surface has obvious displacement, while the soil within the pile close to the pile end has small displacement. The rotation center is 10.5 m below the mud surface. The displacement of the soil around the pile at the mud surface is significantly greater than that of the soil at the pile end.
- (3)
- In the extreme marine environment, when the embedment depth remains unchanged, increasing the pile diameter is a better way to improve the lateral bearing capacity of monopile than increasing the wall thickness. When the pile diameter is relatively small, the benefits of increasing the wall thickness are greater.
- (4)
- Under normal circumstances, increasing the embedment depth of the monopile can significantly reduce the deflection of the pile head. However, if the embedment depth is already large enough, other measures like increasing the pile diameter and wall thickness should be taken to improve the lateral bearing capacity of the monopile.
Author Contributions
Funding
Conflicts of Interest
References
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Pile Length (m) | Outer Diameter (mm) | Wall Thickness (mm) | Embedment Depth (m) | Loading Height |
---|---|---|---|---|
2 | 165 | 35.5 | 0 | 6D |
Soil Proportion | Shear Modulus (Pa) | Internal Friction Angle (°) | Effective Cohesion (kPa) | Poisson’s Ratio |
---|---|---|---|---|
2.69 | 4 × 106 | 35.5 | 0 | 0.3 |
Wave Period (s) | Wave Height (m) | Water Depth (m) | Current Speed (m/s) |
---|---|---|---|
7.7 | 6.9 | 20 | 0.8 |
Shear Modulus (Pa) | Poisson’s Ratio | Internal Friction Angle (°) | Effective Cohesion (kPa) |
---|---|---|---|
0.3 | 30 | 4 |
Shear Modulus (Pa) | Poisson’s Ratio | Pile Diameter (m) | Embedment Depth (m) | Thickness (mm) |
---|---|---|---|---|
0.3 | 5 | 16 | 70 |
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Chen, L.; Yang, X.; Li, L.; Wu, W.; El Naggar, M.H.; Wang, K.; Chen, J. Numerical Analysis of the Deformation Performance of Monopile under Wave and Current Load. Energies 2020, 13, 6431. https://doi.org/10.3390/en13236431
Chen L, Yang X, Li L, Wu W, El Naggar MH, Wang K, Chen J. Numerical Analysis of the Deformation Performance of Monopile under Wave and Current Load. Energies. 2020; 13(23):6431. https://doi.org/10.3390/en13236431
Chicago/Turabian StyleChen, Libo, Xiaoyan Yang, Lichen Li, Wenbing Wu, M. Hesham El Naggar, Kuihua Wang, and Jinyong Chen. 2020. "Numerical Analysis of the Deformation Performance of Monopile under Wave and Current Load" Energies 13, no. 23: 6431. https://doi.org/10.3390/en13236431
APA StyleChen, L., Yang, X., Li, L., Wu, W., El Naggar, M. H., Wang, K., & Chen, J. (2020). Numerical Analysis of the Deformation Performance of Monopile under Wave and Current Load. Energies, 13(23), 6431. https://doi.org/10.3390/en13236431