Driving energy losses for constant diameter and tapered submerged monopiles
In: Applied Ocean Research. CML Publications/Elsevier: Southampton. ISSN 0141-1187; e-ISSN 1879-1549, meer
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| Trefwoord |
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| Author keywords |
Monopile installation; Driveabiity; Energy losses; Monopile |
| Auteurs | | Top |
- Vantomme, F., meer
- Versteele, H.
- Cathie, D., meer
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| Abstract |
Large monopiles are used as foundations for offshore wind turbines and are generally designed with a tapered section or conical shape. Some loss of driving energy is expected to occur during installation of these structures due to the submerged section of the tapered monopile. The current literature on this subject is limited and indicates rather large losses compared to field observations. A numerical model of the monopile-water-soil system was set up in the general-purpose finite element package Abaqus. By simulating the hammer impact and the resulting stress wave propagation through the monopile and water, the energy losses to be expected can be calculated accurately. The model was verified against independent finite element analyses and experimental data. A parametric study was performed and the effect of hammer characteristics, submerged monopile length and monopile geometry on the driving energy losses were quantified. The results enable a simple relationship between the energy losses and the monopile geometry to be proposed which increases linearly with pile diameter, taper angle, and submerged length. The losses are typically on the order of 0.15-0.3% per metre submerged length for large tapered monopiles. |
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