Wave Load Mitigation by Perforation of Monopiles
The design of large diameter monopiles (8–10 m) at intermediate to deep waters is largely driven by the fatigue limit state and mainly due to wave loads. The scope of the present paper is to assess the mitigation of wave loads on a monopile by perforation of the shell. The perforation design consist...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-05-01
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| Series: | Journal of Marine Science and Engineering |
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| Online Access: | https://www.mdpi.com/2077-1312/8/5/352 |
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| author | Jacob Andersen Rune Abrahamsen Thomas Lykke Andersen Morten Thøtt Andersen Torben Ladegaard Baun Jesper Lykkegaard Neubauer |
| author_facet | Jacob Andersen Rune Abrahamsen Thomas Lykke Andersen Morten Thøtt Andersen Torben Ladegaard Baun Jesper Lykkegaard Neubauer |
| author_sort | Jacob Andersen |
| collection | DOAJ |
| description | The design of large diameter monopiles (8–10 m) at intermediate to deep waters is largely driven by the fatigue limit state and mainly due to wave loads. The scope of the present paper is to assess the mitigation of wave loads on a monopile by perforation of the shell. The perforation design consists of elliptical holes in the vicinity of the splash zone. Wave loads are estimated for both regular and irregular waves through physical model tests in a wave flume. The test matrix includes waves with Keulegan–Carpenter (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula>) numbers in the range 0.25 to 10 and covers both fatigue and ultimate limit states. Load reductions in the order of 6%–20% are found for <inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula> numbers above 1.5. Significantly higher load reductions are found for <inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula> numbers less than 1.5 and thus the potential to reduce fatigue wave loads has been demonstrated. |
| first_indexed | 2024-03-10T19:47:40Z |
| format | Article |
| id | doaj.art-764841f2cca44bd2bec81beb17d877de |
| institution | Directory Open Access Journal |
| issn | 2077-1312 |
| language | English |
| last_indexed | 2024-03-10T19:47:40Z |
| publishDate | 2020-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Marine Science and Engineering |
| spelling | doaj.art-764841f2cca44bd2bec81beb17d877de2023-11-20T00:40:19ZengMDPI AGJournal of Marine Science and Engineering2077-13122020-05-018535210.3390/jmse8050352Wave Load Mitigation by Perforation of MonopilesJacob Andersen0Rune Abrahamsen1Thomas Lykke Andersen2Morten Thøtt Andersen3Torben Ladegaard Baun4Jesper Lykkegaard Neubauer5Division of Reliability, Dynamics and Marine Engineering, Aalborg University (AAU), Thomas Manns Vej 23, 9220 Aalborg Øst, DenmarkDivision of Reliability, Dynamics and Marine Engineering, Aalborg University (AAU), Thomas Manns Vej 23, 9220 Aalborg Øst, DenmarkDivision of Reliability, Dynamics and Marine Engineering, Aalborg University (AAU), Thomas Manns Vej 23, 9220 Aalborg Øst, DenmarkDivision of Reliability, Dynamics and Marine Engineering, Aalborg University (AAU), Thomas Manns Vej 23, 9220 Aalborg Øst, DenmarkVestas Wind Systems A/S, Hedeager 42, 8200 Aarhus N, DenmarkVestas Wind Systems A/S, Hedeager 42, 8200 Aarhus N, DenmarkThe design of large diameter monopiles (8–10 m) at intermediate to deep waters is largely driven by the fatigue limit state and mainly due to wave loads. The scope of the present paper is to assess the mitigation of wave loads on a monopile by perforation of the shell. The perforation design consists of elliptical holes in the vicinity of the splash zone. Wave loads are estimated for both regular and irregular waves through physical model tests in a wave flume. The test matrix includes waves with Keulegan–Carpenter (<inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula>) numbers in the range 0.25 to 10 and covers both fatigue and ultimate limit states. Load reductions in the order of 6%–20% are found for <inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula> numbers above 1.5. Significantly higher load reductions are found for <inline-formula> <math display="inline"> <semantics> <mrow> <mi>K</mi> <mi>C</mi> </mrow> </semantics> </math> </inline-formula> numbers less than 1.5 and thus the potential to reduce fatigue wave loads has been demonstrated.https://www.mdpi.com/2077-1312/8/5/352wave loadsmonopilesperforationhydrodynamicswave flume tests |
| spellingShingle | Jacob Andersen Rune Abrahamsen Thomas Lykke Andersen Morten Thøtt Andersen Torben Ladegaard Baun Jesper Lykkegaard Neubauer Wave Load Mitigation by Perforation of Monopiles Journal of Marine Science and Engineering wave loads monopiles perforation hydrodynamics wave flume tests |
| title | Wave Load Mitigation by Perforation of Monopiles |
| title_full | Wave Load Mitigation by Perforation of Monopiles |
| title_fullStr | Wave Load Mitigation by Perforation of Monopiles |
| title_full_unstemmed | Wave Load Mitigation by Perforation of Monopiles |
| title_short | Wave Load Mitigation by Perforation of Monopiles |
| title_sort | wave load mitigation by perforation of monopiles |
| topic | wave loads monopiles perforation hydrodynamics wave flume tests |
| url | https://www.mdpi.com/2077-1312/8/5/352 |
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