Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines
The interface behavior between a caisson and the surrounding soil plays an important role in the installation of suction caissons as foundations for offshore wind turbines. A series of shear tests were carried out using a modified direct shear apparatus to study the interface shear behavior between...
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MDPI AG
2020-11-01
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| Series: | Energies |
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| Online Access: | https://www.mdpi.com/1996-1073/13/22/5866 |
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| author | Wang-chun Zhang Hao Jing Hai-lei Kou |
| author_facet | Wang-chun Zhang Hao Jing Hai-lei Kou |
| author_sort | Wang-chun Zhang |
| collection | DOAJ |
| description | The interface behavior between a caisson and the surrounding soil plays an important role in the installation of suction caissons as foundations for offshore wind turbines. A series of shear tests were carried out using a modified direct shear apparatus to study the interface shear behavior between sand and concrete. Sand samples with three particle size ranges (0.63–1.25 mm, 1.25–2.5 mm, 2.5–5.0 mm) and concrete plates with different relative roughness were used to explore the influence of the relative roughness parameter (<i>R</i><sub>n</sub>) and mean particle size (<i>D</i><sub>50</sub>) on shear behavior. The responses from the pure sand shear test are also discussed for comparison. Test results show that the higher the relative roughness (<i>R</i><sub>n</sub>), the greater the maximum shear stress (<i>τ</i><sub>max</sub>) appeared. The interface shear stress was weaker than that of the pure sand test. Furthermore, the interface friction angle (<i>φ</i>) of sand–concrete was closely related to the relative roughness of the concrete surface. Under the same conditions, the interface friction angle (<i>φ</i>) increased with relative roughness due to the effect of sand particles breakage and redistribution. By contrast, the effect of the mean particle size (<i>D</i><sub>50</sub>) on the interface friction angle (<i>φ</i>) was less significant. However, for the pure sand shear test, the friction angle (<i>φ</i>′) obtained from the traditional shear test apparently increased with <i>D</i><sub>50</sub>, indicating that the friction angle was more affected by <i>D</i><sub>50</sub> in the pure sand test than in the interface shear test. |
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| id | doaj.art-b3cd6c1417d64d0b9e3bd267543129cd |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T14:58:10Z |
| publishDate | 2020-11-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-b3cd6c1417d64d0b9e3bd267543129cd2023-11-20T20:27:28ZengMDPI AGEnergies1996-10732020-11-011322586610.3390/en13225866Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind TurbinesWang-chun Zhang0Hao Jing1Hai-lei Kou2Facility Horticulture Laboratory of University in Shandong, Weifang 262700, ChinaCollege of Engineering, Ocean University of China, Qingdao 266100, ChinaCollege of Engineering, Ocean University of China, Qingdao 266100, ChinaThe interface behavior between a caisson and the surrounding soil plays an important role in the installation of suction caissons as foundations for offshore wind turbines. A series of shear tests were carried out using a modified direct shear apparatus to study the interface shear behavior between sand and concrete. Sand samples with three particle size ranges (0.63–1.25 mm, 1.25–2.5 mm, 2.5–5.0 mm) and concrete plates with different relative roughness were used to explore the influence of the relative roughness parameter (<i>R</i><sub>n</sub>) and mean particle size (<i>D</i><sub>50</sub>) on shear behavior. The responses from the pure sand shear test are also discussed for comparison. Test results show that the higher the relative roughness (<i>R</i><sub>n</sub>), the greater the maximum shear stress (<i>τ</i><sub>max</sub>) appeared. The interface shear stress was weaker than that of the pure sand test. Furthermore, the interface friction angle (<i>φ</i>) of sand–concrete was closely related to the relative roughness of the concrete surface. Under the same conditions, the interface friction angle (<i>φ</i>) increased with relative roughness due to the effect of sand particles breakage and redistribution. By contrast, the effect of the mean particle size (<i>D</i><sub>50</sub>) on the interface friction angle (<i>φ</i>) was less significant. However, for the pure sand shear test, the friction angle (<i>φ</i>′) obtained from the traditional shear test apparently increased with <i>D</i><sub>50</sub>, indicating that the friction angle was more affected by <i>D</i><sub>50</sub> in the pure sand test than in the interface shear test.https://www.mdpi.com/1996-1073/13/22/5866offshore wind turbinesuction caissonrelative roughnessparticle size of sandinterface behavior |
| spellingShingle | Wang-chun Zhang Hao Jing Hai-lei Kou Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines Energies offshore wind turbine suction caisson relative roughness particle size of sand interface behavior |
| title | Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines |
| title_full | Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines |
| title_fullStr | Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines |
| title_full_unstemmed | Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines |
| title_short | Effects of Relative Roughness and Particle Size on the Interface Behavior of Concrete Suction Caisson Foundation for Offshore Wind Turbines |
| title_sort | effects of relative roughness and particle size on the interface behavior of concrete suction caisson foundation for offshore wind turbines |
| topic | offshore wind turbine suction caisson relative roughness particle size of sand interface behavior |
| url | https://www.mdpi.com/1996-1073/13/22/5866 |
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