Offshore Wind Turbine Foundations

A special issue of Journal of Marine Science and Engineering (ISSN 2077-1312). This special issue belongs to the section "Marine Energy".

Deadline for manuscript submissions: closed (31 January 2023) | Viewed by 26527

Special Issue Editors

Department of Port, Coastal and Offshore Engineering, Tianjin University, Tianjin 300072, China
Interests: fixed and floating foundations for offshore wind turbines; suction bucket foundation; pile foundation; floating foundation; wet towing; integrated transportation and installation; marine structures; marine operations
Special Issues, Collections and Topics in MDPI journals
1. State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China
2. Research Institute, Dalian University of Technology in Shenzhen, Shenzhen 518057, China
Interests: offshore wind energy; drivetrain dynamics; wave energy; floating wind turbine; hydrodynamics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

There have been tremendous developments in offshore wind energy during the past ten years. As a key component, offshore wind turbine foundation, either bottom-fixed or floating, plays a critical role in the dynamics and stability of the whole system. Therefore, there is a large ambition to develop various kinds of foundation technology. This Special Issue focuses on various foundation design, analysis, model tests, installation, and also economic issues.

Dr. Puyang Zhang
Dr. Wei Shi
Guest Editors

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Keywords

  • Bottom-fixed foundation
  • Floating foundation
  • Numerical analysis
  • Model tests
  • Soil–structure interaction
  • Foundation design and analysis
  • Installation
  • Economic analysis

Published Papers (14 papers)

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Research

20 pages, 13045 KiB  
Article
A Study on the Hydrodynamics and Coupling Effects of the Multibody Floating Photovoltaic (FPV) Concept
by Fan Zhang, Wei Shi and Qingqing Wang
J. Mar. Sci. Eng. 2023, 11(8), 1491; https://doi.org/10.3390/jmse11081491 - 26 Jul 2023
Viewed by 1170
Abstract
Floating photovoltaics (FPVs) have been developed rapidly in the past few years and will gradually become the “third pillar” of the photovoltaic industry. To better understand the performance of FPV floaters, this paper provides an in-depth study on the hydrodynamics of a single [...] Read more.
Floating photovoltaics (FPVs) have been developed rapidly in the past few years and will gradually become the “third pillar” of the photovoltaic industry. To better understand the performance of FPV floaters, this paper provides an in-depth study on the hydrodynamics of a single FPV module and the coupling effects of multiple modules. The results show that a conventional frequency domain approach, which includes both panel and Morison models, may not necessarily provide realistic results. Even after adding an additional damping matrix for the floaters based on empirical values from the oil and gas (O&G) industry, and a free surface damping model between the pontoons, the responses were still not convincing. Therefore, a nonlinear time-domain hydrodynamic solver was introduced. Further studies and comparisons were performed to understand the behavior of the module, and some updated damping coefficients were summarized. Thereafter, a multibody hydrodynamic model was built to check the coupling effects. With the additional damping surface on the gap surface among the modules, some attempts were made to derive reasonable results, when the model test was not available. Preliminary studies of both a scaled-down system (with 9 modules and mooring lines) and a full-scale system (with 90 modules, buoys, and mooring systems) were also investigated, and some initial results were demonstrated. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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16 pages, 12978 KiB  
Article
Study of a Method for Drivability of Monopile in Complex Stratified Soil
by Jie Zhang, Kanmin Shen, Bin Wang, Guangyuan Wen and Sa Li
J. Mar. Sci. Eng. 2023, 11(3), 603; https://doi.org/10.3390/jmse11030603 - 13 Mar 2023
Viewed by 1676
Abstract
At present, there is no commonly used method for predicting soil resistance to the driving (SRD) of monopiles, because all available methods are developed based on an installed offshore pile with a diameter of 2–3 m. In addition, due to the complexity of [...] Read more.
At present, there is no commonly used method for predicting soil resistance to the driving (SRD) of monopiles, because all available methods are developed based on an installed offshore pile with a diameter of 2–3 m. In addition, due to the complexity of soil profiles in situ, the accuracy of methods used is often not stable under different soil conditions. Based on two typical stratified soil conditions of offshore wind farms in the East China Sea, which are clay-interlayered sand and sand-interlayered clay where, according to the pile driving records of the monopiles in sites, the SRD is obtained by back analysis using the method of the wave equation. At the same time, SRD is also calculated using Steven and Alm methods and compared with that of the back analysis. The results show that the SRDs from the Steven and Alm methods are basically consistent with that of the back analysis, but the predicted SRD of the clay layer is higher than that of back analysis, while the predicted SRD of the sand layer is lower. Based on the characteristics of SRD in different soil layers, a modified method for calculating unit friction in clay and the unit end resistance in sand is proposed for stratified soil, and the error between SRD of the proposed method and of the back analysis was approximately 20%. It could be helpful to improve the accuracy of the monopile drivability analysis in stratified soil. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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21 pages, 7838 KiB  
Article
Initial Design of a Novel Barge-Type Floating Offshore Wind Turbine in Shallow Water
by Yiming Zhou, Sensen Feng, Xiaojiang Guo, Feng Tian, Xu Han, Wei Shi and Xin Li
J. Mar. Sci. Eng. 2023, 11(3), 464; https://doi.org/10.3390/jmse11030464 - 21 Feb 2023
Viewed by 1573
Abstract
The studies on floating offshore wind turbines (FOWTs) have been increasing over recent decades due to the growing interest in offshore renewable energy. The present paper proposes a barge platform with four moonpools to support the Technical University of Denmark 10 MW wind [...] Read more.
The studies on floating offshore wind turbines (FOWTs) have been increasing over recent decades due to the growing interest in offshore renewable energy. The present paper proposes a barge platform with four moonpools to support the Technical University of Denmark 10 MW wind turbine for a designed water depth of 60 m. A 4 × 2 mooring system with eight mooring lines is also proposed for the barge platform. The main dimensions of the barge platform are optimally selected with respect to its preliminary hydrodynamic properties and potential financial benefit. The proposed barge-type FOWT is then demonstrated to be aligned with the DNV standard requirements in terms of its intact and damage stability. Furthermore, coupled time-domain simulations are conducted for the proposed barge FOWT with mooring under the selected environmental and operational conditions by using Simo-Riflex-AeroDyn (SRA). Through decay test simulations, the natural periods of the barge-type FOWT are demonstrated to be within the DNV recommended ranges. The proposed mooring system is also benchmarked with the 3 × 3 mooring concept that was used for a 3 MW barge-type FOWT installed in Kitakyushu. The response magnitudes of the barge platform and mooring line tension are similar to both mooring systems, and thus the 4 × 2 mooring system is preferred due to its lower cost. In addition, the proposed barge platform is preliminarily demonstrated to be able to survive for the 50-year extreme environmental conditions under parked wind turbine status, as well as the normal environmental conditions under the operating status. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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15 pages, 6277 KiB  
Article
Theoretical Analysis of Dynamic Response of Pipe Pile with Multi-Defects
by Mingchen Zhong and Kun Meng
J. Mar. Sci. Eng. 2023, 11(1), 83; https://doi.org/10.3390/jmse11010083 - 03 Jan 2023
Cited by 1 | Viewed by 1151
Abstract
A mathematical model for an outer soil, multi-defects pipe pile, and inner soil dynamic interaction system is established to research the influences of multi-defects on the vibration of a pipe pile. The dynamic impedance of the pipe pile is deduced by applying a [...] Read more.
A mathematical model for an outer soil, multi-defects pipe pile, and inner soil dynamic interaction system is established to research the influences of multi-defects on the vibration of a pipe pile. The dynamic impedance of the pipe pile is deduced by applying a Laplace transformation method and an impedance recursive technique. Then, the velocity response at the pile head is further obtained using the inverse Fourier transform method. Moreover, parametric analyses are conducted to research the influences of the type, degree, distribution, length, and depth of multi-defects on the vibration of the pipe pile. The results indicate that the characteristics of multi-defects appear different, with amplitude differences and reflected signal features on the velocity admittance and velocity response curve, respectively. This means that the obtained analytical solutions and relevant results can be used to detect multi-defects of pipe piles using the different appearances of the velocity admittance and velocity response curve, as measured in engineering practice. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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25 pages, 5885 KiB  
Article
Vibration-Resistant Performance Study of a Novel Floating Wind Turbine with Double-Rope Mooring System and Stroke-Limited TMD
by Zhouquan Feng, Yuheng Huang, Xugang Hua, Jinyuan Dai and Haokun Jing
J. Mar. Sci. Eng. 2023, 11(1), 58; https://doi.org/10.3390/jmse11010058 - 01 Jan 2023
Cited by 1 | Viewed by 1360
Abstract
Floating offshore wind turbines (FOWTs) are generally located in the harsh deep-sea environment and are highly susceptible to extreme loads. In order to ensure the normal operation of FOWTs, this article takes the semi-submersible FOWT as an example, proposes a new double-rope mooring [...] Read more.
Floating offshore wind turbines (FOWTs) are generally located in the harsh deep-sea environment and are highly susceptible to extreme loads. In order to ensure the normal operation of FOWTs, this article takes the semi-submersible FOWT as an example, proposes a new double-rope mooring system, and studies the dynamic performance of the FOWT with the double-rope mooring system and its effectiveness in reducing the dynamic response of the wind turbine. At the same time, the tuned mass damper (TMD) is installed in the nacelle of the wind turbine, and the TMD parameters are optimized considering the space limitation of the nacelle by limiting the TMD’s stroke, which further reduces the dynamic response of the FOWT and improves its stability. Numerical simulation and analytical studies show that the new double-rope mooring system can reduce the dynamic response of the wind turbine to a greater extent than the traditional single-rope mooring system. Considering the stroke restriction, the control performance of TMD will be slightly weakened, but it is more in line with the actual engineering requirements. Compared with the original FOWT, the proposed new type of FOWT has better dynamic stability and has the prospect of extending to real engineering applications. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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18 pages, 3638 KiB  
Article
Design and Dynamic Analysis of a Novel Large-Scale Barge-Type Floating Offshore Wind Turbine with Aquaculture Cage
by Yuting Zhai, Haisheng Zhao, Xin Li and Wei Shi
J. Mar. Sci. Eng. 2022, 10(12), 1926; https://doi.org/10.3390/jmse10121926 - 06 Dec 2022
Cited by 3 | Viewed by 1802
Abstract
In this study, a novel large-scale barge-type floating offshore wind turbine with an aquaculture cage (LSBT-FOWT-AC) in a water depth of 100 m is designed through fully coupled analysis using the SESAM tool to support the Technical University of Denmark (DTU) 10 MW [...] Read more.
In this study, a novel large-scale barge-type floating offshore wind turbine with an aquaculture cage (LSBT-FOWT-AC) in a water depth of 100 m is designed through fully coupled analysis using the SESAM tool to support the Technical University of Denmark (DTU) 10 MW wind turbine. The intact stability and natural period of motion of the newly designed LSBT-FOWT-AC are evaluated based on the DNV rules and standards. Then, the dynamic responses of the LSBT-FOWT-AC under various sea conditions are studied. The motion of the LSBT-FOWT-AC platform is considerably affected by waves, and its motion response is within a reasonable range even under the extreme sea conditions of the 100-year return period. By analyzing the results of the out-of-plane bending moment of root of blade 1 (RootMyc1), it can be seen that the rotor frequency (1P) has a visible influence on the wind turbine. Through the analysis of dynamic response statistics of the LSBT-FOWT-AC structure by the single variable method of environmental loads, it is found that wind force exerts the greatest impact on the dynamic response compared to the wave-excitation force and current drag force. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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23 pages, 3951 KiB  
Article
Structural Parametric Optimization of the VolturnUS-S Semi-Submersible Foundation for a 15 MW Floating Offshore Wind Turbine
by Shiqi Liu, Zhenju Chuang, Kai Wang, Xin Li, Xin Chang and Lixun Hou
J. Mar. Sci. Eng. 2022, 10(9), 1181; https://doi.org/10.3390/jmse10091181 - 24 Aug 2022
Cited by 3 | Viewed by 2311
Abstract
The full exploitation of offshore wind resources can essentially satisfy the massive energy demand. The realization and application of ultra-high-power offshore wind turbines are crucial to achieving full use of deep-sea wind energy and reducing the cost of wind power. For the VolturnUS-S [...] Read more.
The full exploitation of offshore wind resources can essentially satisfy the massive energy demand. The realization and application of ultra-high-power offshore wind turbines are crucial to achieving full use of deep-sea wind energy and reducing the cost of wind power. For the VolturnUS-S semi-submersible floating foundation of a 15 megawatt (MW) offshore wind turbine, the effect of structural parameters on hydrodynamic performance was investigated by controlling the variables described in this paper. Accordingly, the floating foundation was optimized and coupled to the 15 MW offshore wind turbine. The dynamic performance of the integrated 15 MW offshore wind turbine was analyzed under different operating conditions, by applying the aero-hydro-servo-elastic coupled method. The results show that for a wave in a 0-degree direction, a 5% increase of column spacing will reduce the peak value of the pitch transfer function by 33.61%, and that a 5% decrease of the outer column diameter will further reduce the peak value by 26.27%. The standard deviation of the time-domain surge responses was reduced by 19.78% for the optimized offshore wind turbine, and the maximum value of the mooring line tension was reduced by 13.55% under normal operating conditions. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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13 pages, 3364 KiB  
Article
Influence of Corrosion Damage on Fatigue Limit Capacities of Offshore Wind Turbine Substructure
by Ying Li, Yu Zhang, Wenhua Wang, Xin Li and Bin Wang
J. Mar. Sci. Eng. 2022, 10(8), 1011; https://doi.org/10.3390/jmse10081011 - 24 Jul 2022
Cited by 3 | Viewed by 1499
Abstract
The decrease in structural capacities under the limit states caused by structural corrosion is a potential hazard for the safety of offshore structures. Considering the influence of corrosion factors, a fatigue analysis of the typical tubular joints of an offshore wind turbine (OWT) [...] Read more.
The decrease in structural capacities under the limit states caused by structural corrosion is a potential hazard for the safety of offshore structures. Considering the influence of corrosion factors, a fatigue analysis of the typical tubular joints of an offshore wind turbine (OWT) substructure under operation and wave loads during the service period was performed. The structural corrosion was equivalent to a two-parameter Weibull distribution in the analysis. According to the Miner linear fatigue accumulation criterion, the accumulated fatigue damage of three different typical tubular joints in the initial stage and at operation periods of 10, 20, and 30 years was calculated. The most critical tubular joint of the studied OWT substructure is located at the connection between the pile foundations and braces. Owing to the increase in structural corrosion during the operation period, a remarkable decrease in the tubular joint fatigue capacities under the operation and wave loads was observed. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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24 pages, 7465 KiB  
Article
Bearing Characteristics of Helical Pile Foundations for Offshore Wind Turbines in Sandy Soil
by Yifeng Lin, Jiandong Xiao, Conghuan Le, Puyang Zhang, Qingshan Chen and Hongyan Ding
J. Mar. Sci. Eng. 2022, 10(7), 889; https://doi.org/10.3390/jmse10070889 - 28 Jun 2022
Cited by 10 | Viewed by 1863
Abstract
Helical pile foundations are a new foundation type for offshore wind power applications with high bearing capacity and good recovery that can be quickly and easily constructed. In this study, the finite element method was used to simulate the bearing characteristics of helical [...] Read more.
Helical pile foundations are a new foundation type for offshore wind power applications with high bearing capacity and good recovery that can be quickly and easily constructed. In this study, the finite element method was used to simulate the bearing characteristics of helical pile foundations after installation. For simulations, a blade, deeply buried in a single layer of sand, was selected. Through numerical simulations, the vertical bearing characteristics of a single helical screw pile and an ordinary pile without blades were compared, and the compression and uplift characteristics of the helical pile were revealed. In addition, the effects of pitch, blade diameter, inclination angle, number of blades, and blade spacing on the bearing characteristics of a single helical pile were analyzed. The results show that the single helical pile has the highest bearing capacity and bearing efficiency when the pitch is 0.02 times the blade buried depth, the blade diameter is 2.5 times the pile diameter, the multi-blade spacing is more than two times the blade diameter, and the number of blades is less than or equal to three. However, compared with the straight pile, the vertical bearing capacity of the single inclined helical pile did not improve significantly. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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21 pages, 11526 KiB  
Article
Dynamic Response Analysis of Offshore Converter Station Based on Vector Form Intrinsic Finite Element (VFIFE) Method
by Zhenzhou Sun, Yang Yu, Huakun Wang, Shanshan Huang and Jiefeng Chen
J. Mar. Sci. Eng. 2022, 10(6), 749; https://doi.org/10.3390/jmse10060749 - 29 May 2022
Cited by 1 | Viewed by 1804
Abstract
This study aims at proposing a simulation method for an offshore converter station platform (OCS) under dynamic loading. A user-defined in-house FORTRAN code was developed based on the Vector Form Intrinsic Finite Element (VFIFE) method, and the numerical model was validated by test [...] Read more.
This study aims at proposing a simulation method for an offshore converter station platform (OCS) under dynamic loading. A user-defined in-house FORTRAN code was developed based on the Vector Form Intrinsic Finite Element (VFIFE) method, and the numerical model was validated by test data. After model validation, the dynamic behavior of the OCS was carefully studied and the effect of different loading conditions, including seismic, hydrodynamic and wind load, on the dynamic behavior of OCS was investigated. The time history of the structural response was obtained, and the relationship between the structural peak response and the peak value of the seismic load was also shown. It indicated that water damping accelerates energy consumption, while the effect of hydrodynamic and wind load has little influence on the cases studied in this work. Generally, the peak response increases almost linearly with the increase in the peak acceleration of the ground, and the seismic propagating direction has a great impact. In addition, both a whipping effect and stretching-squeezing effect were observed, and the vertical acceleration response of the valve hall deck is much higher than other structures, which is caused by the relatively lower local rigidity of the large-span structure and the inertia force caused by the valve tower. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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20 pages, 17165 KiB  
Article
Mechanical Characteristics of Prestressed Concrete Curved Transition Section of Composite Bucket Foundations for Offshore Wind Turbines
by Puyang Zhang, Yunlong Xu, Jiandong Xiao, Conghuan Le and Hongyan Ding
J. Mar. Sci. Eng. 2022, 10(4), 473; https://doi.org/10.3390/jmse10040473 - 28 Mar 2022
Cited by 1 | Viewed by 1754
Abstract
The composite bucket foundation (CBF) consists of a concrete curved transition section, a concrete beam-slab system, and a suction caisson and is increasingly used as the foundation for offshore wind turbines. The curved transition section transmits the upper load from the tower to [...] Read more.
The composite bucket foundation (CBF) consists of a concrete curved transition section, a concrete beam-slab system, and a suction caisson and is increasingly used as the foundation for offshore wind turbines. The curved transition section transmits the upper load from the tower to the foundation, and its force and transmission characteristics are related to the safety of the entire wind turbine structure. The arced transition section has the characteristics of complex geometry, load conditions, and large curvature. It is difficult to determine its bearing characteristics and force transmission system. In this paper, the boundary conditions and loading device of the CBF model test are designed, and three 1:20 arced transition section model specimens are made. The mechanical characteristic experiments of CBF are used to analyze the failure process, failure characteristics, and seismic performance of the structure. Results show that the cracking effect of the arced transition section after prestressing is obviously better than that of a reinforced concrete arced transition section structure. The arced transition section specimens equipped with prestressed tendons can increase the structural cracking load ratio by about 35% for reinforced concrete members. The energy dissipation capacity of the specimens has been significantly improved, and the material properties can be fully utilized. The failure mode of the arced transition section structure under horizontal reciprocating load shows the characteristics of bending and shear failure. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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16 pages, 21388 KiB  
Article
Investigation on a Large-Scale Braceless-TLP Floating Offshore Wind Turbine at Intermediate Water Depth
by Yiming Zhou, Yajun Ren, Wei Shi and Xin Li
J. Mar. Sci. Eng. 2022, 10(2), 302; https://doi.org/10.3390/jmse10020302 - 21 Feb 2022
Cited by 2 | Viewed by 3360
Abstract
Tension leg platform (TLP) is a cost-effective and high-performance support structure for floating offshore wind turbine (FOWT) because of its small responses in heave, pitch, and roll with the constraint of the tendons. China, as the largest market of offshore wind energy, has [...] Read more.
Tension leg platform (TLP) is a cost-effective and high-performance support structure for floating offshore wind turbine (FOWT) because of its small responses in heave, pitch, and roll with the constraint of the tendons. China, as the largest market of offshore wind energy, has shown a demand for developing reliable, viable floating platform support structures, especially aiming at the intermediate water depth. The present paper described a newly proposed 10-MW Braceless-TLP FOWT designed for a moderate water depth of 60 m. The numerical simulations of the FOWT are carried out using the coupled aero-hydro-servo-elastic-mooring calculation tool FAST. The measured wind and wave data of the target site close to the Fujian Province of China were used to evaluate the performance of the FOWT under the 100-, 50-, 5-, and 2-year-return stochastic weather conditions. The natural periods of the platform in surge, sway, heave, pitch, roll, and yaw were found to be within the range recommended by the design standard DNV-RP-0286 Coupled Analysis of Floating Wind Turbines. The largest surge of the water depth ratio among all the load cases was 15%, which was smaller than the admissible ratio of 23%. The tower top displacements remained between −1 m and 1 m, which were at a similar order to those of a 10-MW monopile-supported offshore wind turbine. The six tendons remained tensioned during the simulation, even under the operational and extreme (parked) environmental conditions. The Braceless-TLP FOWT showed an overall satisfying performance in terms of the structural stability and illustrates the feasibility of this type of FOWT at such a moderate water depth. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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16 pages, 7408 KiB  
Article
Bearing Characteristics of Tripod Bucket Jacket Foundation for Offshore Wind Turbines in Sand under Monotonic Loads
by Guilan Wang, Yi Gan, Conghuan Le, Ruiyang Yan and Xueyang Hu
J. Mar. Sci. Eng. 2022, 10(2), 199; https://doi.org/10.3390/jmse10020199 - 01 Feb 2022
Cited by 4 | Viewed by 1706
Abstract
Tripod bucket jacket foundation is an alternative foundation solution for deep-sea wind farms. This paper analyzes and compares the bearing characteristics of two tripod bucket jacket foundations with different height-diameter ratios, the tripod suction pile jacket foundation (TSPJF) and tripod bucket jacket foundation [...] Read more.
Tripod bucket jacket foundation is an alternative foundation solution for deep-sea wind farms. This paper analyzes and compares the bearing characteristics of two tripod bucket jacket foundations with different height-diameter ratios, the tripod suction pile jacket foundation (TSPJF) and tripod bucket jacket foundation (TBJF), under different monotonic loads. The bearing modes of the two foundations under the vertical loads are different. The ultimate vertical load is mainly borne by the inside frictional resistance for the TSPJF, while it is mainly borne by the lid resistance for the TBJF. The foundations will take place translation and rotation under horizontal load. Under the positive x-axis loading, the vertical resistance of the TSPJF and TBJF is mainly composed of the soil resistance on the 1# bucket lid, the inside and outside frictional resistance. Under the negative x-axis loading condition, the vertical resistance is mainly composed of the inside and outside frictional resistance of buckets. The ultimate moment capacities of the TSPJF and TBJF in loading of the single bucket in compression is significantly larger than that in loading of the single bucket in tension. The failure mode of the TSPJF and TBJF in loading of the single bucket in tension is the pull-out failure of the bucket in tension. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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20 pages, 8305 KiB  
Article
Floating Behavior of a Composite Bucket Foundation under the Combined Action of Wind and Waves
by Xing Zhao, Puyang Zhang, Conghuan Le and Hongyan Ding
J. Mar. Sci. Eng. 2022, 10(2), 147; https://doi.org/10.3390/jmse10020147 - 23 Jan 2022
Viewed by 1875
Abstract
In this study, a composite bucket foundation (CBF) was investigated by taking into account the reflection and refraction effects of waves. A numerical model for the motion responses of the structure under different wave heights and wave periods was built based on the [...] Read more.
In this study, a composite bucket foundation (CBF) was investigated by taking into account the reflection and refraction effects of waves. A numerical model for the motion responses of the structure under different wave heights and wave periods was built based on the 3D potential flow theory. The model was verified against the test results for analyzing the stability and seakeeping performance of the foundation under the action of waves. Under the combined action of wind and waves, the possible scenarios of floating under wind and waves of different scales and directions were simulated, and the mooring force and motion response peaks and laws of the structure were established, aiming to improve the safety of composite bucket foundation transport and provide technical support for floating construction. Full article
(This article belongs to the Special Issue Offshore Wind Turbine Foundations)
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