Partial Safety Factor of Offshore Wind Turbine Pile Foundation in West-South Mainland Sea

In this paper, the nonlinear corrosion model under the combined action of the anticorrosion system and corrosive environment is chosen as the mathematical model of homogeneous corrosion of steel pipe pile foundation for the offshore wind turbine. Based on the mathematical model, a three-dimensional finite element model was established for the steel pipe pile foundation of the offshore wind turbine. And the homogeneous corrosion action of the steel pipe piles was calculated, and the reduction rules of the strength and stability of the steel pipe piles for wind turbines under different corrosion patterns are analyzed. According to the calculation results, the mathematical model can be used in the analysis of corrosion for steel pipe pile in the wind turbine. Under the normal operation conditions, the reduction rules of the strength and stability of the steel pipe piles contain three stages: no influence stage, negative exponential decrease stage, and stable stage. But under the extreme load conditions, the effect of corrosion is enormous for the strength and stability of the steel pipe pile.

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Improving Pile Foundation Models for use in Bottom-fixed Offshore Wind Turbine Applications

Energy Procedia ◽

10.1016/j.egypro.2012.06.119 ◽

2012 ◽

Vol 24 ◽

pp. 363-370 ◽

Cited By ~ 7

Author(s):

Eric Van Buren ◽

Michael Muskulus

Keyword(s):

Wind Turbine ◽

Pile Foundation ◽

Offshore Wind ◽

Offshore Wind Turbine

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Design and Structural Analysis of Mono Pile Foundation for Offshore Wind Turbines

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 2 ◽

10.1115/omae2010-20750 ◽

2010 ◽

Author(s):

Jianhua Zhang ◽

Zhenqing Wang ◽

Liang Zhang ◽

Ke Sun ◽

Jun Hao

Keyword(s):

Finite Element ◽

Wind Turbine ◽

Wind Turbines ◽

Pile Foundation ◽

Dynamic Responses ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Bohai Bay ◽

Time Dynamic ◽

Stress And Deformation

Offshore wind energy offers a huge potential for expansion of renewable energy in the world. However, placement of wind turbines in harsh offshore environments is an engineering challenge, which requires development of suitable foundation designs. This paper shows different foundation types which are decided by different cases of the seabed. The mono pile foundation for 1.5MW offshore wind turbine is designed for Bohai Bay in China considering the soil and seabed condition. A three dimensional (3D) finite element model of mono pile is established to analyze horizontal ultimate bearing capacity, stress and deformation under lateral loads. Through the modal analysis, the natural frequencies of the mono-pile are given. Results show that the designed mono pile can effectively preclude resonance with the wind turbine. Dynamic responses under wave and seismic loads are analyzed by transient analysis method. And at same time, dynamic amplification factors of stress and deformation are studied. The paper reaches the conclusion that the dynamic effect must be attached importance in the design. Moreover, based on the theory of stability, the simplified method to assess the ultimate buckling moment of the mono pile is put forward. Comparisons are also made with results calculated by codified rules of DNV and ABS and Finite Element Method. Besides, fatigue analysis is carried out according the codified rules of API. The numerical results demonstrate that the design of mono pile is reasonable and reliable. The research results can provide the reference for practical engineering in China.

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Horizontal Loading Performance of Offshore Wind Turbine Pile Foundation Based on DPP-BOTDA

Applied Sciences ◽

10.3390/app10020492 ◽

2020 ◽

Vol 10 (2) ◽

pp. 492 ◽

Cited By ~ 1

Author(s):

Zhaohui Zhang ◽

Peng Guan ◽

Jinlong Xu ◽

Benzhang Wang ◽

Hui Li ◽

...

Keyword(s):

Bearing Capacity ◽

Wind Turbine ◽

Wind Power ◽

Spatial Resolution ◽

Pile Foundation ◽

Offshore Wind ◽

Offshore Wind Turbine ◽

Horizontal Load ◽

Strain Data ◽

Distributed Strain

Offshore wind power is becoming attractive in the wind-power field. With the rapid development of wind-power technology, high-power wind turbines have been implemented in practice. However, the increase in the length of the wind turbine blade causes the pile foundation to withstand a prone overturning moment. For overcoming the problems of traditional sensing technology and meeting the monitoring requirements of pile foundations, a 20 cm spatial resolution differential pulse pair Brillouin optical time-domain analysis (DPP-BOTDA) technique is used to measure a 69 m long offshore wind turbine pile under horizontal loading. From the distributed strain data collected in the test, the maximum stress location of the long pile under the horizontal load can be obtained. By analyzing the load and maximum strain (F-εmax) curve, the horizontal bearing capacity of the pile foundation can exceed 900 kN, which is the maximum horizontal load of the design. The distributed displacement calculation method based on distributed strain data is proposed, according to the force characteristics of steel pipe piles. By comparing the calculated displacement data with the measured data by the dial indicators, the mean absolute percentage error (MAPE) value is only 0.03548. Results show that the 20 cm spatial resolution DPP-BOTDA technology is very suitable for the bearing capacity test of offshore wind turbine steel pipe pile foundations.

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