Geotechnical Design Considerations for Onshore Wind Turbine Shallow Foundations

With renewable energy and wind energy in particular becoming mainstream means of energy production, the reliability aspect of wind turbines and their sub-assemblies has become a topic of interest for owners and manufacturers of wind turbines. Operation and Maintenance (O&M) costs account for more than 25% of total costs of onshore wind projects and these costs are even higher for offshore installations. Effective management of O&M costs depends on accurate failure prediction for turbine sub-assemblies. There are numerous models that predict failure times and O&M costs of wind farms. All these models have inputs in the form of reliability parameters. These parameters are usually generated by researchers using field failure data. There are several databases that report the failure data of operating wind turbines and researches use these failure data to generate the reliability parameters through various methods of statistical analysis. However, in order to perform the statistical analysis or use the results of the analysis, one must understand the underlying assumptions of the database along with information about the wind turbine population in the database such as their power rating, age, etc. In this work, we analyze the relevant assumptions and discuss what information is required from a database in order to improve the statistical analysis on wind turbines’ failure data.

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Steel hybrid onshore wind towers installed with minimal effort: Development of lifting process

Wind Engineering ◽

10.1177/0309524x18777331 ◽

2018 ◽

Vol 42 (4) ◽

pp. 335-352 ◽

Cited By ~ 4

Author(s):

Mohammad Reza Shah Mohammadi ◽

Carl Richter ◽

Daniel Pak ◽

Carlos Rebelo ◽

Markus Feldmann

Keyword(s):

Wind Turbine ◽

Wind Turbines ◽

Lattice Structure ◽

Cost Component ◽

Onshore Wind ◽

Supporting Structure ◽

Element Simulation ◽

Connection Component ◽

Minimal Effort ◽

Relevant Cost

The total costs per produced kilowatt-hour for wind turbines depend significantly on the investment costs. Thereby, the tower is a relevant cost component, which depends on the chosen supporting structure, the material, and especially on the erection process. Here, an innovative erection process is presented in order to minimize the wind turbine installation, which leads to excluding the extra tall cranes for installing the wind turbines with hub heights over 180 m. In order to propose the innovative erection process, a new hybrid lattice/tubular supporting structure for the onshore wind turbines is designed. The connection component between the tubular part and lattice structure is proposed considering the support functionality for the new erection process. Furthermore, the building steps of the complete erection process are explained. The operational and the lifting loads on wind turbine supporting structure are estimated, and consequently, the erection process stages were analyzed. Finally, the finite element simulation are performed to specify the critical stresses in subcomponents of the supporting structure in each lifting stage and to show the feasibility of the erection process. Moreover, the most critical points and the stages are investigated and stress level in the supporting structure components is computed.

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Seismic Analysis of Onshore Wind Turbine Including Soil-Structure Interaction Effects

Seismic Design of Industrial Facilities ◽

10.1007/978-3-658-02810-7_43 ◽

2013 ◽

pp. 511-522 ◽

Cited By ~ 3

Author(s):

Francesca Taddei ◽

Konstantin Meskouris

Keyword(s):

Wind Turbine ◽

Soil Structure ◽

Seismic Analysis ◽

Interaction Effects ◽

Soil Structure Interaction ◽

Onshore Wind ◽

Structure Interaction

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Comparative Analysis of Kazakhstani and European Approaches for the Design of Shallow Foundations

Applied Sciences ◽

10.3390/app10082920 ◽

2020 ◽

Vol 10 (8) ◽

pp. 2920

Author(s):

Assel Shaldykova ◽

Sung-Woo Moon ◽

Jong Kim ◽

Deuckhang Lee ◽

Taeseo Ku ◽

...

Keyword(s):

Bearing Capacity ◽

Summation Method ◽

Shallow Foundations ◽

Shallow Foundation ◽

Design Procedures ◽

Geological Conditions ◽

Elastic Settlement ◽

Geotechnical Design ◽

The Difference ◽

Design Calculations

The design of shallow foundations is performed in accordance with different building regulations depending on geotechnical and geological conditions. This paper involves the design calculations applying Kazakhstani and European approaches. The design of shallow foundations in Nur-Sultan city in Kazakhstan was implemented by the calculation of bearing capacity and elastic settlement in accordance with the design procedures provided in SP RK 5.01-102-2013: Foundations of buildings and structures, and Eurocode 7: Geotechnical design. The calculated results of bearing capacity and elastic settlement for two types of shallow foundations, such as pad foundation and strip foundation, adhering to Kazakhstani and European approaches are relatively comparable. However, the European approach provided higher values of bearing capacity and elastic settlement for the designed shallow foundation compared to the Kazakhstani approach. The difference in the results is explained by the application of different values of partial factors of safety for the determination of bearing capacity and different methods for the calculation of the elastic settlement of shallow foundations (i.e., elasticity theory and layer summation method).

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