ABSTRACT

Wind turbines can be considered as an essential element to develop alternative and sustainable energy sources. These structures are highly flexible and are subjected to intense wind loading over their lifetime, resulting in significant movement of the exposed structure as well as cyclic degradation of the soil stiffness arising from the excessively large number of stress cycles inherent in the turbine system. In this paper, we focus on onshore piled wind turbine foundations and the mechanics of the soil structure interaction with respect to the vibration effects on the foundation system. Various items that the designer should be aware of with regards to pile layout and frequency characteristics of the site are discussed and the limitations and assumptions of simplified methods of analysis (e.g. lumped parameter model) are examined.