Validity of Identified Modal Parameters based on Rotor-Stop Tests of Offshore Wind Turbines

The increasing energy prices together with the uncertainty about long term sufficiency of fossil fuel resources, confirm the increasing need for reliable alternatives based on renewable energy. Offshore wind power, particularly, has a great potential in providing a large share of the energy demand. The sustainable character of this energy...

Estimation of the Vibration Decrement of an Offshore Wind Turbine Support Structure Caused by its Interaction with Soil

In today’s cutting costs environment in the offshore wind industry, significant achievements can be made with a better assessment of dynamic soil-pile interaction. More knowledge regarding the contribution of the dynamic soil-pile interaction to damping of an offshore wind turbine structure (OWT) could perceptibly reduce the fabrication costs of...

The influence of Mooring Lines on the Damping of Low Frequency Motions of Moored Offshore Structures

For years it has been customary, in the prediction the Low Frequency (LF) dynamic behaviour of moored offshore structures, to assume that the mooring system only influences the restoring force characteristics. The contribution of the mooring system to the total system damping was neglected. Research and model tests in recent years have shown...

Dynamic analysis of Jack-ups

Jack-up offshore structures have a natural period which lies in the high frequency tail of the spectra of North Sea storm waves. This taxi has Significant energy and the jack-up may experience significant dynamic Data have become available from field measurements of the dynamic behaviour of the Maersk Guardian jack-up rig. These data have been...