MCGF piling vibrations: A numerical assessment of the structural dynamics of a Motion-Compensated Gripper Frame during pile driving of XXL monopiles

The increase of demand for offshore wind energy resulted in an increase of larger wind turbines. These turbines are often placed on top of a monopile (MP) substructure. The conventional method for installing these MPs uses a jack-up vessel. However, due to the local bathymetry and soil conditions. This method has its drawbacks, such as...

Jacking system control strategies during the seabed penetration phase of a wind turbine installation vessel

Wind turbine installation vessels (WTIVs) are ships that are specifically designed to install offshore wind turbines. These WTIVs have four or six large truss-like legs that are lowered towards the seabed by means of jacking systems. These jacking systems are regulated by control systems to ensure the leg is lowered with a constant velocity...

Motion compensated offshore knuckle boom crane: A mechanical feasibility study

To overcome the problem of wave-induced vessel motions on the crane tip, technologies have been developed to compensate for these motions. Most vessels nowadays, are equipped with dynamic positioning systems, these systems reduce the yaw, surge and sway movement of the vessel. This leaves, the motions roll, pitch and heave uncompensated. To...

Design and fatigue assessment of the hybrid monopile connection details using finite element analysis

The hybrid monopile is a substructure concept for offshore wind turbines initially designed and developed by Fistuca B.V. This Thesis is about the initial concept design of the connection details in the hybrid monopile. Several concept connections are designed. The best concept is selected and thereafter assessed on the ultimate limit state,...