Contactless control of suspended loads for offshore installations: Proof of concept using magnetic interaction

Current offshore wind turbine installation and positioning methods require mechanical equipment attached on the lifted components and human intervention. The present paper studies the development of a contactless motion compensation technique by investigating a magnetically controlled pendulum. The technique involves the interaction of a...

Magnetic stray field measurements to identify and localise impact-induced plastic deformation in a steel structure

To study the irreversible changes in the magnetic stray field surrounding a steel structure caused by impact-induced elastic and plastic deformations, a steel cylinder was repeatedly subjected to axial impacts of various magnitudes. Due to impacts that induce elastic deformation, the measured magnetic stray field of the structure converges to...

Magnetomechanical response of a steel monopile during impact pile driving

This paper reports on a measurement campaign in which the magnetomechanical response of a steel monopile is recorded during installation with a hydraulic impact hammer. By comparing impact-induced changes in the magnetic stray field of the structure to the measured strain, this effect is analysed for the first time under dynamic loading...

A non-collocated method to quantify plastic deformation caused by impact pile driving

The use of bolted connections between the tower and a support structure of an offshore wind turbine has created the need for a method to detect whether a monopile foundation plastically deforms during the installation procedure. Small permanent deformations are undesirable, not only because they can accelerate fatigue of the structure; but...

Plasticity detection and quantification in monopile support structures due to axial impact loading

Recent developments in the construction of offshore wind turbines have created the need for a method to detect whether a monopile foundation is plastically deformed during the installation procedure. Since measurements at the pile head are difficult to perform, a method based on measurements at a certain distance below the pile head is...