Basic research of applying the guided wave to the foundation piles of offshore wind turbines

As offshore wind turbines are located in the sea, column foundation piles under the surface of the seabed which are affected by vibration, ocean power (waves and currents), earthquakes and other external forces, might affect the firmness between the foundation piles and the seabed. This will in turn affect the stability of the offshore wind turbine. Therefore, regular maintenance of the piles is very important. Since the guided wave method has long-range energy transmission and does not lose energy easily, when we use pipeline to transmit, the pipeline detection range would be greater. In this study, we will be using the ultrasonic transducer to make the guided wave method so as to assess the characteristics of the column on the surface. After which, we will start to plan, design and develop testing equipment and methods which are safe and effective in order to conduct regular assessments of the piles’ foundation. In this study, the foundation piles will be replaced by a single steel pipe as a model represent. PCdisp will be used to draw the dispersion curve to find the suitable mode and angle. After setting up the ultrasonic transducer and adjusting it to the best settings, we will explore the firmness between the foundation piles, the seabed and the corrosion of the surface. We will then be able to design a coated experiment to simulate the coated situation, and also an artificial corrosion experiment to simulate the corrosion. By applying the guided wave method, we will analyze and judge the structural condition of the surface so as to achieve the purpose of this study.