Abstract Summary
At present, the fatigue-life design of Offshore Wind Turbines (OWTs) is based on design assumptions accounting for significant uncertainties both on loading and fatigue-resistance of different vulnerable structural details. Monitoring of strain histories can potentially have a significant positive impact when estimating the remaining life of Offshore Wind Turbines (OWTs), as the uncertainties are reduced. However, strain-based monitoring approaches present the important drawbacks, the first of them being that only instrumented locations can be assessed and the second that there tend to be accessibility issues associated with the installation process. In this paper, the initial results of a novel methodology developed to estimate strain time histories are presented. The underlying idea of such approach is to combine an updated FE model with the vibration response histories acquired with only a few sensors to estimate the strain histories at any location of an OWT.
