FEM-Based Preliminary Design of a Vibration Monitoring System in the Context of Decommissioned and Reinstalled Wind Towers

In the context of steel structures, the structural longevity of wind turbines amidst aging poses a significant challenge, underscoring the need for sustainable solutions to enhance their lifespan and enable efficient reuse in line with a circular economy. However, the adoption of circular solutions, based on the decommissioning and re-installation of older towers requires monitoring solutions that could guarantee the structural health and safety management of the structure. This study proposes an application of Finite Element Method (FEM) aimed at producing a first guess on the potentially-suitable technical and installation requirements for a vibration monitoring system to be operated for a steel wind turbine. The research is applied to a wind tower, being originally 65mhigh, which was disassembled and reassembled at a reduced height of 45 m to increase its service lifetime, adopting a circular economy approach. The described application is part of a method, consisting in a continuous integration and mutual optimization of the monitoring system and its digital model counterpart. Such an integration avoids the parallelization of initial modelling and monitoring for validation, while it goes beyond the step of matching the model and the experimental data, with the aim of producing a tuned FEM. The application of the proposed approach to steel structures in the strategic industrial sector of renewable energy production proved again to be effective, as in the previous context of cultural heritage structures, implying the possibility of expanding the use of this method to different context, such as structural health monitoring systems, structural safety, critical structures and infrastructures monitoring and management, and long-term monitoring for structures with a prolonged service lifetime, contributing to an increased adoption of sustainable and circular solution.