Damping Estimation of Structure using Operational Modal Analysis

Kurzfassung

The damping property of a structure plays an essential role during dynamic analysis, especially at the natural frequencies, where it defines the amplification of the structure’s response. The damping property of a structure does not relate to a unique physical phenomenon, which makes it difficult to assess accurately. The current conventional methods for estimating damping properties rely on industry-standard values and controlled environment vibration tests, which are conservative and fail to represent the real boundary conditions associated with the running or operational system. This thesis proposes a novel Brute-Force method based on Operational Modal Analysis (OMA) which estimates precise damping values for structures under operational conditions. The BruteForce OMA technique is developed, such that it provides precise and reliable damping estimations with limited sample data and shorter run time, which will help provide deeper insights into the dynamic properties and behaviour of structures. The Brute-Force method has been tested against synthetic signals as well as real-life signals, and the obtained results from these tests illustrate damping value estimates with reasonable error, these errors are consistent and repeated for specific frequencies and damping values. These error estimates help us to predict the errors associated with the damping estimates. This suggests its potential for application across different industries and promotes future research workand development in dynamic analysis of structures. This thesis proposes a unique method which gives precise damping estimates with reasonable error and yields valuable insights into optimizing the design of structures for performance and safety across various industries. This method is still not fully fine-tuned for complex applications. It is therefore imperative that future research utilizing this method refines the technique and extends its use to a wider range of structural systems to make the method more effective. The improvement of this method will pave the way for future research into dynamic behaviours of structures that have not yet been explored.