Damping Estimation using Operational Modal Analysis
نویسندگان
چکیده
It has been observed that even though modal frequencies are well estimated using Operational Modal Analysis (OMA) techniques, damping estimation is not as accurate. The opinions on this aspect of OMA have been widely varying and no consensus or definite answers are available. In this paper the OMA procedure, data processing and modal parameter estimation, is studied with respect to proper damping estimation. It is shown how the use of certain signal processing techniques like cyclic averaging can help in more accurate estimation of damping. The paper also analyzes the effect of correlated forces on the parameter estimation using OMA.
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