Damping Estimation of Friction Systems in Random Vibrations

Friction is one of the most efficient and economical mechanisms to reduce vibrations in structural mechanics. However, the estimation of the equivalent linear damping of the friction damped systems in experimental modal analysis and operational modal analysis can be adversely affected by several assumptions regarding the definition of the linear damping and the identification methods or may be lacking a meaningful interpretation of the damping. Along these lines, this project focuses on assessing the potential to estimate efficiently the equivalent linear damping of friction systems in random vibrations with the use of one novel method and two existing ones, modified, though, appropriately. Results of numerical simulations using the three procedures enabled their preliminary comparative assessment in terms of the related damping estimation potential. Indications from the current study showed that two of the methods estimate efficiently the equivalent linear damping, however, the equivalent linear damping seems to depend on the definition of the equivalence. Nonetheless, it seems that the variation of the equivalent linear damping estimates based on the three aforementioned methods becomes less significant when compared to their actual influence on the linear response.