Damping ratio from surface wave tests

Abstract

This study explores the effectiveness of Continuous Surface Wave System (CSWS) in determining the damping ratio of a decaying surface wave and the different methods of deriving the damping ratio.

Logarithmic Decrement (δ) method and Absorption Coefficient (β) method are used in this study to determine the material damping ratio. The continuous surface wave test is also simulated using a finite element model. Through the finite element model, the methods are found to be effective in estimating damping ratio. Wave amplitudes at both steady state and decaying state are required. It is found that waves are more stable at higher frequency, with lower damping ratio measured.