Sensitivity of Hilbert Magnitude and Phase to Structural Damage

This paper discusses a new signal-processing tool involving the use of empirical mode decomposition and its application to health monitoring of structures. Empirical mode decomposition is a time series analysis method that extracts a custom set of basis sets to describe the vibratory response of a system. In conjunction with the Hilbert Transform, the empirical mode decomposition method provides some unique information about the nature of the vibratory response. In this paper, the Hilbert phase for discrete one-dimensional structural elements is compared to the phase obtained from the use of dereverberated wave mechanics. Simulation results indicate that the Hilbert phase is proportional to mass and stiffness properties between two successive degrees of freedom. Hence, the Hilbert phase can be used to infer, locate and possibly quantify the amount of damage in a structure.

Duke Scholars

Author Liming Salvino Civil and Environmental Engineering