Guided waves in a Timoshenko beam with a bonded composite patch: Frequency domain spectral element modeling and analysis

摘要

Simulation of ultrasonic guided waves in a beam-type structure with a bonded composite patch repair requires a proven modeling and analysis technique that can provide accurate dynamic solutions at a high frequency range. We developed a spectral element model for a metallic beam with a bonded composite patch by using the variational method. To that end, the governing equations of motion are derived by adopting Timoshenko beam theory for the transverse bending motion, and Mindlin-Herrmann rod theory for the longitudinal motion of the composite patched beam to take into account the effects of lateral contraction in the thickness direction. The high accuracy of the spectral element model is then evaluated by comparison with the solutions obtained by the conventional finite element method (FEM) and by the commercial finite element (FE) analysis package ANSYS. By using the spectral element model, the effects of the composite patch on the characteristics of guided waves are numerically investigated. In addition, the effects of debonding are also numerically investigated with respect to monitoring the integrity of the bonded composite patch repair.