Predictive 1D and 2D guided-wave propagation in composite plates using the SAFE approach

Abstract

In this paper, a semi-analytical finite element (SAFE) approach is presented to model the guided-wave propagations in composite plates. The theoretical framework is formulated using finite element method (FEM) to describe the material variation along the thickness direction and assuming analytical solutions in the wave propagation direction. As with any finite element approach, the convergence study is first performed to ensure the accuracy of the solution. Then, the dispersive curves are obtained in terms of phase velocity, group velocity, and steering angle. In general, a wave packet in composite plates with anisotropic characteristics does not travel in the same direction as the phase velocity, and the difference is defined as steering angle. Knowledge of these properties in composite plates is important in guided waves based SHM applications. Finally, it is experimentally validated using the scanning laser Doppler vibrometer (SLDV) measurements of guided wave packets generated by a piezoelectric wafer active sensor (PWAS) in a unidirectional carbon fiber reinforced polymer (CFRP) composite plate. It will be shown that the SAFE approach achieves a good agreement with experimental results.