Calculation of the response of a composite plate to localized dynamic surface loads using a new wave number integral method

This study is motivated by the need for an efficient and accurate tool to analyze the wave field produced by localized dynamic sources on the surface or the interior of isotropic plates and anisotropic composite laminates. A semi-analytical method based on the wave number integral representation of the elastodynamic field is described that reduces the overall computational effort significantly over other available methods. This method is used to calculate the guided wave field produced in a thin unidirectional graphite/epoxy composite laminate by a dynamic surface point load. The results are compared with those obtained from a finite element analysis, showing excellent agreement, except for minor differences at higher frequencies. A recently discovered feature of the calculated surface motion, namely, a spatially periodic "phase reversal " of the main pulse with propagation distance, is observed in both cases. The present work is expected to be helpful in developing impact damage monitoring systems in defect-critical structural components through real time analysis of acoustic emission wave forms.