Modelling of the interaction between nonlinear solitary waves and composite beams

We examine numerically the interaction between solitary waves in lightly pre-compressed granular chains and laminated composite beams. A discrete element (DE) model is developed to simulate, with low computational effort, the propagation of solitary waves in a linear array of spherical particles as well as their interaction with a transversely isotropic composite beam. The derived equations allow identifying the governing dimensionless parameters and their effects on the delays and amplitudes of the reflected solitary waves are studied. It is found that the formation of reflected solitary waves is highly sensitive to the beam's geometry as well as to the elastic properties and layup of the laminate. For a beam of given dimensions, the delays and amplitudes of the reflected solitary waves are strongly affected by the flexural stiffness of the composite beam. The DE predictions are compared to those obtained from a more detailed hybrid discrete/finite element model and good agreement is reported for a wide range input parameters. The results of this study support the idea of developing a low-cost solitary wave-based diagnostic scheme for non-destructive evaluation of basic elastic properties of engineering composites.