On the interaction between nonlinear solitary waves and laminated composite beams

Experiments and numerical calculations are performed to study the interaction between nonlinear solitary waves in granular chains and laminated composite beams made of carbon fibre/epoxy (CFRP) or glass fibre/epoxy (GFRP) composites. The experiments were conducted using a vertical array of 21 steel beads contacting a simply-supported composite beam at mid-span. A striker bead was dropped from a given height to initiate the propagation of a single solitary wave in the granular chain, whose interaction with the beam gave rise to the propagation of multiple reflected solitary waves. The developed apparatus allowed measuring the delays and amplitudes of the reflected solitary waves, and the obtained measurements were found in good agreement with numerical predictions based on discrete elements and classical beam theory. It was found that the delay and amplitude ratios of the reflected solitary waves are highly sensitive to the lamina properties, composite layup and thickness of the tested laminate, concluding that the developed apparatus is capable of measuring directional stiffness variations in engineering composites, offering a low-cost and time-efficient alternative to conventional destructive test protocols.