Study on the propagation of stress waves in natural fibre composite strips

The propagation of Lamb waves within the structure of natural fibre reinforced composite strips is investigated using a semi-analytical solution and a time domain spectral finite element numerical method. The need to monitor the structural health of natural fibre reinforced composites is becoming greater, as these sustainable composites are being increasingly used in various industrial applications in automotive and marine structures. Three different types of flax fibre composites were studied and the fundamental wave modes were excited on the structure. Both methods under consideration were able to capture the symmetric and anti-symmetric wave modes for all the material configurations. Especially the complex nature of a hybrid flax/glass fibre composite is studied and results are very promising for future damage investigation. Further to this, an attempt was made to excite the hybrid strip at higher frequency and the study revealed the potential to capture all the existing wave modes.