Longitudinal wave propagation. Part I—Comparison of rod theories

The paper introduces new four spectral elements for analysis of longitudinal wave propagation in structures. The developed elements are based on the elementary, Love, Mindlin–Herrmann and three-mode theories. Certain differences in wave propagation behaviour are observed for the analysed models. For lower excitation frequencies the results obtained for all models are similar and from a practical point of view the spectral element based on the Love theory is adequate. For high frequency excitation these differences are considerable and only the Mindlin–Herrmann or three-mode models give correct results.