本文探討兩層及三層奈米碳管的簡支梁受衝擊載重後於觀測點的波傳行為，以Timoshenko梁理論為基礎分析多層奈米碳管，層與層間考慮凡德瓦力，並以Winkler彈簧模擬土壤及周圍介質的交互作用。
分析方法上，以射線法理論解搭配Durbin逆數值轉換求得雙層及三層奈米碳管的波傳暫態反應。並探討微小因子對多層奈米碳管的影響，由結果可知當加入微小因子後其暫態反應會變得平滑，並且使外力施加後奈米碳管的觀測點上即刻產生反應。此外，本文亦探討奈米碳管的螺旋性與半徑對多層奈米碳管暫態反應的結果，我們發現多層奈米碳管的半徑為影響暫態反應的主要因素，而非螺旋性。最後，本文亦以頻散圖配合模態分析奈米碳管的穩態行為，結果顯示雙層奈米碳管共有四組不同振態，而三層奈米碳管共有六組振態。隨著微小因子的不同，頻散圖亦產生很大的差異。

In this study, wave propagation behavior multi-walled carbon nanotubes is analyzed through nonlocal elasticity and Timoshenko beam theory. Van der Waals force is considered between layers, and the interaction between soil and surrounding medium is simulated by Winkler foundation. In terms of analytical methods, the wave propagation transient responses of double-walled and triple-walled carbon nanotubes are obtained by the ray method and the Durbin inverse numerical transformation. The effect of nonlocal parameter on multi-walled carbon nanotubes is also discussed. The results show that as the increment of nonlocal parameter, the transient responses become smoother, and the observation point of carbon nanotubes will react immediately after the external force is applied. In addition, we also discusses the effect of chirality and radius of the carbon nanotubes. We found that the radius of the multi-walled carbon nanotubes is the main factor for affecting the transient response, not the helicity. Finally, the steady-state behavior of carbon nanotubes is also analyzed with dispersion diagrams and modes. The results show that there are four groups of different vibration states for double-walled carbon nanotubes, while there are six groups for triple-walled carbon nanotubes. Dispersion plots also vary greatly with small factors.

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