本文之研究目的主要為探討Top-hat型中空薄管元件受到軸向衝擊下之動態行為模式之研究。中空薄壁管元件常見於各種結構體中，例如火車結構、飛機結構及汽車車體結構的潰縮盒等等。當管件結構受軸向衝擊時是否有足夠的強度或吸收撞擊的能量為一個重要的研究議題。因此本文藉由了解top-hat型中空薄壁管元件在軸向衝擊下的動態行為模式，並探討薄管元件受撞擊時的受力及吸收能量多寡。
在挫曲變形動態行為中，了解撞擊過程中中空薄管元件的吸收能量的多寡，對於設計上將會有很大的幫助也能節省設計成本。在數值模擬分析方面，利用商業有限元素軟體LS-DYNA中的explicit solver模擬top-hat型薄管元件受軸向衝擊後的動態行為，並與文獻模擬分析之結果以及衝擊實驗之結果進行驗證比較。最後進一步對top-hat型薄管元件進行幾何改變，研究不同外型結構對於薄管元件吸收能量的影響。

The major purpose of this research is based on analyzing dynamic impact response of top-hat thin-walled sections which subjected to axial impact. Hollow thin-walled tubes usually applied in several of structure such as train, plane, car’s bumper and so on. The important intention of the thesis also focuses on whether the structure has ability to resist or absorb energy sufficiently during the impact process. This research studies dynamic impact response, force, energy absorption of the top-hat thin-walled sections when the thin-walled sections subjected to axial impact.
It will be a great assistance on designing and can reduce the cost by the way of knowing energy absorption of thin-walled tube while impact process. In view of numerical solution, using the explicit mode of FEM simulation software LS-DYNA to simulate dynamic action, and compare with the simulation result of reference also compare with the result of impact experiment. Finally, through changing the geometric of top-hat thin-walled sections, it could investigate whether the different construction will affect the energy absorption of the thin-walled sections.

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