本文之研究目的主要在於探討中空薄管元件受到軸向衝擊下之動態行為模式之研究。中空薄壁管件常見於各種結構體中，例如車體結構潰縮桿以及火車結構等等。而當管件結構遭受軸向衝擊時，是否有足夠的強度抵抗或吸收撞擊的能量一直是重要的研究方向。因此藉由瞭解中空薄壁管件在軸向撞擊下的動態行為模式，探討中空方形薄管遭受撞擊時，材料的受力、吸收能量與變形量多寡，可以用來預測中空薄壁管件的變形模式。
在挫曲變形動態行為中，瞭解撞擊過程中中空薄管位移的長短和能量吸收的多寡，對於設計上將會有很大的幫助。在理論分析方面，利用解析解求得平均力、位移、位移所需時間、能量及可生成之皺摺數目，並和實驗與模擬結果進行比較驗證。在數值分析方面，利用商用有限元素軟體LS-DYNA中explicit solver模擬動態實驗，並與衝擊實驗之結果數據以及理論數據進行驗證比較。進一步對薄管元件做幾何改變，研究不同外型結構對管件吸收能量的影響，並配合美國前方正面碰撞法規FMVSS208乘員安全法規之頭部傷害標準(Head Injury criterion)，觀察探討幾何改變的薄管元件與造成人類腦部傷害的關係。

The major purpose of this research is based on analyzing dynamic impact response of hollow thin-walled tube component which is subjected to axial impact. Hollow thin-walled tube usually appears in several of structure such as cars, bumper, train and so on. Besides, the important intention of the thesis also focuses on whether the structure has ability to resist or absorb energy sufficiently during the impact process. When thin-walled tube is subjected to axial impact, the transformation mode could be predicted by studying dynamic impact response, force, energy absorption or stroke of the tube.
It will be a great assistance on designing by the way of knowing stroke and energy absorption of thin-walled cube while impact process. In view of theories analysis, using analytic solution to obtain average force, stroke, duration time, energy and the number of collapse, and compare with experimental and simulated result. In light of numerical solution, using the explicit solver of FEM simulation software LS-DYNA to simulate dynamic action, make comparison between the result of impact experiment and theories analysis. Through changing the geometric of thin-walled tube, it could investigate the tube of energy absorption in different construction. In the meantime, utilizing Head Injury criterion (HIC) of FMVSS208 observes the connection between geometrical deformation of thin-walled tube and causing brain damage for human.

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