中空方形薄管動態挫曲之數值研究

Numerical Study on Dynamic Crush of Thin-Wall Square Tube

郭書豪(Shu-Hao Kuo)

指導教授 ： 趙修武

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400693

摘要

中空薄壁管件具有高強度重量比特性，常見於各種結構體中。考慮結構遭受高速衝擊時，是否有足夠的強度抵抗或吸收撞擊的能量，一直是這類問題研究的重要方向。本研究為中空薄壁管件在高速衝擊下的動態行為模式，了解有關材料的受力、吸收能量與變形，可以用來預測中空薄壁管件的變形模式。
在理論分析方面，以平均受力的方式來預測材料挫曲變形時可能所需的能量，截面柱上之平均受力為材料種類與截面尺寸的函數。在數值分析方面，採用動態分析軟體LS-DYNA，對中空方形薄管挫曲行為進行數值分析。改變不同計算參數，使計算結果與實驗值吻合，以建立模擬的參數進而討論方管凹陷處參數改變對挫曲行為的影響以及吸收能量的多寡。

關鍵字

動態挫曲 ； 凹陷參數

並列摘要

Thin-wall tubes due to its advantage in high strength-weight ratio are widely used in many structures. For structures under high-speed impact, the main issue is to obtain required strength to absorb impact energy. This thesis investigated the dynamic behaviors of thin-wall square tubes under high-speed impact. The load, energy absorption and deformation of thin-wall square tubes were analyzed numerically.
First, the mean load method was applied to predict the mean load during the buckling process. Second, the software LS-DYNA was employed to study the buckling behavior of thin-wall square tubes. Though the comparison with experimental data, a suitable set of parameters was found in order to have the numerical results in good agreement with measurement. And last, the buckling behaviors of thin-wall square tubes with different indentations arrangement were systematically studied. The advantages and disadvantages among those arrangements were quantitatively discussed.

並列關鍵字

dynamic crush ； indentation parameters

參考文獻

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