非平面不對稱結構與彈性聯接振動分析

Out of Plane Vibrations Models of an Asymmetry Structure with Partially Clamped Joints

李坤韋(Kun-Wei Lee)

指導教授 ： 林水木

崑山科技大學/工程學院/機械工程研究所/碩士(2009年)

https://doi.org/10.6828/KSU.2009.00010

摘要

實際上桿件結合有完全剛性和非完全剛性之分。完全剛性結合的結構分析較普遍，非完全結合者較少研究文獻。本論文將研究完整的非完全結合結構的振動。非完全剛性連合的數學模式表示如下：兩個桿件間容許相對轉動，並以彈簧連接之。當彈簧常數為無限大時，表示完全剛性結合。另外，當彈簧常數為零時，就屬於鉸鏈結合。建立非對稱門架out-of-plane彎曲振動模式，推導其解析解，並求解實際材料的自由振動頻率與模態圖形。最後來探討旋轉彈簧常數、彎曲比例、桿件長度和抗彎強度等參數對自然頻率和模態的影響。

關鍵字

不完全剛性結合 ； out-of-plane振動 ； 解析解

並列摘要

In the practice, the joint of a frame may be partially or completely clamped. So far, its effect on the dynamic behavior has not investigated clearly. In this study, these joints are mathematically simulated and generalized as an elastic joint associated with a rotational spring constant. The elastic joint allows the rotational angle difference of joint between two connected elements. In addition, there exists the moment resistivity against the rotational angle difference. This moment resistivity is defined as a rotational spring constant. If the spring constant is infinite, the joint is completely clamped and the rotational angle difference is zero. In the other hand, if the spring constant is zero, the joint is hinged. Moreover, the bending vibration model of a general asymmetry frame with two elastic joints is established here. Its exact solution for the general system is derived. It is found that the effects of the rotational spring constants, the ratios of the bending rigidities and the element lengths on the vibration of a frame are significant.

並列關鍵字

elastic joint ； Out of Plane Vibration ； exact solution

參考文獻

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