Vibration Analysis of a Beam with Intermediate Flexible Constraints Subject to a Moving Load of Constant Speed
陳南吉、林海平
E-mail: [email protected]
ABSTRACT
In this study, a hybrid numerical/analytical method that permits the efficient calculation of dynamic characteristics of a beam with intermediate flexible constraints subject to a moving load of constant speed is presented. First, assuming the beam obeying the Euler-Bernoulli beam theory, the equation of motion of the system is derived. By using transfer matrix method, eigensolutions (natural frequencies and mode shapes) of the beam system can be determined. Afterwards, the intermediate flexible constraints subject to a moving load of constant speed is analyzed, and the forced response of the moving load can be obtained by applying the model expansion theory and the orthogonality of the mode shape function. In the results, the dynamic deflection of the intermediate flexible constraints subject to a moving load can be effectively reduced. Moreover, different supporting spring and supporting position have different influences on the dynamic responses of the beam structure. The static and dynamic characteristics of the beam structure were analyzed in this article, and a experimental method was used to validate the theoretical mode.
Keywords : Euler-Bernoulli, transfer matrix, eigensolutions, model expansion theory, orthogonality Table of Contents
封面內頁 簽名頁 授權書...iii 中文摘要...iv 英文摘
要...v 誌謝...vi 目錄...vii 圖目
錄...ix 表目錄...xiii 符號說明...xiv 第一章 緒 論...1 1.1 研究動機...1 1.2 文獻回顧...2 1.3 研究方法及本 文架構...5 第二章 分析方法...7 2.1 樑之各種邊界情形之介紹...7 2.2 Euler-Bernoulli 樑之運動方程式...10 2.3 具彈簧支撐之Euler-Bernoulli 樑分析...13 2.4 分析具單一等速移動負荷 之彈簧支撐樑...25 2.5 側向位移響應的收斂性情形與r 值的關係...30 第三章 結果與討論...32 3.1 實驗量測分析...32 3.2 實驗結果與比較...40 第四章 結論與建
議...70 4.1 結論...70 4.2 建議...71 參考文 獻...72 附錄A.1 ...75 附錄A.2 ...76 REFERENCES
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