臺灣博碩士論文加值系統

本文探討具拘束阻尼層(Constrained Layer Damping,CLD)部份覆蓋樑之振動與阻振分析。在理論推導方面，利用Mead與Markus之拘束阻尼層變形理論為本及運用平衡關係式，續採用漢米爾頓原理，並嘗試以正解(exact solution)求之。推導出僅含兩個位移變數之具拘束阻尼層部份覆蓋樑之運動方程式。所導出之運動方程式，在自由振動分析方面，以不同覆蓋位置及不同覆蓋面積，分析固有頻率與固有模態之變化情形。文末並進行CLD之實驗分析，量測不同覆蓋位置及不同覆蓋面積對樑結構之阻振效果的變化情形。
本研究結果，可使工程人員瞭解不同覆蓋拘束阻尼層結構阻振的效應，也可於評估不同結構抑振及貼覆位置方面，提供有用的資訊，具有工程應用之價值。

This thesis presents the vibration and reduction analysis for partial constrained layer damping(CLD) treatment of beams. The equations of motion of beam with partial CLD treatment are derived by energy principle and equilibrium relations. This model, unlike the previous, used just two displacement functions：one is the in-plane placement and the other is the transverse displacement of beam. In the free vibration, the frequencies and the mode shapes in a sense of exactness are solved for various coverage ratios and different coverage positions. Experimental analysis on PCLD are conducted to measure the vibration reduction quantities and compare to the theoretical results.
The derived theory and obtained results hopefully would provide, the engineers very useful information in evaluating vibration reduction for different constrained layer damping (CLD) treatment of beams.

摘要 I
ABSTRACT II
誌謝 III
目錄 IV
圖表索引 VII
符號索引 X
第一章 緒論 1
1.1文獻回顧 1
1.2研究動機與目的 3
1.3 本文架構 4
第二章 具拘束阻尼層部分覆蓋樑之理論分析 6
2.1具拘束阻尼層覆蓋之三層樑理論 6
2.1.1應力、應變、位移關係式 7
2.1.2黏彈材料之基本假設 8
2.2三層樑結構之能量式 11
第三章 運動方程式之推導與邊界條件 14
3.1三層樑結構之平衡關係式 14
3.2系統之運動方程式 16
3.3系統之邊界條件與相容條件 21
3.3.1系統之邊界條件 21
3.3.2系統之相容條件 21
3.4系統之頻率方程式 27
第四章 系統之自由振動分析 32
4.1系統之固有頻率與模態 32
4.1.1固有頻率 33
4.1.2固有模態 34
4.2具拘束阻尼層部份覆蓋樑之固有頻率分析 36
4.2.1不同覆蓋位置對頻率之影響 36
4.2.2不同覆蓋面積對頻率之影響 37
4.3具拘束阻尼層部份覆蓋樑之固有模態分析 38
4.3.1不同覆蓋位置對固有模態之變化情形 39
4.3.2不同覆蓋面積對固有模態之變化情形 39
第五章 各模態阻尼之能量分析 50
第六章 實驗架設與結果 57
6.1實驗架設 57
6.1.1量測設備 57
6.1.2分析系統 59
6.2實驗結果與比較 60
6.2.1不同貼覆位置之時域響應 60
6.2.2不同覆蓋面積之時域響應 61
第七章 結論與未來展望 72
7.1結論 72
7.2未來研究方向 73
參考文獻 75
附錄 78
作者簡介 81

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