臺灣博碩士論文加值系統

超高建築為今日之都市建設發展之必然趨勢，同時日益複雜的建築物設計系統上所造成的建物之質量中心與勁度中心偏離問題不容被忽視，其可能會影響樓層層間位移、振動加速及扭轉向振動的變化，故高層結構物受風力作用的情形及高層結構物與流場間的關係是我們必須了解及探討的。
為了有效掌握建築物所受風力影響，本研究將高層建築簡化為二維之矩柱斷面，於風洞實驗室中使用自由振動的方式，在平滑流場下以不同深高比的矩柱、改變振動與扭轉之頻率比、順風向上不同之偏心量及不同阻尼等控制變因，來觀察矩柱體在橫風向及扭轉向產生的氣彈反應，及結構物表面之壓力變化及其尾跡的現象。
實驗結果顯示當勁度中心朝上游處偏心時，不同頻率比之橫風向擾動位移，皆會因偏心量的增加而造成臨界風速時的反應值被抑制，反之，當勁度中心朝下游處偏心，反應皆提昇，且會因頻率比越接近1.0使得負值氣動力阻尼會隨著偏心量的增加越大，因而促使反應值得急劇放大。另外，因為阻尼會抑制結構物振動時振幅的大小，因此高阻尼試驗不管是在扭轉向或橫風向擾動位移皆會比低阻尼要來的小，但是並不會明顯影響到偏心對於整體的反應。
在結構物振動與尾跡渦散方面，勁度中心往下游偏心增加時，結構物橫風向振動與氣流間的交互作用會隨之加強，因而造成尾跡渦散的能量強度明顯提升。反之，模型橫風向位移與氣流間交互作用漸小，導致尾跡渦散頻譜有下降的趨勢，此與橫風向擾動位移及擾動昇力現像一致，且能相互的印證。

The high-rise building plays a major role in construction development of modern cities. The eccentricity of the structural system cannot be neglected in modern designs.Thus the effects of wind on high-rise buildings and the interactions between these two have become main research topics.
In order to control the influence of wind , this research simplified the high-rise building into a 2-D rectangular section. In order to observe the aeroelastic responses of these rectangular cylinders, we applied the method of free vibration in the wind tunnel, used different depth-to-height ratios, changed the frequency ratios of vibration and torsion,used different damping ratios, and applied the control factor to obtain different eccentricities of the cylinders in the along-wind direction.
The experimental results show that when the geometric center is located above the mass center, the fluctuating displacement decreases in the across-wind direction, and vice versa. Increases in the eccentricity enhance the relative changes, when the frequency ratio is close to1.0, the fluctuating displacement also increases, the damping ratio restrains the response, thus a high damping ratio reduces the fluctuating displacement.

中文摘要………………………………………………………………I
英文摘要………………………………………………………………II
目錄……………………………………………………………………III
圖目錄…………………………………………………………………VI
第一章 緒論 1-1
1-1 前言 1-1
1-2 研究動機 1-1
1-3 研究方法與內容 1-2
第二章 文獻回顧 2-1
2-1 橫風向振動 2-1
2-1-1 橫風向振動對壓力係數之影響 2-2
2-1-2 橫風向振動對尾跡之影響 2-5
2-2 扭轉向振動 2-5
2-2-1 扭轉力矩與扭轉角的成因 2-6
2-2-2 扭轉振動的氣彈力現象 2-7
2-3 風壓之量測 2-8
2-4 尾跡實驗量測 2-8
2-5 深高比（B/D）對風力係數之影響 2-8
第三章 理論背景介紹 3-1
3-1 風力係數 3-1
3-2 風對結構物之作用 3-2
3-2-1 氣動力現象 3-3
3-2-2 氣彈力現象 3-5
3-3 散漫數據分析 3-6
第四章 實驗配置、量測與數據分析 4-1
4-1 風洞簡介 4-1
4-2 模型之設計及配置 4-1
4-2-1 氣彈模型之設計 4-1
4-2-2 昇力模型之設計 4-3
4-3 實驗設置 4-3
4-3-1 結構物模擬 4-4
4-3-2 採樣程序 4-5
4-3-3 量測設置 4-5
4-4 結構動力特徵 4-5
4-4-1 結構阻尼率定 4-5
4-4-2 自然頻率率定 4-6
4-5 儀器之率定及校正 4-6
4-5-1 位移率定 4-6
4-5-2 TSI定溫式熱膜探針之率定 4-7
4-5-3 壓力轉換器之率定 4-8
4-5-4 管線系統訊號的校正 4-8
4-6 位移反應量測 4-10
4-7 壓力反應量測及分析 4-10
第五章 結論與討論 5-1
5-1 順風向偏心之位移實驗結果 5-2
5-1-1 勁度中心往下游處偏心之實驗結果 5-2
5-1-1-1橫風向擾動位移反應 5-2
5-1-1-2 扭轉向擾動反應 5-4
5-1-2 勁度中心往上游處偏心之實驗結果 5-7
5-1-2-1橫風向擾動位移反應 5-7
5-1-2-2扭轉向擾動反應 5-9
5-2 擾動昇力係數反應 5-11
5-3擾動昇力頻譜分析 5-13
5-4 結構物振動對尾跡渦流之影響 5-14
5-4-1尾跡頻譜 5-14
5-4-2 尾跡與橫風向位移反應之交相關性 5-16
第六章 結論 6-1
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