高層建築橫風向氣彈研究

機構典藏 > College of Engineering > Graduate Institute & Department of Civil Engineering > Thesis > Item 987654321/34524

Please use this identifier to cite or link to this item: https://tkuir.lib.tku.edu.tw/dspace/handle/987654321/34524

Title:	高層建築橫風向氣彈研究
Other Titles:	Aeroelasticity of a high-rise building in across-wind direction
Authors:	王軍翰;Wang, Chun-hang
Contributors:	淡江大學土木工程學系碩士班吳重成;Wu, Jong-cheng
Keywords:	高層建築;橫風向;鎖定;間接預測法;直接預測法;high-rise building;Across-Wind Direction;Lock-in;Indirect Prediction Method;Direct Prediction Method
Date:	2009
Issue Date:	2010-01-11 05:20:57 (UTC+8)
Abstract:	受風結構之反應在不同之外型、流場、質量與阻尼影響下，其振動行為皆不同，尤其當結構反應與風場形成互制時，對結構安全將造成嚴重威脅。隨著風工程的發展，對於高層建築而言，目前順風向反應的理論發展較為完備，橫風向反應則因渦散現象引起之非線性氣彈力影響，尤其是理論與實驗資料之關連性建立仍在發展中。眾所皆知，設計高層建築時應盡量避免產生橫風向鎖定共振，因此大部分的文獻皆在討論風速未達產生鎖定共振之前的行為。本論文之目標則在探討鎖定共振狀態下之橫風向反應，藉由風洞試驗，配合提出之「間接預測法」與「直接預測法」，進行氣動力參數之識別，期能在爾後根據此模式建立橫風向氣動力參數之資料庫，預測實際建物之橫風向反應。本文所謂間接預測法乃是利用二維模型的氣動力參數預測高層建築之氣動力參數；而直接預測法則是直接根據三維模型反應進行高層建築氣動力參數之識別。進行風洞試驗之高層建築模型尺寸為10cm10cm70cm，直接預測法使用追蹤共振法中的遞增共振法及時間域曲線擬合法進行氣動力參數識別，以轉動慣量分類計有三組模型，標定為模型(Scr3=0.2494、Mr=0.0350)、模型(Scr3=0.3788、Mr=0.0174)及模型(Scr3=0.1923、Mr=0.0135)。直接預測法所識別出的氣動力參數代回理論式均與實驗值相符，顯示其正確性。因模型(Scr3=0.1923、Mr=0.0135)與二維模型有對應關係，在假設高層建築模型沿高度方向為氣動力均佈情況下，使用間接預測法之結果仍顯示橫風向振幅之理論值比實驗值小，因此間接預測法理論尚存在盲點待解決。 Wind-induced responses of structures are affected by many factors, such as the structure shape, flow condition, mass and damping. Especially when the excessive structural response (if it exists) is interacted with the wind flow and thus the so-called aero-elasticity forms, the structural safety will become of great concern to engineers. By the recent development in wind engineering, the investigation of the along-wind effect on high-rise buildings has grown more completely, while the researches on the across-wind effect, in particular the theoretical link with experimental data, are still remain challenging. It is well recognized that the lock-in and resonance effect in the across-wind motion of high-rise buildings should be mostly avoided, which initiate many researches that mainly focuse on the building response ouside the lock-in stage. However, this study aimed at investigating the across-wind resonance effect by identifying the aerodynamic parameters via wind tunnel measurements. Two approaches were proposed for the identification. One is called indirect prediction method which predicts the aerodynamic parameters of high-rise buildings by modifying the aerodynamic parameters of the two dimensional section model, while the other is called direct prediction method which directly utilizes the experimental measurement from the high-rise building model to identify the aerodynamic parameters. The test model in the wind tunnel is a high-rise building model with dimensions 10cm10cm70cm. The Growth-to-Resonance method accompanied with a curve-fitting optimization technique were adopted in the direct prediction method for the identification of aerodynamic parameters. Three different configurations of the test model, categorized by different moments of inertia, were set and tested in the wind tunnel. They were denoted as Model (Scr3=0.2494、Mr=0.0350), Model (Scr3=0.3788、Mr=0.0174) and Model (Scr3=0.1923、Mr=0.0135). The identified results have been verified by observing the good correction between the experimental and theoretical responses in the time domain. Since Model (Scr3=0.1923、Mr=0.0135) has the dynamic similarity to the two-dimensional section model that was previously chosen, its experimental results were used to make comparisons with those using indirect prediction method. It was found that the calculated amplitude from the indirect prediction method is always smaller than the experimental ones even by assuming that the parameters are aerodynamically uniformly distributed. A more thorough investigation to clarify this unreasonable outcome will be pursued in the future study.
Appears in Collections:	[Graduate Institute & Department of Civil Engineering] Thesis

Files in This Item:

File	Size	Format
	0Kb	Unknown	300	View/Open

Loading...