利用微振實驗資料識別橋梁及建築物之動力參數

Using the Data of Ambient Vibration Tests to Identify the Dynamic Parameters of Bridges and Buildings

林智勇(Chih-Yung Lin)

指導教授 ： 呂良正

國立臺灣大學/工學院/土木工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.01246

摘要

微振量測實驗與系統識別的技術在近年來已經十分普遍，如對建築物進行微振量測，再利用系統識別即可得建築物的基本振動周期；又如對高科技廠房進行微振量測，可得廠房之振動量並和振動規格比較。因此可見微振量測於實務上的應用已經相當廣泛，本文將介紹系統識別的方法與微振量測的應用。
台灣由於位在環太平洋之地震帶上，大小地震頻繁，尤其在九二一地震後，建築物的耐震能力成為大眾關切的話題，而基本振動周期與阻尼比為建築物耐震設計之主要結構參數。然而對於大規模數量的建築物阻尼比，相關的文獻記載並不多，因此蒐集大量建築物的微振量測資料並找出建築物物理特性與阻尼比的關係是有其研究價值的。
本文另外對於利用微振量測求得橋梁的自然振動頻率與模態振形，並與SAP2000模型模態分析結果比較。最後介紹橋梁的靜態與動態載重實驗，並利用微振量測求得橋梁之動力放大因子，再與規範公式所得到的動力放大因子比較。

關鍵字

阻尼比 ； 微振量測 ； 系統識別

並列摘要

The ambient test and the skillof system identification are very popular in recent years,like the ambient test of buildings,by using the skill of system identification can get the period of buildings.
It is quite common that the period of a building can be identified easily and accurately from ambient test recorded in that building. However, this is not true for damping ratios. It is found that identified damping ratios vary to some extend depending on the identification methods, the strong motion records, and the floor levels where the strong motion was recorded. This study is going to investigate how these happen and is hoping to suggest proper values of damping ratio for the design of steel and RC buildings in Taiwan.

並列關鍵字

ambient test ； damping ratio ； system identfication

參考文獻

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