有限元素模型更新方法於剪力屋架之應用

Application of Model Updating Methods to Shear Buildings

許姿瑋(Tzu-Wei Hsu)

指導教授 ： 楊永斌

國立臺灣大學/工學院/土木工程學研究所/碩士(2005年)

https://doi.org/10.6342/NTU.2005.00013

摘要

土木工程結構最大的特徵在於其龐大的尺度及施工的不確定性。以施工的不確定性而言，模型的更新比起任何一個領域都來的重要；以龐大的尺度而言，簡單而快速的更新方法最符合工程師所需。因此本文主旨便是在於發展實用的有限元素更新方法，而以建築結構最常利用的「剪力屋架」模型為研究主題。
有限元素模型更新的方法，大致可分為二大類：參數更新法和直接更新法。參數更新法因為可確保更新後矩陣的物理涵義而被廣泛接受，但其中所需的參數選擇程序極為棘手，本文因應剪力屋架模型的更新，提出新的參數選擇對策，不僅可包含大部份影響因子，也簡化了更新程序。另外，本文亦提出新的直接更新法，相較於已存在的直接更新法，新的直接更新法更為簡單易記，而其矩陣的物理涵義也可間接透過動力分析的結果證實。檢驗更新方法的可行性，我們模擬了數個建築物較常遭遇的情形，其結果是肯定的。

關鍵字

有限元素 ； 模型更新 ； 剪力屋架

並列摘要

The greatest characteristics of a civil engineering structure lie in its uncertainty of construction and huge scale. To account for the uncertainty of constructions, an important problem is to update the analysis model so that it can produce results as close as possible to those observed in field. As the scale of a structure is usually huge, a simple and fast method for model updating is the one most desired by engineers. The purpose of this thesis is to develop finite element model updating methods that are suitable for practical use. To facilitate the derivation, the most often used shear buildings are taken as the example of study.
In general, two categories of methods are used for model updating, i.e., the direct and parameter updating methods. The parameter updating methods were widely used because they can preserve the physical meanings of the updated matrices, but the procedure for determining the parameters is complicated. For buildings of the shear type, this paper presents a new way for selecting the parameters, by which the dominating parameters are preserved in the updating, while the procedure is greatly simplified. Furthermore, to circumvent the complicated procedures involved in parameter selection of the parameter updating methods, a direct model updating method is proposed. Compared with the existing ones, this method can be easily understood, while the physical meanings of the system matrices can be appreciated from the results of dynamic analyses. To demonstrate the applicability of the proposed updating methods, several typical examples that are likely to be encountered in practice were studied. It is confirmed that the proposed methods are workable.

並列關鍵字

finite element ； model updating ； shear building

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