结构载荷及参数识别是结构动力学领域的重要研究内容,目前已有一些研究致力于两者的联合识别。比如作者提出的EGDF方法,它虽然可以连续识别未知载荷和参数,但它需要已知未知载荷自由度上的加速度响应。另外,该方法与其他基于最小二乘的连续识别方法一样,存在未知载荷和位移识别的低频漂移现象。本文提出了上述问题的改进方法,将识别问题转化为模态空间中的模态位移以及模态载荷的识别,再利用模态缩减法,得到实时的EGDF法。另外,采用位移和加速度作为测量响应,来解决识别结果的低频漂移问题。
Abstract
Structural load and parametric identification are important contents in structural dynamics field. At present, there are some studies focusing on joint identification of them. The extended GDF (EGDF) method presented here by the authors has the ability to continuously identify unknown loads and parameters. However, it is necessary to know acceleration responses at locations unknown loads exerted on. Besides, like other identification methods based on the least square, the EGDF method has low frequency drift phenomena of identified unknown loads and displacements. Here, a modified method was proposed to convert this recognition problem into the recognition of modal displacements and modal loads in modal space, and then the modal truncation technique was used to obtain the real-time EGDF method. Furthermore, taking displacement and acceleration as measured responses, the data fusion technique was used to solve low frequency drift problems in identification results.
关键词
载荷识别 /
参数识别 /
GDF法 /
模态缩减 /
数据融合
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Key words
load identification /
parameter identification /
the GDF algorithm /
modal truncation /
data fusion
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参考文献
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