HHT振動解析法應用於軌道扣件檢測研究

Study of Inspection on the Track Fastener by Hilbert Huang Transform

陳明新(Ming-Hsin Chen)

指導教授 ： 張達德

中原大學/工學院/土木工程學系/碩士(2006年)

https://doi.org/10.6840/cycu200600516

摘要

摘 要
關鍵字：經驗模態分解法、快速傅立葉分析、希爾伯特-黃轉換
鐵路因行車密度大、速度快之特性，因此軌道系統的完整性，就變成相當重要的課題，本研究以希爾伯特-黃轉換與快速傅立葉轉換對扣件鬆脫頻率作一系列研究，實驗一開始先在中原大學實驗室做小區段試驗，尋找鋼軌自然振動頻率，再至現地台鐵試驗場做現場試驗，確認鋼軌自然振動頻率後，將扣件鬆脫分別做實驗室與試驗場扣件鬆脫試驗，以找出其頻率變化值。
研究結果確認鋼軌水平向自然頻率為300~450 Hz，垂直向自然頻率為600~900 Hz。扣件鬆脫試驗結果發現在水平向頻率變化最為明顯，而在垂直向頻率變化不大，因此確認檢測扣件鬆脫頻率變化時，宜檢測水平向的頻率變化值，即可檢測扣件有無鬆脫。而在快速傅立葉轉換解析中，因將訊號轉至頻率域中時，其時間的資訊便會失去，也就是說我們無法得知其即時頻率，且傅立葉解析法對於非穩態、非線性的訊號無法進行有效之解析。而希爾伯特-黃轉換解析法對非穩態、非線性訊號具有較佳的解析，且可以得到即時頻率變化值。

關鍵字

希爾伯特-黃轉換 ； 經驗模態分解法 ； 快速傅立葉分析

並列摘要

ABSTRACT
Key Word：Empirical Mode Decomposition, Fast Fourier Transform Analysis, Hilbert-Huang Transform
Because railway is high speed.Therefore ,completeness of track,which become quite important subject.Research this with Hilbert-Huang Transform and Fast Fourier Transform is it is it take off to fastener frequency make a series of study.Testing in the laboratory of Chung Yuan Christian University at the beginning in experiment.Looking for the natural frequency of rail first, and then test in Taiwan Railways Adminstration. After confirming the natural frequency of rail , take off the fastener and make the laboratory and in-situ test, in order to find out
its frequency changing value.
The result of study that the rail level natural frequency is 300~450 Hz, vertical natural frequency 600~900 Hz. The fastener takes off the result of the test and finds that it is most obvious to change frequency of the level, in vertical to change unobvious. Fast Fourier Transform analyzes, while shifting signal to the frequency region, its time's information will lose, that we are unable to know their instant frequency. Fast Fourier Transform analytic method to non-stationary, non-linear signal unable to effective analysis. Hilbert-Huang Transform analytic method to whether stationary,non-linear signal have better analysis,and
can receive the instant frequency changing value .

並列關鍵字

Hilbert-Huang Transform ； Fast Fourier Transform Analysis ； Empirical Mode Decomposition

參考文獻

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