本文利用小波轉換針對結構響應訊號含有雜訊影響的情況下進行結構損傷偵測分析，先利用小波良好的時頻解析能力偵測出結構損傷發生的時刻，並利用系統識別理論配合二階段損傷偵測法進行結構損傷位置和損傷情況之分析。本文提出「損傷能見度」指標，以區別損傷信號和雜訊，使小波偵測方法可以有效地標定損傷發生時間。在進行損傷位置標定時，吾人提出模態曲率的改良作法並配合小波轉換使能更有效地標定損傷位置。最後進行損傷情況評估，針對可能損傷的位置分別計算Lipschitz指數估測其損傷程度。數值模擬分析結果顯示，本文所提出的結構損傷偵測分析法在含雜訊的情況下仍具有良好的精確性。

In this thesis, structural damage detection analysis is studied by means of wavelet transform. It offers an alternative and flexible way of providing time-frequency information when structural damage occurred in detecting time. In the process of damage detection, a two-step method combination with system identification technique is employed. The damaged visibility method could be distinct from noise and damaged signal during the structural damage occurred within the detecting time. A modification to the conventional mode shape curvature method combination with wavelet transform is proposed to improve the efficiency of wavelet detective method. As a result, the possibly damaged locations in a structure can reliably be located. Lastly, the damage extent of possibly damaged locations is then evaluated using the Lipschitz exponent. Numerical simulation results show that the proposed method is accurate under noisy conditions.

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