本文以智能層(SMART Layer®)系統為基礎，深度探討整套系統背後的架構與診斷方法，並輔以藍姆波(Lamb wave)之波傳理論作學理分析與驗證，以及SMART Layer®系統在結構健康監測(Structural Health Monitoring, SHM)上的實務應用，評估SMART Layer®系統監測金屬結構疲勞裂紋之成效。
SMART Layer®系統之感測器與致動器皆使用壓電材料鋯鈦酸鉛(PZT)，當漢寧窗訊號輸入貼在金屬平板結構表面之SMART Layer®致動器，藉由壓電效應將電能轉為機械能，從而在金屬平板中激發出藍姆波，該應力波在結構中運行一段距離後，再由貼在結構表面之感測器接收。SMART Layer®利用感測器所接收之訊號加以處理，將第一抵達波包的訊號之變化以損傷指數(Damage Index, DI)量化之，顯示結構的健康狀況。
本研究透過藍姆波之特徵方程式求解出群速度、相速度之色散曲線，並整合到SMART Layer®訊號之研究。在應用上群速度色散曲線能判別波包模態與模擬藍姆波單一模態之時間寬度，而相速度則能模擬藍姆波單一模態波形。經模擬後發現藍姆波的時間寬度、波形之趨勢符合實驗之觀測，顯示分析模型之準確性。
在SMART Layer®偵測金屬結構裂紋部分，本研究聚焦於S0訊號，並透過權重因子之計算整合9條感測路徑之DI，再與標準試驗件之疲勞裂紋一同建構出實驗趨勢，以觀察疲勞裂紋增長對不同頻率藍姆波訊號的影響。透過本研究之結果驗證，SMART Layer®系統可有效偵測金屬結構之疲勞裂縫。
本研究出本論文著重於研究SMART Layer®系統在應用上的分析方法，以實務層面可以輔助判斷SMART Layer®訊號資訊以及損傷所帶來的影響，為結構健康情形之評估奠定重要基礎。

Based on the SMART Layer® system, the diagnoses for damages in metallic structures were developed in this study. To understanding the operation principles of SMART Layer®, the theory of Lamb wave was also investigated and then validated with the experimental observations. Finally, the application of SMART Layer® on Structural Health Monitoring (SHM) was presented.
The piezoelectric material PZT, which can excite Lamb wave in the plate-like structure, is adopted for SMART Layer® system. When the damage exists in the structure, SMART Layer® system can calculate Damage Index (DI) in First Arrival Window (FAW) to evaluate the damage size in the structure.
In order to validate the signal process of the SMART Layer® system, the dispersion curves of the Lamb waves are investigated by theoretical approach. The predictions of time duration and waveform had a good agreement with signal from experiments.
For the experiments on fatigue crack monitored by SMART Layer®, the S0 mode of Lamb wave was selected for detection. The results showed that DI is strongly affected by different loading and excited frequency. The results of the present study showed that the fatigue cracks in the metallic structure can be detected by the SMART Layer® system.

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