隨著科技的日新月異，生活中的種種東西也越來越逼近製造的極限，舉凡日常用品、交通工具、高樓大廈橋梁結構、甚至是工廠端的精密儀器都是，而這些東西在剛出廠的時候即使完整，經過一定的時間之後本身的可靠度或是完整性終究會慢慢損壞，為了檢測這些處在結構本身的損害，不用破壞結構即可判別是否損壞的振動檢測法因應而生，因此本研究先以有限元素軟體模擬梁狀結構的損壞，找出完整與損壞後結構之中應變能的變化情形差別，再依此差異界定判斷損壞的標準，並且設計一套能夠僅用加速規找出應變能差異進而判斷並定位結構中損壞的方法。
本研究一開始先介紹非破壞性振動檢測過去的歷史以及發展過程，先說明本研究會用到的方法之前的基礎理論以及演進過程，再用有限元素分析軟體模擬梁結構的應變能變化情形，後續觀測出當結構破壞時會出現的關鍵特徵後，進行不同邊界條件的模擬情況觀察關鍵特徵是否依然存在，並且界定出適用此方法須滿足的條件以及適用範圍。而後續去設計一套數學方法，以滿足僅用加速規便可以觀察結構的應變能變化，當模擬輸出的數據能夠判斷結構是否損壞的關鍵特徵後，再設計與模擬情況符合的實驗，使用完整結構與破壞後結構搭配加速規以及鐘擺敲擊，用實驗數據帶入前述的數學方法檢測結構的損壞並與模擬的結果進行比較，為此新式應變能方法的驗證。
本研究設計了一種僅需要使用簡單儀器的新應變能方法，能透過比較應變能變化差異判斷並定位結構破壞，研究透過模擬及設計實驗驗證了此方法的可行性。

Due to the rapid development of technology, all kinds of things are getting closer the limit of manufacturing, such as daily necessities, vehicles, bridge and high-rise buildings, and even precision instruments. Even if everything was complete when been finished. There is always with degeneration when times going on. To detect the damage of these structures, the vibration detection method that can judge whether the damage is damaged without destroying the structure is developed accordingly. This study using finite element method software to simulate the damage of a beam-like structure first, figure out the different between the complete and the damaged structure. Then define the standard for judging damage based on these differences, and devise a method that can only use accelerometer to find out the difference of strain energy to judge and locate damage in structures.
At the beginning of this study, the past history and development process of vibration detection are introduced, and the basic theory and evolution process before the methods used in this study are explained first. Then using finite element analysis software to simulate the change and transfer of the strain energy in the beam-like structure. Figuring out the key features that can represent the damage of the structure, simulating in different boundary conditions to observe if the key feature still exist, then according to these to define the conditions to be met and the scope of applications of this new strain energy method. In order to achieve goal that only using accelerometers to detect the change of the strain energy, to devising a mathematical method for analyzing the accelerations. After the key feature of the damage could be judging by the mathematical method, arrange an experiment which fitting the simulation.
Using accelerometers to detect the vibration of the complete and damaged structures hit by a pendulum, then compare the analysis result of the acceleration data from simulation and experiment, to derive a new strain energy method for damage detection and verification.

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