2003-08-012024-05-18https://scholars.lib.ntu.edu.tw/handle/123456789/714207摘要：本研究計劃擬以理論解析及實驗的量測相互配合驗證，以了解層域系統受動力載荷的暫態應力波傳。計畫中將利用射線展開法，建立三維層域非對稱動態作用力波傳問題的數學模型解析解；本問題為應力波在有限域中的波傳，故有無窮多波的特性，本計畫主要以解析解作為基礎進行層域系統內的暫態應力及位移數值計算；在實驗方面將建立一套完整系統以模擬理論分析的邊界條件及動力加載方式。本實驗主要量測自由表面之暫態位移以與理論分析作比較，在確定了理論計算結果與實驗完全符合後，最後並利用實驗的結果及理論正解進行反算，求出層域系統的機械性質。計畫中所使用的波源由毛細玻璃管或鉛筆芯斷裂所產生的動力加載模擬為步階函數之點波源量測自由表面之位移，並利用simplex反算程序，再配合三維點波源作用於層域上的理論正解，如此可求得最佳化之材料參數。 本研究計劃之完成不但在學術上可了解應力波傳之物理現象，並建立應力波在界面的反射與折射波分析法，在實用上亦可於非破壞檢測材料性質的應用上提供新的量測方法。本計畫的內容涵蓋了理論解析﹐數值計算﹐實驗量測以及反算問題﹐內容相當完整而豐富且兼具學術與實用性。 <br> Abstract: In this research project, the theoretical analysis as well as experimental measurement will be conducted on the dynamic responses of a layered medium. We will develop the theory of transient wave propagation in a three dimensional configuration by the ray expansion method. Furthermore, the exact theory will be compared with the experimental results. We measure the vertical displacement of the layered medium on the top surface by applying a point force with step time function, which is obtained by the fracture break of a capillary or pencil lead. A optimization method based on the simplex algorithm together with the theoretical analysis is developed to obtain the material properties of the layered medium system from the waveform of the experimental measurement. A complete methodology of using the transient wave theory in estimating the configuration and material properties will be developed in this project.反算層域問題射線展開法動力載荷暫態應力波Inverse problemLayered mediumRay Expansion methoddynamic loadingtransient wave