由於不同材料有著不同的特性，結構的界面角因幾何形狀與材料性質的不連續性，那麼應力奇異性和震盪性通常就會發生其中，並且引發結構的不穩定甚至是破壞，設計一個合適的結構鍵結來預防破壞的發生是非常重要的。
本文主要透過與應力奇異性最直接相關的兩項參數：應力奇異階次、應力強度因子，並且以史磋公式發展的異向性彈性力學之解析解為基礎，探討界面角、界面裂縫問題、平底剛體接觸問題，推導出壓電材料以及磁電彈材料之應力奇異階次明示解。應力強度因子部分，採取與路徑無關的H積分來做應力強度因子的計算，使計算應力強度因子中所需要使用到的高斯點物理量遠離裂縫尖端，避免奇異性問題的產生。最後示範奇異階次以及應力強度因子在實際例子上的應用。

Different materials have differrnt properties. Due to the mismatch of elastic properties, streee singularity and oscillation usually occurs near the interface corner, which may initiate failure of structures. Therefore, it is important to design a proper joint shape to prevent the failure initiation and propagation.
In this study, based on the Stroh Formalism and the two special characteristic: singular order and stress intensity factor which are highly relevant to the stress singularity. I am going to deal with the interface corners, interface crack problem, and flat-ended punch problem. Also, the new explicit solution of singular order in piezo material and MEE material are published. In order to overcome the singularity around the corner and the end of the punch, the path-independent H-integral is used to compute the mixed-mode stress intensity factor. In the end, I will show how we can established these two parameters on the real case in our life.

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