本文主要在求解含兩孔洞之無窮平板承受機械負載之應力場，並計算孔洞邊界之切向應力。首先利用映射函數將兩並列孔洞轉換成同心圓孔洞，意旨由物理平面轉換至數學平面，再藉由解析連續以及交替法等方法，計算所需函數。研究中根據Muskhelishvili等向性二維彈性力學基本公式，藉由邊界上的應力連續以及位移連續之條件，利用交替法計算求得應力場。得到應力函數後，藉由應力公式計算孔洞邊界的切向應力，並探討改變孔距及施力方向對於切向應力之影響。孔洞的排列方向與負載的角度不同，隨著孔洞間距縮短時會有截然不同的趨勢，排列方向平行的情況中，孔距縮短使最大應力下降；排列方向垂直的情況中，孔距縮短使最大應力上升。應用在骨板上，減少各螺絲孔洞間的距離能有效減少最大應力，進而提升疲勞壽命。

The solution for the stress field of two holes embedded in an infinite plate subject to a remote uniform load is provided in this article. First, the mapping function is used to convert the two holes in the physical plane to the concentric holes in the mathematical plane, and then the stress functions can be obtained by analytical continuation theorem together with the alternation method. According to the basic formula of Muskhelishvili isotropic two-dimensional elasticity, the stress field is calculated by satisfying both the stress and displacement continuities across the boundary. The tangential stress on the hole boundary can then be obtained and the influence of changing the distance between two holes and the direction of a remote uniform load on the tangential stress is discussed in detail. The results presented in this study can be applied to the bone plate that decreasing the distance between the screw holes can effectively reduce the maximum stress, thereby increasing the fatigue life.

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