光彈應力分析是一種很普遍且有很多研究的技術。我們可以透過光彈實驗得到具相同主應力方向點的軌跡，與相同主應力差值點之軌跡，此兩組數據為光彈應力分析中之重要參數。
本文以有限元素法，模擬模型於受負載及邊界條件作用下，由所得之受力模型應力分佈情況，轉換成散射式光彈之條紋影像，並利用實驗方式所得到條紋圖像來與模擬所得條紋圖像作比較驗證。以有限元素模擬光彈應力分析中，散射式光彈中沿光通過路徑其次主應力方向改變之條紋影像。
研究中L型模型模擬次主應力方向沿光線路徑方向改變的光彈條紋，並使用不同厚度的散射光以及沿著模型變形方向的散射光，經實驗所得條紋圖像與模擬所得條紋圖像比對，可得到相當吻合的結果。
經由簡化光強度搭配有限元素法所得到的數據，模擬並討論兩者間的差異。使用簡化的方程式與二力法結合，求出次主軸應力方向，並與實驗結果比對，討論誤差的原因。

The photoelastic stress analysis is a technology with many researches focus on it. We can acquire the locutions of points with the same principle stress direction and the principle stress difference through the photoelastic experiments These data are the important parameters in photoelastic stress analysis.

The main purpose of this article is using Finite Element Method to simulate the distributions of stress when model Bear loadings and boundary conditions, then turn these into the intensities of lights to simulate the fringe patterns of scattered-light photoelasticity. And compare these results with the patterns of photoelastic experiments. We use Finite Element Method to simulate the isoclinic and isochromatic patterns of photoelasic experiments and the fringes while the secondary principle stress varies along the path of light and the secondary principle direction fixed.

Using the L shape model to simulate the fringes while the secondary principle stress varies along the path of light, and use scattered-light of different thickness and transform scattered-light of direction along with the model. The simulation fringe pattern compare with the experiment pattern, can be quite identical results.

Through the simplification of intensity with the finite element method of data. simulation and discuss both the difference. The use simplifies equation and two-load method union, solving secondary principle stress direction, compares with the experimental result, and discuss the reason of error margin.

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