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，轉換成光彈實驗中之光強度，以模擬穿透式及散射式光彈之條紋影像，並利用實驗方式來與模擬所得條紋圖像作比較驗證。主要是以有限元素模擬光彈應力分析中，等傾線、等色線及散射式光彈中沿光通過路徑其次主應力方向改變與次主應力方向不變之條紋影像。
在穿透式光彈條紋的模擬，使用圓盤模型來模擬平面偏光場與圓偏光場皆可得到不錯的結果。在散射式光彈條紋圖像模擬，使用圓盤模型來模擬光彈條紋，設定偏極化方向及觀測角皆為45度，得到的模擬圖像非常趨近於理論解模擬結果，得到不錯的結果。使用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，經實驗所得條紋圖像與模擬所得條紋圖像比對，亦可得到相當吻合的結果。

The photoelasticity 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 photoelasticity experiments These data are the important parameters in photoelasticity stress analysis.
The main purpose of this article is using Finite Element Method to simulate the distributions of stress when model subject loadings and boundary conditions, then turn these into the intensities of lights to simulate the fringe patterns of transmission and scattered-light photoelasticity. And compare these results with the patterns of photoelasticity experiments. We use Finite Element Method to simulate the isoclinic and isochromatic patterns of photoelasicity experiments and the fringes while the secondary principle stress varies along the path of light and the secondary principle direction fixed.
In the simulation of transmission photoelasticity, we use the disk model to simulate Plane Polariscope and Circular Polariscope, then we can get a good result. And in the simulation of scattered-light photoelasticity fringe pattern, we also use the disk model to simulate the fringe pattern. Let the polarization and observation direction to be 45 degrees, then we can get the simulation fringe pattern which is close to the experiment pattern. So the result is good. Using the L shape model to simulate the fringes while the secondary principle stress varies along the path of light, the simulation fringe pattern compare with the experiment pattern, the result is found to be good.

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