结合白光光弹和相移技术解包裹等差线的方法

UNWRAPPING ISOCHROMATIC BY COMBINING WHITE LIGHT PHOTOELASTICITY WITH PHASE SHIFTING THCHNOLOGY

根据条纹色彩的变化确定等差线级数,是一种普遍应用的白光光弹方法。另一种具有较高的精度、操作简便,被广泛应用的光弹技术是相移法。由于色彩特征变弱,白光光弹用于辨识三级以下的等差线条纹。相移法得到的等差线都是包裹的相位,并非等差级数,解包裹等差线也是一项复杂的工作。根据受力构件中应力是连续变化的性质,将白光光弹和相移技术相结合,得到一种解包裹全场等差线的新方法。所述的解包裹方法不依赖于零级条纹,不需要确定零级条纹。最后通过分析径向受压的圆盘,演示了解包裹的新方法。

Use of a color code to identify fringe orders has been in use in conventional photoelasticity. Phase shifting technology is the most widely used for isochromatic evaluation due to its simplicity and accuracy. The phase shifting method obtain isochromatic only in a wrapped form. On the one hand the colors tend to merge beyond fringe order three in white light photoelasticity,and on the other phase unwrapping is a challenging issue. Due to the fact that the isochromatic fringes are continuously varying in fringe patterns,the white light photoelasticity and the phase shifting technique are adapted to determine the isochromatic fringe orders. The advantage of new approach allows for determination of isochromatic fringe orders regardless whether the zero-order fringe is present or not. Experimental demonstration was performed on a disc under compressive loading.