复合型应力强度因子K_Ⅰ，K_Ⅱ的确定──全息光弹性资料预处理法

Determination of Mixed-Made Stress-Intensity Factors KI and KⅡ-Holo-photoelasticity Experimental Data Pre-processing Method

利用全息光弹性实验的等和线条纹图沿两径线方向上几个内环条纹上的数据点，通过回归分析拟合幂函数型回归曲线，并拓延使之逼近奇异性占优势的近场，从中推求数据点，据此计算了单边斜裂纹尖端应力强度因子ＫＩ、ＫⅡ．此法避免了近场采数的实际困难，旦只需要计算少数据点便可得到精度较高的结果。

he fitting curves of the power function are obtained by statistic regression analysis for the data of the inner layer fringe loops along the radial direction lines,and then the curves are extended approaching the near field of the crack tip to enter into the singularity dominant domain,using the data points extrapolated from the computed SIF(Stress intensity factors)KI and KII of the single edge oblique crack tip.In this procedure,the actual difficulty in data acquisition is avoided.Furthermore,the method can give accurate results with a small number of data points in the algorithms.