According to the strain energy density factor criterion under mixed - mode of i and ii , the distortional strain energy density factor criterion and dilatational strain energy density factor criterion are given . the twin shear stress criterion is applied to the v - notch problem under mixed - mode of i and ii
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By utilizing the above methods and the results of the finite element program named msc / nastran , the paper carries through specific calculations corresponding to the single stress singularity and the double stress singularity issues , which consist of the cracks for mode i , mode ii , the mixed mode crack of mode i and ii and many v - notched problems
