Effects of Specimen Geometry on Stress Distribution in Sandwich Specimen Under Combined Loads

The effects of specimen geometry and loading conditions on the stress distribution in a sandwich specimen under combined loads are investigated by elastic finite element analysis. A commercial software NASTRAN is used in plain-strain two-dimensional finite element analysis of sandwich specimens; the analysis was performed for three different specimen shape factors and four different combined displacement conditions. The results of computational analysis suggest that the effect of the combined displacement angle, which is defined as the ratio of the shear displacement to the normal displacement, on the size of the non-homogeneous stress distribution is observed only in the case of the shear stress and von Mises stress. Also as the combined displacement angle increases, the size of the non-homogeneous stress distribution decreases in the case of the shear stress and increases in the case of the von Mises stress. In addition, as the specimen shape factor, which is defined as the ratio of the specimen length to the height, increases, the size of the non-homogeneous stress distribution under combined displacement conditions decreases significantly.