引張・ねじり二軸応力下における損傷テンソルを用いた多孔質材料の損傷評価

抄録

A new method to evaluate damage state of the material containing spherical voids randomly was proposed by using the damage tensor and equivalent net stress in this paper. Tensile, torsional and tesile/tortional biaxial tests were performed the polymeric specimen containing expanded polystyrene which was regarded as three-dimensional ideal model. Then major axial strain was measured by performing image processing to a photograph of specimen, and these were compared with the equivalent net stress calculated based on voronoi tessellation. It was found that the fracture point of the specimen after tensile test was corresponding to the region of the highest equivalent net stress. In addition, major axial strain tended to increase in the region of the high net equivalent stress under conditions of monotonic loading with tension, torque and biavial, suggesting that damage state of porous materials was quantitatively estimated through the present method.