抄録
The shearing failure process of the powder bed in a direct shear tester has been represented in the Roscoe condition diagram (a three dimensional representation of the applied normal stress, shearing stress and void fraction) in conjunction with the data by tensile tests. The results show that this presentation permits to understand the effect of the void fraction on the shearing-failure process systematically and clearly. It is specially of interest that pattern of the shearing-failure process varied as a function of both the void fractions of initial and critical states corresponds well to the locus of the shearing process in the Roscoe diagram. The flow surface, the consolidation surface, the critical state line and the consolidation line for fine and coarse powders were clearly shown in the Roscoe diagram and the differences between them were interpreted qualitatively.
