抄録
Spall damage analyses are conducted in the framework of continuum damage mechanics with special emphasis on the 3-dimensionality and the effect of void volume fraction on the spall process. The evolution equation of a scalar damage variable taking account of the nucleation and growth of spherical voids, and the elastic-viscoplastic constitutive equations extended to damaged materials are incorporated into the commercial hydrocode MANJUSRI-3D. The axisymmetric two-dimensional analyses of the plate-impact tests on OFHC copper plates are performed to examine the effect of the ratio of the target radius to its thickness and that of the volumetric strain related to the void development on the relation between volumetric strain and hydrostatic pressure.