スポール破壊の損傷力学的解析におけるボイド発達の定式化

抄録

This paper is concerned with the elaborate modeling of ductile spall damage due to void nucleation and growth in viscoplastic materials by means of continuum damage mechanics. The evolution equation of a scalar damage variable is developed by taking account of nucleation and growth of spherical voids in a unit cell; it is expressed in terms of the rates of the void nucleation and its radius growth. The resulting damage evolution equation and elastic-viscoplastic constitutive equations of the damaged material are incorporated into the commercial hydrocode MANJUSRI-3D, and the axisymmetric two-dimensional analyses of the plate-impact tests are performed. The results of the numerical analyses are compared with those of the one-dimensional analyses, axisymmetric analysis without explicit modeling of void growth, and the corresponding experiments.