| Popis: |
The paper is concerned with the criterion which defines whether the plastic component J p of the deformation J integral for a non-growing crack can be expressed in terms of energy and complementary energy integrals using a two eta factor description. Earlier work, based on very general dimensional considerations, has shown that a two eta factor description, valid for all levels of deformation, is strictly accurate only for situations where the solid has a single length parameter. The present paper underpins this view, since it clearly shows, by an exact analysis of a specific model, that an exact two eta factor description is not possible when more than one length parameter is involved. |
