Configurational Forces Derived from the Total Variation of the Rate of Global Dissipation

Artikel i vetenskaplig tidskrift, 2009

Based on the thermodynamic framework for combined configurational and deformational changes, recently discussed in [1], we consider dissipative material response and emphasize the fact that it is possible to identify explicit energetic changes due to configurational changes for “frozen” spatial configuration and, in addition, the configuration-induced material dissipation. The classical assumption (previously adopted in the literature) is to ignore the latter. In this paper, however, we define configurational forces by considering the total variation of the total dissipation with respect to configurational changes. The key task is then to compute the sensitivity of the internal variable rates to such configurational changes. We restrict to quasistatic loading under isothermal conditions and elastic-plastic response, and we apply the theory to the simplest possible case of an interface of dissimilar materials in a single bar.