STRAIN-BASED TRANSIENT-GRADIENT DAMAGE MODEL FOR FAILURE ANALYSES

A transient-gradient enhanced damage model has been developed for the numerical modelling of the damage and fracture process within a contin uum damage mechanics framework. Some deficiencies of existing gradient enhanced damage formulations for the simulation of macroscopic crack propagation are pointed out. The transient-gradient approach assumes a direct coupling between the material length parameter and the local s train state of the material, which leads to a transient behaviour of t he nonlocal effect. Details of the method are presented and fully elab orated in an incremental-iterative solution scheme. Mesh objectivity a nd physical relevance of the method are analysed by one-dimensional an d two-dimensional numerical examples. (C) 1998 Elsevier Science S.A. A ll rights reserved.