Non‐local damage model with evolving internal length

Abstract

Abstract A modified non‐local damage model with evolving internal length, inspired from micromechanics, is developed. It is shown in particular that the non‐local influence between two points in the damaged material depends on the value of damage at each of these points. The resulting weight function is non‐symmetric and truncated. Finite element results and strain localization analysis on a one‐dimensional problem are presented and compared to those of the original non‐local damage model. It is shown that in the course of damage localization, the incremental strain profiles expand according to the modified non‐local model, instead of shrinking according to the original constitutive relation. Comparisons with experimental data on model materials with controlled porosity are also discussed. Acoustic emission analyses provide results with which the theoretical model is consistent qualitatively. This model also opens the path for durability mechanics analyses, where it has been demonstrated that the internal length in the non‐local model should evolve with environmentally induced damage. Copyright © 2004 John Wiley & Sons, Ltd.