From diffuse to localised damage through elastic interaction

Local damage processes that have been reported for ductile and brittle macroscopic behaviours are shown here to provide a possible link between these two contrasting behaviours. Using a local progressive damage law within a linear tensorial elastic interaction model, we reproduce experimentally observed macroscopic non-linear behaviours that continuously range from ductility with diffuse damage to brittleness with localised damage. The model exhibits power law distributions of damage events in space and size domains. The diffuse-localised and induced ductile-brittle transition appear to be controlled by the internal friction angle which influences the local interaction geometry.

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