Effects of process zones on crack interactions

The problem of interaction among cracks, including the effects of process zones, is studied. The Dugdale-type cohesive-zone model is extended to mixed-modes of loading and is then used to evaluate the size of process zones. The interaction is considered by applying uniform normal and shear tractions on each crack surface caused by the remaining cracks. The magnitude of these interaction tractions relative to far-field stresses reflects the intensity of the interaction. The effect of process zones on the magnitude of interaction tractions is studied by comparing them with the corresponding elastic values. It is shown that process zones generally enhance the interaction, but effective properties are not altered significantly.